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we're here live in washington dc

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today we have not one but two scientific

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findings for you about oceans beyond

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earth we'll be going coast to coast and

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ocean to ocean to talk to experts

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starting from people right here in

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washington dc

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and then all also going all the way to

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the west coast to talk to nasa's jet

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propulsion laboratory in pasadena

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california

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and then we're going to go all the way

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to the east coast to talk to nasa's

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goddard space flight center in greenbelt

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maryland

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today's panelists are

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thomas zurbukin associate administrator

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for the science mission directorate

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jim greene director of planetary science

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mary wojtek lead scientist for nasa's

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astrobiology program

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the panelists at jpl in california are

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linda spilker

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cassini project scientist

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hunter waite cassini inms team lead with

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the southwest research institute or

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sweari in san antonio texas

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chris glenn cassini inms team associate

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also from sweary

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and joining us from goddard in maryland

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we have william sparks astronomer and

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lead author of the hubble findings with

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the space telescope science institute in

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baltimore

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the news today can be found at

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www.nasa.gov

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and also the following webpages

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if you'd like to ask a question via

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social media please use the hashtag ask

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nasa

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and with that thomas can you kick us off

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hey thanks so much felicia

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it's another great day of science at

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nasa here and in the science directorate

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we really focus on three objectives the

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first one is to understand and to

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improve life on earth

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we also do fundamental research from

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here to the depths of the universe and

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understand processes we've never

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understood before

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and the third topic is one that this is

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all about which is about a fundamental

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has failed the thinking of so many in

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the past and we can answer now hopefully

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in the near future and that is is there

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life elsewhere see here on earth there's

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a number of things that help life

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there's water in a liquid form we have

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an atmosphere we have a magnetic field

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that protects us from the hazards of

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space there's many things we have going

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for ourselves

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so the question where there's life out

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there

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relates to questions that we're making

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progress with all the time and questions

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that we have new questions that are

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coming forward we don't know yet whether

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there is life out there

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but

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right now we're making a lot of progress

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especially the outer solar system

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so this is exactly what today's stories

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are all about

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with this research

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we're making a big step forward towards

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answering the question

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is there life out there and with that

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i'm really turning it over to the team

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co-team

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thank you thomas so nasa's strategy for

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searching for life in the universe

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begins at home

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with an understanding of how life

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emerged and evolved here on earth and

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what the limits to life are on this

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planet we then project that out onto

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other places in our solar system to see

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if we can find habitable environments

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that could support life as we know it

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just 40 years ago

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nasa sent two viking landers to mars to

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look for evidence of life on the red

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planet at the same time oceanographers

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here on this planet on earth were

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exploring the last frontier the deep

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ocean

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and during that exploration they found

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an astonishing made an astonishing

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discovery that changed how we thought

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about earth and how we thought about

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life here on earth and that was an

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incredible oasis of life supported

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thousands of meters beneath the surface

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of the ocean far away from sunlight

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and it was supported by the energy

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produced by hydrothermal activity

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now this is actually this discovery was

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incredible for here on earth it led to

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but it pointed out a new type of biology

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supported by chemistry

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that didn't require sunlight which meant

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that we could extend our habitable

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as we imagine environments very much

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like our own hydrothermal vents here on

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earth could exist out there so today's

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discoveries

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have to do with ocean worlds beyond our

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own planet and jim's going to tell you

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about the missions that brought this to

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us

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you know it really began in the late

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1990s with the mission galileo

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galileo orbiting

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jupiter was flying by the individual

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moons the galilean moons and making

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observations of the atmosphere and many

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things in that solar system that mini

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solar system what it discovered from its

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magnetometers it flew real close

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to

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europa was a magnetic signature

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that's very familiar with our scientists

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because we interpreted as a current

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within an ocean underneath an ice shell

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in 2005

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cassini

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orbiting saturn flying by the moons of

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saturn

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with close flybys of enceladus it

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observed huge plumes of water emanating

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from cracks

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we now believe that enceladus also has a

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huge ocean

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we call these bodies and many others

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that are like them ocean worlds

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they are protected by an ice shell much

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like our atmosphere protects us our life

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here on earth and our ocean maintaining

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its liquid

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this is truly an exciting time for us to

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be able to probe those

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and really try to understand what's

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happening in these ocean worlds

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what we're going to talk about today are

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two really wonderful discoveries

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continuing back to cassini which has

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always been one of the major

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missions that we have making huge number

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of discoveries

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and we're going to talk about enceladus

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and what it's found out we're also going

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to talk about hubble observations

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back to europa

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these two ocean worlds were going to

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link together because they're so similar

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in many many ways that i hope you'll see

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as we go through our discoveries today

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so without further ado let's go to jpl

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and talk to linda spilker linda what's

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cassini been observing

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well thanks jim well cassini has been in

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orbit around saturn for almost 13 years

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and our unexpected discoveries about

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enceladus have been some of the most

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surprising

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today we're publishing a paper about our

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recent findings by cassini on enceladus

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we've detected hydrogen in the plume of

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enceladus that hydrogen is coming from a

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hydrothermal vent on the sea floor of

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enceladus going out into space through

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the plume

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and so this is a very significant

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finding because the hydrogen could be a

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potential source of chemical energy for

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any microbes that might be an enceladus

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ocean

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so this is a very exciting finding for

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the cassini tea

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now enceladus is too small to have

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retained the hydrogen when it formed and

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so the hydrogen we see today the

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hydrogen gas is coming from inside

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enceladus so let's take a quick look at

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some of cassini's past findings with

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this first image this is a view of the

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south pole of enceladus

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and the geysers or the jets are coming

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from those four cracks we nicknamed

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tiger stripes those bluish fractures

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that you can see at the south pole of

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enceladus in the next picture you can

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see that these jets are shooting out

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into space forming the giant plume

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around enceladus

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underneath that icy crust as jim said

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there's a global ocean that global ocean

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sits on top of a rocky core

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and some of cassini's findings pointed

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to hydrothermal vents

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basically hot water coming out after

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it's been mixed with the rocky core and

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this final image shows a thermal map the

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temperature of the south pole we can see

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the warmest temperatures with the yellow

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and red are right along the tiger stripe

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fractures

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so what's new today the new finding is

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finding hydrogen

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coming from the plume of enceladus and

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the fact that it could support

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potentially microbes with energy on the

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seafloor of enceladus now this finding

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is the result of 12 years of cassini

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investigations and it really represents

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a capstone finding for the mission

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because we now know that enceladus has

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almost all

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of the ingredients that you would need

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to support life as we know it on earth

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well here i have a model of the cassini

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spacecraft and hunter maybe you can show

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us where your instrument is that

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detected the hydrogen yes linda

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the ions instrument the ion neutral mass

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spectrometer is sitting on the fields

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and particle platform right here and it

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directly samples the gas that comes in

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as we fly through the plume

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as opposed to an ultraviolet

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spectrometer an infrared spectrometer

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which would look for scattered

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absorbed or emitted light coming from

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the molecules in a in a faraway lake

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location so this sampling is extremely

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important for detecting tray species and

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we were able to

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from previous flybys and previous

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measurements find out that the plume is

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98

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water

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it has

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traces of ammonia

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carbon dioxide and methane as well as

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some organics

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now the part that had been elusive to it

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before was the hydrogen

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and so let me

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back off here and pick up a

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similar model

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we have a simulation here of in the

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enceladus and the tiger stripes and so

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let me fly my spacecraft

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with the ims pointed in the direction of

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motion of the spacecraft through the

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plume material

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sampling the gas this is how it happened

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when we were making measurements it was

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about 8 kilometers above the surface and

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this happened in october of 2015.

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it's interesting to put this together

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with the other measures measurements

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we've made of the diff of the

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composition to try to draw some infra

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inferences about what's going on in the

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interior of the ocean because this

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material is telling us about composition

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of the ocean

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well hunter what was going through your

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head when you looked at the data and you

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00:11:30,389 --> 00:11:28,560
saw hydrogen

284
00:11:32,150 --> 00:11:30,399
well of course we were very excited

285
00:11:33,990 --> 00:11:32,160
because we've been planning this for

286
00:11:36,790 --> 00:11:34,000
quite a while and we've been thinking

287
00:11:39,590 --> 00:11:36,800
about what possible implications might

288
00:11:41,190 --> 00:11:39,600
be so for to discuss that let me turn

289
00:11:42,550 --> 00:11:41,200
over to chris and let him talk a little

290
00:11:44,790 --> 00:11:42,560
bit about that

291
00:11:47,030 --> 00:11:44,800
well linda our team considered numerous

292
00:11:49,269 --> 00:11:47,040
possibilities and after performing

293
00:11:51,110 --> 00:11:49,279
detailed geometrical analysis

294
00:11:52,550 --> 00:11:51,120
we found that the best explanation is

295
00:11:55,190 --> 00:11:52,560
that the hydrogen is produced by

296
00:11:57,590 --> 00:11:55,200
chemical reactions between warm water

297
00:12:00,790 --> 00:11:57,600
and rocks here's a graphic showing what

298
00:12:04,949 --> 00:12:02,870
we think that hydrothermal fluids are

299
00:12:06,150 --> 00:12:04,959
circulating below the ocean floor on

300
00:12:09,430 --> 00:12:06,160
enceladus

301
00:12:12,389 --> 00:12:09,440
this exposes rocks to warm water which

302
00:12:14,470 --> 00:12:12,399
drives geochemical transformations an

303
00:12:16,310 --> 00:12:14,480
important process that produces huge

304
00:12:18,069 --> 00:12:16,320
amounts of hydrogen is called

305
00:12:19,910 --> 00:12:18,079
serpentinization

306
00:12:22,470 --> 00:12:19,920
in this process certain minerals that

307
00:12:24,710 --> 00:12:22,480
are rich in iron react with water to

308
00:12:27,110 --> 00:12:24,720
form new minerals and hydrogen is

309
00:12:29,509 --> 00:12:27,120
produced

310
00:12:32,870 --> 00:12:29,519
this is important because it shows that

311
00:12:34,710 --> 00:12:32,880
the geochemistry acts on enceladus

312
00:12:36,949 --> 00:12:34,720
in addition to this we think that these

313
00:12:38,790 --> 00:12:36,959
warm hydrothermal fluids contain

314
00:12:41,269 --> 00:12:38,800
dissolved minerals and when these

315
00:12:44,629 --> 00:12:41,279
minerals mix with the ocean water which

316
00:12:46,150 --> 00:12:44,639
is cold mineral precipitates form at the

317
00:12:48,949 --> 00:12:46,160
sea floor

318
00:12:51,670 --> 00:12:48,959
these mineral precipitates on the earth

319
00:12:53,910 --> 00:12:51,680
form white solids so we call them white

320
00:12:55,990 --> 00:12:53,920
smokers

321
00:12:58,069 --> 00:12:56,000
here's a video showing an example of one

322
00:13:00,629 --> 00:12:58,079
of these systems on enceladus

323
00:13:02,629 --> 00:13:00,639
i mean on the earth we don't know if the

324
00:13:04,870 --> 00:13:02,639
systems on enceladus look like this but

325
00:13:07,670 --> 00:13:04,880
this is an example from the earth

326
00:13:09,990 --> 00:13:07,680
these vents on the earth support teeming

327
00:13:12,949 --> 00:13:10,000
communities of organisms anchored by

328
00:13:15,430 --> 00:13:12,959
microbes that feed on chemical energy

329
00:13:17,910 --> 00:13:15,440
rather than sunlight an important

330
00:13:20,470 --> 00:13:17,920
reaction at the base of the food chain

331
00:13:22,949 --> 00:13:20,480
is called methanogenesis this is where

332
00:13:25,509 --> 00:13:22,959
microbes combine hydrogen with carbon

333
00:13:27,829 --> 00:13:25,519
dioxide to make methane and they get a

334
00:13:30,150 --> 00:13:27,839
jolt of energy out of the process

335
00:13:32,949 --> 00:13:30,160
they use this energy to synthesize some

336
00:13:34,790 --> 00:13:32,959
of their complex biomolecules such as

337
00:13:36,550 --> 00:13:34,800
sugar molecules

338
00:13:39,190 --> 00:13:36,560
what is intriguing about the data at

339
00:13:41,190 --> 00:13:39,200
enceladus with the hydrogen detection

340
00:13:43,430 --> 00:13:41,200
is that we are now able to determine how

341
00:13:46,870 --> 00:13:43,440
much energy would be available from the

342
00:13:49,509 --> 00:13:46,880
methanogenesis reaction at enceladus

343
00:13:51,030 --> 00:13:49,519
we have made the first calorie count in

344
00:13:53,190 --> 00:13:51,040
an alien ocean

345
00:13:55,829 --> 00:13:53,200
this is a key step towards understanding

346
00:13:57,269 --> 00:13:55,839
the habitability of enceladus

347
00:13:59,990 --> 00:13:57,279
well chris do you think there could be

348
00:14:01,910 --> 00:14:00,000
microbes or even shrimp in the ocean on

349
00:14:04,550 --> 00:14:01,920
enceladus why that would be wonderful

350
00:14:06,949 --> 00:14:04,560
linda but we haven't discovered evidence

351
00:14:07,750 --> 00:14:06,959
of organisms on enceladus

352
00:14:10,069 --> 00:14:07,760
but

353
00:14:13,030 --> 00:14:10,079
i'm encouraged by the geochemical data

354
00:14:14,790 --> 00:14:13,040
which could allow for this possibility

355
00:14:17,509 --> 00:14:14,800
well thank you very much hunter thank

356
00:14:20,629 --> 00:14:17,519
you chris well when cassini was first

357
00:14:23,110 --> 00:14:20,639
built we never thought we would see an

358
00:14:24,230 --> 00:14:23,120
active ocean world like enceladus at

359
00:14:26,949 --> 00:14:24,240
saturn

360
00:14:29,509 --> 00:14:26,959
so cassini can look for habitability but

361
00:14:32,230 --> 00:14:29,519
we don't have the instruments to look

362
00:14:34,550 --> 00:14:32,240
for life we've come as far as we can go

363
00:14:37,110 --> 00:14:34,560
so it remains for a future mission to

364
00:14:39,030 --> 00:14:37,120
detect life at enceladus

365
00:14:41,509 --> 00:14:39,040
and the cassini team is so excited about

366
00:14:44,949 --> 00:14:41,519
these new findings and so mary why don't

367
00:14:46,230 --> 00:14:44,959
you put this in a broader context for us

368
00:14:48,150 --> 00:14:46,240
thank you linda

369
00:14:50,710 --> 00:14:48,160
well first of all chris i recognize that

370
00:14:53,189 --> 00:14:50,720
footage from one of the nasa researchers

371
00:14:54,790 --> 00:14:53,199
chris german uh exploring the east

372
00:14:56,829 --> 00:14:54,800
pacific rise which was actually a

373
00:15:00,310 --> 00:14:56,839
hydrothermal system very close to the

374
00:15:03,590 --> 00:15:00,320
original uh observation 40 years ago at

375
00:15:06,230 --> 00:15:03,600
the galapagos rift

376
00:15:07,829 --> 00:15:06,240
so while we don't understand what the

377
00:15:09,990 --> 00:15:07,839
structures would be and there may be no

378
00:15:12,310 --> 00:15:10,000
way for us to tell remotely until we

379
00:15:13,990 --> 00:15:12,320
actually get into these oceans certainly

380
00:15:15,829 --> 00:15:14,000
this finding suggests that there's a

381
00:15:18,470 --> 00:15:15,839
significant amount of hydrothermal

382
00:15:19,990 --> 00:15:18,480
activity to produce such a strong signal

383
00:15:23,189 --> 00:15:20,000
of hydrogen

384
00:15:26,230 --> 00:15:23,199
and this hydrogen is a good source of

385
00:15:27,829 --> 00:15:26,240
chemical energy to support life now what

386
00:15:29,670 --> 00:15:27,839
else have we been thinking about that

387
00:15:32,069 --> 00:15:29,680
life needs so i have a figure here to go

388
00:15:35,189 --> 00:15:32,079
over sort of the triad of what we need

389
00:15:37,350 --> 00:15:35,199
for life so can i have the figure please

390
00:15:39,430 --> 00:15:37,360
so of course you know that we need water

391
00:15:40,710 --> 00:15:39,440
and here we are at ocean worlds so we

392
00:15:43,189 --> 00:15:40,720
have the water

393
00:15:45,670 --> 00:15:43,199
we need chemical elements that can make

394
00:15:47,430 --> 00:15:45,680
the building blocks that go into making

395
00:15:49,829 --> 00:15:47,440
cells and provide

396
00:15:52,550 --> 00:15:49,839
molecules for metabolism we need carbon

397
00:15:54,230 --> 00:15:52,560
hydrogen nitrogen oxygen phosphorus and

398
00:15:56,790 --> 00:15:54,240
sulfur which are down in the lower left

399
00:15:59,269 --> 00:15:56,800
of the triangle and here we get to check

400
00:16:01,990 --> 00:15:59,279
off another box we have found energy to

401
00:16:04,310 --> 00:16:02,000
support life hydrogen gas provides that

402
00:16:06,629 --> 00:16:04,320
energy now all we need is to see if

403
00:16:08,470 --> 00:16:06,639
enceladus had enough time or any of the

404
00:16:11,910 --> 00:16:08,480
other systems in the saturn in her

405
00:16:13,910 --> 00:16:11,920
jovian world had enough time to evolve

406
00:16:16,470 --> 00:16:13,920
life and have life

407
00:16:18,710 --> 00:16:16,480
make its imprint on its ocean

408
00:16:20,389 --> 00:16:18,720
so now we have a another observation

409
00:16:22,550 --> 00:16:20,399
that kind of connects the world and is

410
00:16:24,629 --> 00:16:22,560
related to what we just heard about and

411
00:16:26,870 --> 00:16:24,639
jim's going to tell you about this

412
00:16:29,030 --> 00:16:26,880
so indeed the next discovery we want to

413
00:16:31,030 --> 00:16:29,040
talk about which is also coming out this

414
00:16:33,509 --> 00:16:31,040
week in our science journals

415
00:16:35,990 --> 00:16:33,519
is from the hubble space telescope that

416
00:16:38,310 --> 00:16:36,000
famous telescope that just keeps on

417
00:16:39,990 --> 00:16:38,320
making wonderful observations has

418
00:16:42,550 --> 00:16:40,000
actually been observing

419
00:16:44,470 --> 00:16:42,560
europa for many years

420
00:16:47,430 --> 00:16:44,480
so let's go to goddard space flight

421
00:16:49,509 --> 00:16:47,440
center and talk to william sparks bill

422
00:16:53,670 --> 00:16:49,519
give us a little background on what we

423
00:16:59,189 --> 00:16:56,389
europa is one of the four major moons of

424
00:17:01,829 --> 00:16:59,199
jupiter it's about the same size as our

425
00:17:04,949 --> 00:17:01,839
own moon but it looks very different

426
00:17:07,110 --> 00:17:04,959
it's got a smooth bright white surface

427
00:17:08,710 --> 00:17:07,120
covered in these dark cracks and red

428
00:17:10,789 --> 00:17:08,720
patches

429
00:17:13,189 --> 00:17:10,799
the reason for that and what makes

430
00:17:15,429 --> 00:17:13,199
europas incredibly interesting

431
00:17:18,630 --> 00:17:15,439
is that it's thought to be engulfed by a

432
00:17:20,630 --> 00:17:18,640
global ocean under a thick crust of ice

433
00:17:22,390 --> 00:17:20,640
in fact it's got twice as much ocean as

434
00:17:25,350 --> 00:17:22,400
planet earth

435
00:17:27,110 --> 00:17:25,360
if we have a salty ocean in contact with

436
00:17:29,510 --> 00:17:27,120
a rocky core

437
00:17:31,590 --> 00:17:29,520
and energy from a variety of sources as

438
00:17:33,750 --> 00:17:31,600
we just heard from mary we have many of

439
00:17:38,630 --> 00:17:33,760
the ingredients thought to be necessary

440
00:17:42,549 --> 00:17:40,230
your observations from hubble what are

441
00:17:46,549 --> 00:17:42,559
you now seeing that's important to our

442
00:17:49,590 --> 00:17:46,559
understanding of habitability on europa

443
00:17:52,070 --> 00:17:49,600
in 2014 we used the hubble and

444
00:17:54,390 --> 00:17:52,080
detected evidence of what are probably

445
00:17:56,710 --> 00:17:54,400
water vapor plumes emerging from the

446
00:17:59,190 --> 00:17:56,720
surface of europa that's important

447
00:18:01,270 --> 00:17:59,200
because it could be giving us access to

448
00:18:03,270 --> 00:18:01,280
surface liquid water without having to

449
00:18:05,110 --> 00:18:03,280
drill through miles of ice

450
00:18:06,710 --> 00:18:05,120
in 2016

451
00:18:07,909 --> 00:18:06,720
the new observations that we're just

452
00:18:10,230 --> 00:18:07,919
publishing

453
00:18:12,549 --> 00:18:10,240
we saw a similar candidate almost

454
00:18:15,669 --> 00:18:12,559
identical in appearance and at the

455
00:18:18,630 --> 00:18:15,679
identical location to one of the 20 40

456
00:18:20,710 --> 00:18:18,640
candidates it's very important uh in an

457
00:18:22,710 --> 00:18:20,720
intermittent phenomenon to establish

458
00:18:25,270 --> 00:18:22,720
repeatability it gives us a lot more

459
00:18:27,029 --> 00:18:25,280
faith in the observation

460
00:18:29,029 --> 00:18:27,039
the other thing it allows us to do given

461
00:18:31,430 --> 00:18:29,039
the position of europa uh given the

462
00:18:32,549 --> 00:18:31,440
position of the candidate on europa uh

463
00:18:34,710 --> 00:18:32,559
is to look

464
00:18:36,789 --> 00:18:34,720
with more fidelity at that position and

465
00:18:39,510 --> 00:18:36,799
see what else we can find there if we

466
00:18:41,270 --> 00:18:39,520
just look at the map of europa uh we

467
00:18:43,909 --> 00:18:41,280
don't see anything particularly

468
00:18:45,830 --> 00:18:43,919
remarkable the exact location of the

469
00:18:47,029 --> 00:18:45,840
plume candidate shown by the green

470
00:18:49,830 --> 00:18:47,039
ellipse

471
00:18:52,630 --> 00:18:49,840
but if we look back to the galileo data

472
00:18:54,150 --> 00:18:52,640
galileo in the 1990s published a thermal

473
00:18:57,190 --> 00:18:54,160
image and

474
00:18:59,750 --> 00:18:57,200
right at the peak of the thermal image

475
00:19:02,470 --> 00:18:59,760
that's where the plume candidate is

476
00:19:05,190 --> 00:19:02,480
this uh hot spot on the surface of

477
00:19:06,950 --> 00:19:05,200
europa on the europa night side was

478
00:19:09,909 --> 00:19:06,960
identified at the time as a thermal

479
00:19:13,270 --> 00:19:09,919
anomaly and it's sitting right on top of

480
00:19:16,390 --> 00:19:13,280
the position of our plume candidate

481
00:19:18,870 --> 00:19:16,400
bill wow that's fantastic

482
00:19:21,669 --> 00:19:18,880
you know we didn't know when galileo was

483
00:19:24,630 --> 00:19:21,679
flying by europa how the ocean could

484
00:19:27,510 --> 00:19:24,640
possibly communicate with the surface

485
00:19:29,750 --> 00:19:27,520
and now these plumes that hubble may be

486
00:19:32,549 --> 00:19:29,760
observing is giving us that tantalizing

487
00:19:35,029 --> 00:19:32,559
glimpse something exactly what we see on

488
00:19:38,230 --> 00:19:35,039
enceladus may be going on can you tell

489
00:19:40,230 --> 00:19:38,240
us a little more about how these plumes

490
00:19:42,390 --> 00:19:40,240
and that hot spot might relate to each

491
00:19:44,470 --> 00:19:42,400
other

492
00:19:46,470 --> 00:19:44,480
uh yes jim it's it's it's really

493
00:19:48,789 --> 00:19:46,480
intriguing it was quite astonishing in

494
00:19:50,470 --> 00:19:48,799
fact just to see the coincidence of the

495
00:19:51,430 --> 00:19:50,480
two

496
00:19:53,029 --> 00:19:51,440
but

497
00:19:55,270 --> 00:19:53,039
it wasn't an accident that we looked for

498
00:19:58,070 --> 00:19:55,280
the thermal imaging uh we did it by

499
00:19:59,669 --> 00:19:58,080
analogy within itself as as we all know

500
00:20:01,750 --> 00:19:59,679
as you know and the other people here

501
00:20:03,590 --> 00:20:01,760
know uh the plumes of enceladus are

502
00:20:05,669 --> 00:20:03,600
associated with a heat source and it's

503
00:20:07,350 --> 00:20:05,679
very distinctive signature and so we

504
00:20:09,909 --> 00:20:07,360
looked to see if we could find thermal

505
00:20:12,630 --> 00:20:09,919
imaging of the surface of europa and we

506
00:20:14,310 --> 00:20:12,640
did and the peak hottest point in the

507
00:20:16,390 --> 00:20:14,320
europa night side was right where our

508
00:20:18,789 --> 00:20:16,400
plume candidate is there's two like

509
00:20:21,110 --> 00:20:18,799
there's two possible explanations for a

510
00:20:23,110 --> 00:20:21,120
causal connection obviously coincidences

511
00:20:24,789 --> 00:20:23,120
could just occur but there are reasons

512
00:20:25,990 --> 00:20:24,799
to think there could be a causal

513
00:20:28,070 --> 00:20:26,000
relationship

514
00:20:29,990 --> 00:20:28,080
one possibility is if

515
00:20:31,110 --> 00:20:30,000
there's liquid water at the depth below

516
00:20:33,430 --> 00:20:31,120
the ice

517
00:20:34,950 --> 00:20:33,440
surface and the liquid water is

518
00:20:37,190 --> 00:20:34,960
obviously warmer than the surface the

519
00:20:39,029 --> 00:20:37,200
heat can flow up through the ice and

520
00:20:41,270 --> 00:20:39,039
cause a thermal anomaly and cracks in

521
00:20:44,230 --> 00:20:41,280
the ice could give us the plumes

522
00:20:45,909 --> 00:20:44,240
conversely the plumes themselves could

523
00:20:48,390 --> 00:20:45,919
simply be venting

524
00:20:50,630 --> 00:20:48,400
water vapor high into space

525
00:20:53,909 --> 00:20:50,640
from the europa surface we see plumes

526
00:20:55,750 --> 00:20:53,919
rising to a 100 kilometers 60 miles

527
00:20:58,630 --> 00:20:55,760
and we would expect the water vapor to

528
00:20:59,750 --> 00:20:58,640
spread out over a much bigger area than

529
00:21:01,510 --> 00:20:59,760
that

530
00:21:03,990 --> 00:21:01,520
we're not at escape velocity so it's got

531
00:21:05,990 --> 00:21:04,000
to come back down if a fine mist of

532
00:21:08,310 --> 00:21:06,000
water vapor rains back down onto the

533
00:21:10,390 --> 00:21:08,320
surface then it can change the thermal

534
00:21:13,190 --> 00:21:10,400
character of that surface and allow it

535
00:21:14,789 --> 00:21:13,200
to retain heat longer and so instead of

536
00:21:19,029 --> 00:21:14,799
heat coming up from below it could be

537
00:21:21,430 --> 00:21:19,039
heat from above being slowly re-radiated

538
00:21:23,110 --> 00:21:21,440
during the europa night time

539
00:21:25,669 --> 00:21:23,120
and so it's a very intriguing pair of

540
00:21:27,270 --> 00:21:25,679
results we discovered a repeating plume

541
00:21:29,190 --> 00:21:27,280
candidate and when we looked at the

542
00:21:31,430 --> 00:21:29,200
galileo data we found the position of

543
00:21:33,029 --> 00:21:31,440
that repeating plume candidate that was

544
00:21:35,510 --> 00:21:33,039
right at the position of a thermal

545
00:21:37,430 --> 00:21:35,520
anomaly we look forward to the europa

546
00:21:38,950 --> 00:21:37,440
clipper mission which jim is going to

547
00:21:40,950 --> 00:21:38,960
tell us about and

548
00:21:44,230 --> 00:21:40,960
that will characterize this and other

549
00:21:46,230 --> 00:21:44,240
areas in great detail

550
00:21:48,789 --> 00:21:46,240
you know the cassini observations that

551
00:21:51,110 --> 00:21:48,799
enceladus and the hubble observations at

552
00:21:53,750 --> 00:21:51,120
europa tells you you we're using

553
00:21:56,310 --> 00:21:53,760
everything in our arsenal to probe these

554
00:21:59,510 --> 00:21:56,320
new ocean worlds that we've discovered

555
00:22:03,029 --> 00:21:59,520
this is truly a really exciting time

556
00:22:05,190 --> 00:22:03,039
cassini unfortunately is near its end uh

557
00:22:07,430 --> 00:22:05,200
it will be uh plunged into the

558
00:22:10,310 --> 00:22:07,440
atmosphere of saturn it's running out of

559
00:22:12,950 --> 00:22:10,320
fuel on the 15th of september and so

560
00:22:15,430 --> 00:22:12,960
these indeed are the last discoveries

561
00:22:17,990 --> 00:22:15,440
that we're talking about from cassini as

562
00:22:19,830 --> 00:22:18,000
it relates to enceladus

563
00:22:22,549 --> 00:22:19,840
the next big mission that we're working

564
00:22:25,750 --> 00:22:22,559
on is called the europa clipper and this

565
00:22:28,390 --> 00:22:25,760
particular mission is going to enceladus

566
00:22:30,630 --> 00:22:28,400
it has nine major instruments on it and

567
00:22:34,549 --> 00:22:30,640
these discoveries are coming at just the

568
00:22:37,430 --> 00:22:34,559
perfect time it enables us to make the

569
00:22:40,710 --> 00:22:37,440
right set of observations that can tell

570
00:22:42,630 --> 00:22:40,720
us much more about these ocean worlds

571
00:22:44,230 --> 00:22:42,640
europa in particular

572
00:22:45,750 --> 00:22:44,240
can i have my

573
00:22:48,070 --> 00:22:45,760
video please

574
00:22:52,950 --> 00:22:48,080
the europa clipper will orbit jupiter

575
00:22:55,830 --> 00:22:52,960
but it makes very close flybys of europa

576
00:22:57,669 --> 00:22:55,840
it has instruments like the magnetometer

577
00:22:59,029 --> 00:22:57,679
once again that will make measurements

578
00:23:02,470 --> 00:22:59,039
of its ocean

579
00:23:05,270 --> 00:23:02,480
it also has an ice penetrating radar

580
00:23:08,789 --> 00:23:05,280
this radar will tell us how thick or

581
00:23:11,909 --> 00:23:08,799
thin these ice shelves are and how close

582
00:23:14,070 --> 00:23:11,919
then the ocean might be to cracks

583
00:23:15,029 --> 00:23:14,080
the next major instrument that it has is

584
00:23:17,430 --> 00:23:15,039
thermal

585
00:23:20,870 --> 00:23:17,440
imaging going back to what we learned

586
00:23:23,750 --> 00:23:20,880
from enceladus how hot are these areas

587
00:23:26,470 --> 00:23:23,760
are there cracks there like we see now

588
00:23:29,750 --> 00:23:26,480
with the plumes from uh the hubble

589
00:23:32,710 --> 00:23:29,760
observations and the hot spots still

590
00:23:35,590 --> 00:23:32,720
being hot from galileo observations more

591
00:23:38,789 --> 00:23:35,600
than 15 or so years ago

592
00:23:41,110 --> 00:23:38,799
in addition to that we have a uv

593
00:23:44,070 --> 00:23:41,120
spectrometer this imager is going to be

594
00:23:45,990 --> 00:23:44,080
the plume finder so as we go back and

595
00:23:47,909 --> 00:23:46,000
orbit out away from jupiter we're going

596
00:23:50,070 --> 00:23:47,919
to look back at enceladus we're going to

597
00:23:52,789 --> 00:23:50,080
be looking for those plumes and then

598
00:23:54,950 --> 00:23:52,799
diving back in and hopefully if

599
00:23:58,470 --> 00:23:54,960
everything works right flying through

600
00:24:01,190 --> 00:23:58,480
the plumes much like cassini has done

601
00:24:03,750 --> 00:24:01,200
at enceladus but now we'll have the

602
00:24:06,070 --> 00:24:03,760
right set of observations to make on

603
00:24:07,750 --> 00:24:06,080
that spacecraft the europa clipper will

604
00:24:10,870 --> 00:24:07,760
have an advanced

605
00:24:13,269 --> 00:24:10,880
mass spectrometer actually hunter weight

606
00:24:15,830 --> 00:24:13,279
is our principal scientist or principal

607
00:24:18,390 --> 00:24:15,840
investigator for that instrument

608
00:24:21,110 --> 00:24:18,400
so what a fantastic time

609
00:24:22,549 --> 00:24:21,120
coming up these observations are really

610
00:24:25,029 --> 00:24:22,559
informing us

611
00:24:26,870 --> 00:24:25,039
of major things happening in these ocean

612
00:24:29,510 --> 00:24:26,880
worlds right now

613
00:24:32,310 --> 00:24:29,520
what i really want you to walk away with

614
00:24:34,870 --> 00:24:32,320
is we're pushing the frontiers we're

615
00:24:37,510 --> 00:24:34,880
finding new environments

616
00:24:39,750 --> 00:24:37,520
we're looking in a way that we've never

617
00:24:43,269 --> 00:24:39,760
thought possible before

618
00:24:45,269 --> 00:24:43,279
for environments in our solar system

619
00:24:46,470 --> 00:24:45,279
which may harbor life

620
00:24:49,909 --> 00:24:46,480
today

621
00:24:51,830 --> 00:24:49,919
with that let me give it back to felicia

622
00:24:54,149 --> 00:24:51,840
thanks jim now we're going to go into

623
00:24:56,230 --> 00:24:54,159
our q a session for those joining us

624
00:24:58,710 --> 00:24:56,240
online please submit a question using

625
00:24:59,990 --> 00:24:58,720
the hashtag asknasa

626
00:25:01,510 --> 00:25:00,000
for those in the room if you'd like to

627
00:25:03,430 --> 00:25:01,520
ask a question please raise your hand

628
00:25:04,789 --> 00:25:03,440
and a mic will be passed to you and if

629
00:25:06,390 --> 00:25:04,799
you're pressed please state your name

630
00:25:08,149 --> 00:25:06,400
and affiliation

631
00:25:11,909 --> 00:25:08,159
so let's start with questions from the

632
00:25:15,190 --> 00:25:13,590
okay well before we go to questions from

633
00:25:17,590 --> 00:25:15,200
the room let's go ahead to the phone

634
00:25:21,590 --> 00:25:17,600
lines first we have camille carlisle

635
00:25:24,390 --> 00:25:21,600
from the sky and telescope magazine

636
00:25:25,430 --> 00:25:24,400
hi can you hear me yes

637
00:25:27,269 --> 00:25:25,440
okay

638
00:25:29,830 --> 00:25:27,279
thanks to my call

639
00:25:31,990 --> 00:25:29,840
two questions one you mentioned that we

640
00:25:33,190 --> 00:25:32,000
essentially have a calorie count now

641
00:25:35,350 --> 00:25:33,200
with the tire

642
00:25:38,070 --> 00:25:35,360
just how much energy is available can

643
00:25:40,390 --> 00:25:38,080
you put some sort of detail on that

644
00:25:42,230 --> 00:25:40,400
and this is a logistics question maybe i

645
00:25:44,390 --> 00:25:42,240
missed it is there a website for all the

646
00:25:45,830 --> 00:25:44,400
press images that we can go to and and

647
00:25:47,750 --> 00:25:45,840
get them

648
00:25:49,990 --> 00:25:47,760
so felicia can you tell us the press

649
00:25:51,510 --> 00:25:50,000
site and we'll go to jpl to get the

650
00:25:53,269 --> 00:25:51,520
calorie count

651
00:25:54,789 --> 00:25:53,279
so if you want more information about

652
00:25:56,510 --> 00:25:54,799
everything we've talked about today

653
00:25:58,870 --> 00:25:56,520
definitely go to

654
00:26:00,470 --> 00:25:58,880
www.nasa.gov our press release will be

655
00:26:02,149 --> 00:26:00,480
on that page and that will link to

656
00:26:03,990 --> 00:26:02,159
additional materials

657
00:26:05,830 --> 00:26:04,000
i believe by going to the jpl saturn

658
00:26:07,510 --> 00:26:05,840
page also there's materials so please

659
00:26:09,350 --> 00:26:07,520
just go to the two pages that were just

660
00:26:11,269 --> 00:26:09,360
on the screen earlier and you should be

661
00:26:12,630 --> 00:26:11,279
able to get the materials you need and i

662
00:26:18,870 --> 00:26:12,640
guess uh for the second part of the

663
00:26:23,190 --> 00:26:20,630
that's an excellent question the plume

664
00:26:26,310 --> 00:26:23,200
gas mixture from the hydrogen number we

665
00:26:37,990 --> 00:26:26,320
derived is equivalent to roughly 300

666
00:26:46,149 --> 00:26:39,909
next uh we have on the phone lines we

667
00:26:50,470 --> 00:26:48,470
hi thanks very much for having this call

668
00:26:52,390 --> 00:26:50,480
i was questioned about the plume

669
00:26:54,870 --> 00:26:52,400
evidence europa

670
00:26:57,110 --> 00:26:54,880
you said you found it in 2014 in 2016

671
00:26:58,789 --> 00:26:57,120
this evidence of water plumes

672
00:27:00,230 --> 00:26:58,799
how many times did you look

673
00:27:01,909 --> 00:27:00,240
and was it not there and i guess what

674
00:27:04,950 --> 00:27:01,919
i'm trying to get at is there any sense

675
00:27:07,269 --> 00:27:04,960
of how intermittent this plume might be

676
00:27:09,669 --> 00:27:07,279
if it does indeed exist

677
00:27:12,630 --> 00:27:09,679
of course bill now has been on the uh a

678
00:27:17,269 --> 00:27:12,640
number of major observations from hubble

679
00:27:22,230 --> 00:27:18,470
uh yes

680
00:27:24,950 --> 00:27:22,240
we look 12 times and we saw it twice in

681
00:27:27,590 --> 00:27:24,960
that location we did see

682
00:27:30,950 --> 00:27:27,600
some evidence of plumes around the south

683
00:27:32,870 --> 00:27:30,960
pole polar regions a couple of times too

684
00:27:35,110 --> 00:27:32,880
but it's much harder to

685
00:27:37,269 --> 00:27:35,120
locate

686
00:27:40,149 --> 00:27:37,279
the source when you're down at the polar

687
00:27:42,310 --> 00:27:40,159
region and there isn't any uh coverage

688
00:27:45,190 --> 00:27:42,320
by galileo in that region either so we

689
00:27:48,070 --> 00:27:45,200
were we were lucky to find this one that

690
00:27:50,630 --> 00:27:48,080
did repeat was actually near the equator

691
00:27:53,430 --> 00:27:50,640
and so it was twice out of 12 times one

692
00:27:56,310 --> 00:27:54,789
would you care to characterize how

693
00:27:58,230 --> 00:27:56,320
confident you are these are actually

694
00:27:59,750 --> 00:27:58,240
plumes

695
00:28:01,029 --> 00:27:59,760
yeah

696
00:28:11,990 --> 00:28:01,039
uh

697
00:28:14,549 --> 00:28:12,000
four sigma results now that's

698
00:28:15,750 --> 00:28:14,559
not quite as uh

699
00:28:18,230 --> 00:28:15,760
strong

700
00:28:19,510 --> 00:28:18,240
evidences you'd really like you'd prefer

701
00:28:21,510 --> 00:28:19,520
it to be

702
00:28:23,110 --> 00:28:21,520
stronger than that because at that level

703
00:28:25,110 --> 00:28:23,120
there's always the possibility that

704
00:28:26,950 --> 00:28:25,120
there's some sort of instrumental effect

705
00:28:31,029 --> 00:28:26,960
that you don't know about

706
00:28:32,470 --> 00:28:31,039
we've covered our cells in terms of

707
00:28:34,470 --> 00:28:32,480
trying to

708
00:28:37,909 --> 00:28:34,480
understand what possible instrumental

709
00:28:39,750 --> 00:28:37,919
effects could have caused this

710
00:28:40,470 --> 00:28:39,760
and every single one that we can think

711
00:28:44,389 --> 00:28:40,480
of

712
00:28:46,230 --> 00:28:44,399
it so for example

713
00:28:48,950 --> 00:28:46,240
the two observations that i showed

714
00:28:51,750 --> 00:28:48,960
although they look the same in the same

715
00:28:54,070 --> 00:28:51,760
position when we project them on the sky

716
00:28:55,830 --> 00:28:54,080
when they were taken with the camera the

717
00:28:58,710 --> 00:28:55,840
hubble was in a completely different

718
00:29:00,630 --> 00:28:58,720
orientation for those two images and so

719
00:29:03,029 --> 00:29:00,640
they're in completely different parts of

720
00:29:05,029 --> 00:29:03,039
the camera uh with the telescope rolled

721
00:29:08,630 --> 00:29:05,039
around at a completely different angle

722
00:29:10,789 --> 00:29:08,640
and that eliminates a a whole bunch of

723
00:29:16,070 --> 00:29:10,799
potential systematics that could cause

724
00:29:17,190 --> 00:29:16,080
it so from the hubble uh perspective um

725
00:29:18,710 --> 00:29:17,200
we're

726
00:29:20,789 --> 00:29:18,720
i wouldn't say it's not completely

727
00:29:22,389 --> 00:29:20,799
unequivocal the way it is with enceladus

728
00:29:23,430 --> 00:29:22,399
we're still at the limits of what hubble

729
00:29:25,750 --> 00:29:23,440
can do

730
00:29:28,310 --> 00:29:25,760
but we're growing in confidence because

731
00:29:30,310 --> 00:29:28,320
of the repeat and because of in my case

732
00:29:31,430 --> 00:29:30,320
at least with i i find the correlation

733
00:29:33,750 --> 00:29:31,440
with the

734
00:29:36,470 --> 00:29:33,760
galileo thermal data quite quite quite

735
00:29:38,549 --> 00:29:36,480
intriguing and quite compelling

736
00:29:41,990 --> 00:29:38,559
you know from my perspective

737
00:29:44,310 --> 00:29:42,000
uh as as bill mentioned these plumes are

738
00:29:47,909 --> 00:29:44,320
up to 50 kilometers and perhaps as high

739
00:29:51,190 --> 00:29:47,919
as a 100 kilometers europa is the size

740
00:29:52,950 --> 00:29:51,200
of our own moon it's an enormous body

741
00:29:55,510 --> 00:29:52,960
and therefore there must be enormous

742
00:29:57,430 --> 00:29:55,520
energy to be able to loft these

743
00:30:00,070 --> 00:29:57,440
potential water

744
00:30:01,190 --> 00:30:00,080
jets high enough for us to be able to

745
00:30:04,149 --> 00:30:01,200
observe it

746
00:30:06,549 --> 00:30:04,159
five astronomical units away it's really

747
00:30:08,950 --> 00:30:06,559
a remarkable set of observations

748
00:30:11,190 --> 00:30:08,960
unfortunately you know it's not as

749
00:30:14,710 --> 00:30:11,200
periodic as the enceladus plumes which

750
00:30:17,830 --> 00:30:14,720
are on all the time and so uh

751
00:30:19,990 --> 00:30:17,840
going back to europa as bill has uh and

752
00:30:22,070 --> 00:30:20,000
his team and looked at it periodically

753
00:30:23,909 --> 00:30:22,080
is really giving us the confidence that

754
00:30:26,470 --> 00:30:23,919
they're there they may not be as

755
00:30:29,190 --> 00:30:26,480
periodic but indeed now it looks like

756
00:30:30,470 --> 00:30:29,200
the water the ocean is communicating

757
00:30:32,710 --> 00:30:30,480
with the surface

758
00:30:35,350 --> 00:30:32,720
bill and his team is also talking about

759
00:30:37,830 --> 00:30:35,360
how they can make more observations

760
00:30:41,669 --> 00:30:37,840
between now and when we do indeed launch

761
00:30:44,070 --> 00:30:41,679
the europa clipper in the 2020s

762
00:30:45,830 --> 00:30:44,080
let's go to the phones

763
00:30:47,750 --> 00:30:45,840
okay well before we go to the phones

764
00:30:50,230 --> 00:30:47,760
let's go ahead to social media where

765
00:30:51,110 --> 00:30:50,240
emily is helping field the questions so

766
00:30:52,950 --> 00:30:51,120
emily

767
00:30:54,789 --> 00:30:52,960
sure we have a lot of good questions

768
00:30:57,430 --> 00:30:54,799
coming in uh this first one is from t

769
00:30:59,430 --> 00:30:57,440
buttini on twitter and she wants to know

770
00:31:00,720 --> 00:30:59,440
are we talking about giant squids or

771
00:31:02,549 --> 00:31:00,730
algae and bacteria

772
00:31:05,029 --> 00:31:02,559
[Laughter]

773
00:31:06,950 --> 00:31:05,039
mary

774
00:31:09,190 --> 00:31:06,960
i think that most of us would be excited

775
00:31:10,950 --> 00:31:09,200
with any life um and we're certainly

776
00:31:13,510 --> 00:31:10,960
when we're talking about the sources of

777
00:31:15,430 --> 00:31:13,520
energy this is to feed the base of a

778
00:31:17,430 --> 00:31:15,440
food web so we're going to start with

779
00:31:19,909 --> 00:31:17,440
bacteria and if we get lucky maybe

780
00:31:21,590 --> 00:31:19,919
there's something that's larger

781
00:31:23,909 --> 00:31:21,600
you know i think what's really also

782
00:31:26,230 --> 00:31:23,919
exciting about these discoveries

783
00:31:30,149 --> 00:31:26,240
is these ocean worlds with the with

784
00:31:33,190 --> 00:31:30,159
their uh a protective uh outer shell if

785
00:31:36,070 --> 00:31:33,200
indeed there's life in there it it has

786
00:31:39,110 --> 00:31:36,080
to be completely different than ours in

787
00:31:41,190 --> 00:31:39,120
the sense that it's generated in a way

788
00:31:49,029 --> 00:31:41,200
that's not related to our life we call

789
00:31:53,350 --> 00:31:51,269
uh this second question is from decent

790
00:31:55,029 --> 00:31:53,360
matt sai on twitter and he wants to know

791
00:31:57,110 --> 00:31:55,039
could there be movement of ice

792
00:31:59,110 --> 00:31:57,120
surrounding enceladus driven by ocean

793
00:32:03,029 --> 00:31:59,120
convection currents similar to plate

794
00:32:06,789 --> 00:32:04,789
you know that's a really great question

795
00:32:09,830 --> 00:32:06,799
and the reason why is it was only within

796
00:32:13,750 --> 00:32:09,840
the last couple years that that we have

797
00:32:16,389 --> 00:32:13,760
started to look back at the europa data

798
00:32:18,149 --> 00:32:16,399
uh that has been gathered by galileo you

799
00:32:21,509 --> 00:32:18,159
know galileo only

800
00:32:24,470 --> 00:32:21,519
made like uh 10 or 11 flybys

801
00:32:26,789 --> 00:32:24,480
successfully by europa and so we have

802
00:32:29,430 --> 00:32:26,799
very limited images but there does

803
00:32:31,590 --> 00:32:29,440
appear to be a certain location for

804
00:32:34,710 --> 00:32:31,600
which some sort of subduction is going

805
00:32:36,870 --> 00:32:34,720
on in a crack where one element or plate

806
00:32:39,750 --> 00:32:36,880
of the of that uh

807
00:32:42,310 --> 00:32:39,760
icy shell is moving underneath another

808
00:32:44,870 --> 00:32:42,320
we don't know that that's true it may be

809
00:32:47,350 --> 00:32:44,880
in much greater locations all around

810
00:32:49,269 --> 00:32:47,360
that all around that body but you can

811
00:32:51,990 --> 00:32:49,279
understand the stresses when you think

812
00:32:54,070 --> 00:32:52,000
about the tidal forces europa is in an

813
00:32:56,470 --> 00:32:54,080
elliptical orbit

814
00:32:58,310 --> 00:32:56,480
around jupiter and it also has tidal

815
00:33:00,710 --> 00:32:58,320
forces being pushed around by the other

816
00:33:02,870 --> 00:33:00,720
galilean moons and so when it's close to

817
00:33:05,269 --> 00:33:02,880
jupiter gets squeezed and when it's

818
00:33:07,350 --> 00:33:05,279
further away it relaxes

819
00:33:10,630 --> 00:33:07,360
every two and a half to three days as it

820
00:33:12,950 --> 00:33:10,640
makes its orbit it is being squeezed and

821
00:33:16,389 --> 00:33:12,960
released and squeezed and released our

822
00:33:18,950 --> 00:33:16,399
estimate today is that the surface moves

823
00:33:20,710 --> 00:33:18,960
as much as 30 meters you know that's the

824
00:33:24,630 --> 00:33:20,720
height of an eight or nine story

825
00:33:27,269 --> 00:33:24,640
building every every two or three days

826
00:33:29,750 --> 00:33:27,279
that heat it's got to go somewhere and

827
00:33:33,509 --> 00:33:29,760
and the pushing and the stresses on on

828
00:33:35,029 --> 00:33:33,519
the icy shell may indeed uh be like our

829
00:33:36,310 --> 00:33:35,039
plate tectonics

830
00:33:37,430 --> 00:33:36,320
can i add one

831
00:33:39,990 --> 00:33:37,440
thing about it that actually is

832
00:33:42,389 --> 00:33:40,000
important for life so here on earth many

833
00:33:44,070 --> 00:33:42,399
people believe that we wouldn't have

834
00:33:46,070 --> 00:33:44,080
sustained life on earth if it weren't

835
00:33:49,269 --> 00:33:46,080
for plate tectonics oh

836
00:33:51,590 --> 00:33:49,279
and so it that kind of a process is very

837
00:33:53,990 --> 00:33:51,600
important on these icy moons as well

838
00:33:55,669 --> 00:33:54,000
because we think about

839
00:33:57,029 --> 00:33:55,679
we've just heard about some sources of

840
00:33:59,269 --> 00:33:57,039
energy that are coming from the

841
00:34:01,830 --> 00:33:59,279
interaction of the water and the core we

842
00:34:04,470 --> 00:34:01,840
also think on europa there are creations

843
00:34:07,430 --> 00:34:04,480
of oxidants at the surface as a result

844
00:34:10,629 --> 00:34:07,440
of the radiation at the surface and we

845
00:34:13,510 --> 00:34:10,639
need some sort of active shell

846
00:34:16,310 --> 00:34:13,520
a ice tectonics if you will to actually

847
00:34:18,869 --> 00:34:16,320
bring those into contact much like a

848
00:34:20,470 --> 00:34:18,879
battery where you have a positive and a

849
00:34:23,030 --> 00:34:20,480
negative pull

850
00:34:24,710 --> 00:34:23,040
to actually connect to drive life and so

851
00:34:25,750 --> 00:34:24,720
this process is really important for

852
00:34:27,510 --> 00:34:25,760
life

853
00:34:28,710 --> 00:34:27,520
okay well thank you very much we're

854
00:34:30,149 --> 00:34:28,720
going to take one more question to

855
00:34:33,510 --> 00:34:30,159
social media and then we're going to go

856
00:34:35,349 --> 00:34:33,520
to the phone lines so emily sure this

857
00:34:36,950 --> 00:34:35,359
question is from philip on facebook and

858
00:34:38,950 --> 00:34:36,960
he wants to know which moon do you think

859
00:34:41,589 --> 00:34:38,960
offers more possibility of life on it

860
00:34:43,589 --> 00:34:41,599
europa or enceladus

861
00:34:45,589 --> 00:34:43,599
well that's a good good that's a great

862
00:34:47,589 --> 00:34:45,599
question i wish i knew for sure i

863
00:34:49,669 --> 00:34:47,599
haven't i haven't all right mary mary

864
00:34:52,310 --> 00:34:49,679
will give her give it a shot well so i

865
00:34:53,909 --> 00:34:52,320
think that this result of finding um

866
00:34:55,750 --> 00:34:53,919
such a significant amount of

867
00:34:58,390 --> 00:34:55,760
hydrothermal activity and a lot of

868
00:35:01,030 --> 00:34:58,400
hydrogen is incredible it speaks to the

869
00:35:04,310 --> 00:35:01,040
habitability on the other hand it also

870
00:35:06,390 --> 00:35:04,320
the fact that we can measure such

871
00:35:09,030 --> 00:35:06,400
high concentrations of hydrogen and

872
00:35:11,829 --> 00:35:09,040
carbon dioxide means that there might

873
00:35:14,230 --> 00:35:11,839
not be life there at all and if there is

874
00:35:17,910 --> 00:35:14,240
life it's not very active because when

875
00:35:20,230 --> 00:35:17,920
you have those stacks of pizza much like

876
00:35:22,790 --> 00:35:20,240
in a graduate school department it

877
00:35:25,349 --> 00:35:22,800
disappears so we have this build up of

878
00:35:27,510 --> 00:35:25,359
food that's not being used and part of

879
00:35:29,190 --> 00:35:27,520
that could be because we think enceladus

880
00:35:31,109 --> 00:35:29,200
might be fairly young

881
00:35:32,470 --> 00:35:31,119
on the other hand if the same process

882
00:35:34,790 --> 00:35:32,480
which there's no reason to think it

883
00:35:36,710 --> 00:35:34,800
wouldn't be happening on europa we know

884
00:35:38,790 --> 00:35:36,720
that europa and the moons around jupiter

885
00:35:41,270 --> 00:35:38,800
were formed four billion years ago so

886
00:35:42,950 --> 00:35:41,280
that's a lot more time for life to have

887
00:35:46,150 --> 00:35:42,960
emerged and start taking advantage of

888
00:35:47,829 --> 00:35:46,160
these energy sources so my money for the

889
00:35:49,589 --> 00:35:47,839
moment um

890
00:35:51,270 --> 00:35:49,599
is still on europa

891
00:35:53,349 --> 00:35:51,280
uh but this that

892
00:35:55,109 --> 00:35:53,359
but it could be any on any of these

893
00:35:56,829 --> 00:35:55,119
moons and certainly would be great if it

894
00:35:58,390 --> 00:35:56,839
was on in all of

895
00:36:00,150 --> 00:35:58,400
them

896
00:36:02,390 --> 00:36:00,160
well thank you so much

897
00:36:07,030 --> 00:36:02,400
next we have mike wahl from space.com

898
00:36:09,990 --> 00:36:08,390
yep i'm here

899
00:36:12,310 --> 00:36:10,000
thank you guys um this is really

900
00:36:13,990 --> 00:36:12,320
exciting stuff and like i have another

901
00:36:15,430 --> 00:36:14,000
question for actually bill about the

902
00:36:16,470 --> 00:36:15,440
plumes um

903
00:36:20,470 --> 00:36:16,480
so

904
00:36:22,310 --> 00:36:20,480
on this this is not a confirmation that

905
00:36:23,910 --> 00:36:22,320
the plumes exist i mean i know you guys

906
00:36:25,750 --> 00:36:23,920
i keep seeing more and more signs but

907
00:36:28,390 --> 00:36:25,760
you're but you're stopping short of

908
00:36:29,190 --> 00:36:28,400
saying that that they definitely exist

909
00:36:33,910 --> 00:36:29,200
and

910
00:36:36,630 --> 00:36:33,920
same location as as the original 2012

911
00:36:37,750 --> 00:36:36,640
detection or like do the plumes i mean

912
00:36:39,430 --> 00:36:37,760
have they been spotted in multiple

913
00:36:40,790 --> 00:36:39,440
locations

914
00:36:43,109 --> 00:36:40,800
around europa

915
00:36:44,870 --> 00:36:43,119
thank you

916
00:36:47,510 --> 00:36:44,880
yeah let's have bill sparks of course

917
00:36:52,390 --> 00:36:49,430
okay um

918
00:36:55,910 --> 00:36:52,400
it's not completely unequivocal but in

919
00:36:59,190 --> 00:36:55,920
my mind the pendulum has uh swung from

920
00:37:01,349 --> 00:36:59,200
uh caution to optimism

921
00:37:04,470 --> 00:37:01,359
the evidence is growing the fact that we

922
00:37:05,829 --> 00:37:04,480
saw a repeat at the exact same location

923
00:37:07,589 --> 00:37:05,839
that's one of the

924
00:37:09,670 --> 00:37:07,599
gold standards for

925
00:37:11,990 --> 00:37:09,680
dealing with an intermittent phenomenon

926
00:37:13,910 --> 00:37:12,000
it's not proof because we're right at

927
00:37:16,069 --> 00:37:13,920
the limit of what

928
00:37:19,030 --> 00:37:16,079
the hubble can do

929
00:37:21,190 --> 00:37:19,040
it's not completely unequivocal the way

930
00:37:23,670 --> 00:37:21,200
it is on enceladus so on enceladus

931
00:37:25,990 --> 00:37:23,680
you've got movies of the of the plumes

932
00:37:28,390 --> 00:37:26,000
and you've got wonderful maps and uh

933
00:37:30,790 --> 00:37:28,400
temperature maps and mass spectrometer

934
00:37:33,109 --> 00:37:30,800
measurements of the composition uh and

935
00:37:34,950 --> 00:37:33,119
we've got a little smudge uh next to an

936
00:37:37,190 --> 00:37:34,960
image from the hubble and you know it's

937
00:37:38,550 --> 00:37:37,200
a fantastic image and it's but it's

938
00:37:39,510 --> 00:37:38,560
right at the limit of what the hubble

939
00:37:41,990 --> 00:37:39,520
can do

940
00:37:43,910 --> 00:37:42,000
the fact that we've got to repeat uh

941
00:37:46,630 --> 00:37:43,920
tells you that in a formal statistical

942
00:37:48,870 --> 00:37:46,640
sense it can't happen by chance

943
00:37:51,349 --> 00:37:48,880
so we have to look for

944
00:37:53,829 --> 00:37:51,359
systematic effects that might cause it

945
00:37:55,910 --> 00:37:53,839
we don't know of any which is why uh

946
00:37:58,390 --> 00:37:55,920
most of us some of us are leaning

947
00:38:00,150 --> 00:37:58,400
towards thinking that this is uh this

948
00:38:02,230 --> 00:38:00,160
this means they're real

949
00:38:03,030 --> 00:38:02,240
and then the secondary information with

950
00:38:08,870 --> 00:38:03,040
the

951
00:38:11,270 --> 00:38:08,880
imaging that

952
00:38:13,270 --> 00:38:11,280
gives you some additional statistical

953
00:38:14,310 --> 00:38:13,280
evidence that in fact

954
00:38:16,390 --> 00:38:14,320
they're real

955
00:38:18,630 --> 00:38:16,400
it doesn't prove it because you know

956
00:38:19,910 --> 00:38:18,640
unfortunate coincidences can happen in

957
00:38:22,630 --> 00:38:19,920
the world

958
00:38:25,430 --> 00:38:22,640
in terms of the location uh the original

959
00:38:28,710 --> 00:38:25,440
uh detection by the roth team was around

960
00:38:31,670 --> 00:38:28,720
the south polar region uh these are the

961
00:38:33,190 --> 00:38:31,680
dissociation products of water

962
00:38:36,710 --> 00:38:33,200
in

963
00:38:39,910 --> 00:38:36,720
high altitude down around the south pole

964
00:38:41,750 --> 00:38:39,920
and uh in our transit observations where

965
00:38:45,190 --> 00:38:41,760
we were looking for absorbing material

966
00:38:46,630 --> 00:38:45,200
around europa uh we did see a couple of

967
00:38:50,470 --> 00:38:46,640
uh

968
00:38:52,390 --> 00:38:50,480
of features in that in in that area

969
00:38:55,349 --> 00:38:52,400
but it's harder to localize things

970
00:38:57,670 --> 00:38:55,359
around the poles this particular one

971
00:38:59,670 --> 00:38:57,680
was well localized it wasn't quite as

972
00:39:01,349 --> 00:38:59,680
high as the previous one and that's the

973
00:39:05,670 --> 00:39:01,359
one that repeated and so that's really

974
00:39:08,710 --> 00:39:07,109
thank you

975
00:39:11,270 --> 00:39:08,720
there's couple other pieces of evidence

976
00:39:13,510 --> 00:39:11,280
that i think is also really tantalizing

977
00:39:15,190 --> 00:39:13,520
you know when we look at enceladus

978
00:39:17,750 --> 00:39:15,200
particularly around those tiger straps

979
00:39:21,270 --> 00:39:17,760
there's absolutely no craters they're

980
00:39:24,069 --> 00:39:21,280
completely filled in as you go to

981
00:39:24,950 --> 00:39:24,079
the mid-latitudes and up to the north

982
00:39:27,910 --> 00:39:24,960
pole

983
00:39:29,349 --> 00:39:27,920
of enceladus you see you do indeed see a

984
00:39:33,190 --> 00:39:29,359
number of craters

985
00:39:36,150 --> 00:39:33,200
if we look now at europa we can hardly

986
00:39:39,270 --> 00:39:36,160
see any craters this has always been a

987
00:39:42,710 --> 00:39:39,280
big puzzle in terms of how this surface

988
00:39:45,030 --> 00:39:42,720
is morphing eliminating the craters that

989
00:39:48,230 --> 00:39:45,040
must have been there at one time and are

990
00:39:50,150 --> 00:39:48,240
continually bombarding the body but over

991
00:39:52,390 --> 00:39:50,160
the length of time that we've observed

992
00:39:55,190 --> 00:39:52,400
it with the galileo mission those

993
00:39:56,390 --> 00:39:55,200
several years only a handful of craters

994
00:39:59,829 --> 00:39:56,400
were found

995
00:40:01,430 --> 00:39:59,839
the plumes the plume idea that it is

996
00:40:03,270 --> 00:40:01,440
resurfacing

997
00:40:05,190 --> 00:40:03,280
and the subduction

998
00:40:07,910 --> 00:40:05,200
must be connected in a way that is

999
00:40:11,670 --> 00:40:07,920
eliminating those craters so this fits

1000
00:40:15,190 --> 00:40:11,680
perfectly with these observations

1001
00:40:19,910 --> 00:40:17,910
so um next we have two questions on the

1002
00:40:23,270 --> 00:40:19,920
phone line then we're going to go ahead

1003
00:40:25,349 --> 00:40:23,280
and go to social media so the first

1004
00:40:27,750 --> 00:40:25,359
call-in person we have is keith cowing

1005
00:40:29,589 --> 00:40:27,760
from nasa watch keith

1006
00:40:31,190 --> 00:40:29,599
a two-part question for thomas sir

1007
00:40:33,430 --> 00:40:31,200
brooke and first of all

1008
00:40:35,910 --> 00:40:33,440
several years ago nasa was directed to

1009
00:40:37,990 --> 00:40:35,920
create an ocean world's program now i

1010
00:40:40,550 --> 00:40:38,000
see that phrase everywhere but have you

1011
00:40:43,030 --> 00:40:40,560
formally established a program office is

1012
00:40:45,109 --> 00:40:43,040
who's in charge of it what's the budget

1013
00:40:46,790 --> 00:40:45,119
and second of all a question um why is

1014
00:40:49,670 --> 00:40:46,800
it that some news media were given

1015
00:40:52,069 --> 00:40:49,680
advance access to nasa personnel

1016
00:40:55,750 --> 00:40:52,079
on this taxpayer-funded research and

1017
00:40:58,950 --> 00:40:57,030
so uh

1018
00:41:01,190 --> 00:40:58,960
let me certainly take uh on the first

1019
00:41:03,109 --> 00:41:01,200
one as head of planetary science and we

1020
00:41:06,309 --> 00:41:03,119
did indeed receive congressional

1021
00:41:07,829 --> 00:41:06,319
direction about establishing an ocean

1022
00:41:10,069 --> 00:41:07,839
world's program

1023
00:41:12,950 --> 00:41:10,079
we have indeed communicated

1024
00:41:15,030 --> 00:41:12,960
back to congress uh in our budgetary

1025
00:41:16,309 --> 00:41:15,040
aspects that we are

1026
00:41:18,550 --> 00:41:16,319
doing that

1027
00:41:21,030 --> 00:41:18,560
in with respect to

1028
00:41:24,870 --> 00:41:21,040
the next set of missions and that next

1029
00:41:28,390 --> 00:41:24,880
set is indeed the europa clipper mission

1030
00:41:29,270 --> 00:41:28,400
uh as far as um uh the press interaction

1031
00:41:33,270 --> 00:41:29,280
that's

1032
00:41:35,190 --> 00:41:33,280
were directed to establish a program for

1033
00:41:38,309 --> 00:41:35,200
investigating ocean worlds and we went

1034
00:41:40,550 --> 00:41:38,319
to our outer planets assessment group

1035
00:41:42,470 --> 00:41:40,560
and asked them to help us out by

1036
00:41:44,870 --> 00:41:42,480
developing a road map for exploring

1037
00:41:46,950 --> 00:41:44,880
these worlds and that is in pro in

1038
00:41:50,390 --> 00:41:46,960
process they're about to deliver to that

1039
00:41:52,950 --> 00:41:50,400
to us any day now or any month now week

1040
00:41:55,190 --> 00:41:52,960
um and so we're moving forward on

1041
00:41:57,510 --> 00:41:55,200
setting the science as we always do

1042
00:41:59,030 --> 00:41:57,520
setting the science priorities and then

1043
00:42:01,030 --> 00:41:59,040
filling in the technologies that we're

1044
00:42:02,550 --> 00:42:01,040
going to need for it and and and

1045
00:42:04,630 --> 00:42:02,560
discussing the types of missions those

1046
00:42:07,349 --> 00:42:04,640
would look like to the various ocean

1047
00:42:10,150 --> 00:42:07,359
worlds that we have to explore

1048
00:42:12,309 --> 00:42:10,160
next we have tracy watson from usa today

1049
00:42:14,550 --> 00:42:12,319
tracy

1050
00:42:16,470 --> 00:42:14,560
hi thank you for dr green

1051
00:42:18,950 --> 00:42:16,480
can you talk about now how this mission

1052
00:42:20,630 --> 00:42:18,960
affects your desire to send

1053
00:42:23,829 --> 00:42:20,640
excuse me how these results affect your

1054
00:42:26,069 --> 00:42:23,839
desire to send a mission to and sell

1055
00:42:29,349 --> 00:42:26,079
this does this make it kind of rise to

1056
00:42:32,790 --> 00:42:29,359
the top of what should be next thanks

1057
00:42:35,270 --> 00:42:32,800
well indeed we announced in january uh a

1058
00:42:38,550 --> 00:42:35,280
program called new frontiers

1059
00:42:41,430 --> 00:42:38,560
and that is a very targeted list of of

1060
00:42:44,790 --> 00:42:41,440
of objects and on that list turns out to

1061
00:42:47,510 --> 00:42:44,800
be enceladus this is an element indeed

1062
00:42:49,670 --> 00:42:47,520
of recognition that this is an active

1063
00:42:51,109 --> 00:42:49,680
world that this is new discoveries that

1064
00:42:53,990 --> 00:42:51,119
have been made

1065
00:42:56,470 --> 00:42:54,000
by cassini since the time our planetary

1066
00:42:59,910 --> 00:42:56,480
decadal actually identified what those

1067
00:43:02,230 --> 00:42:59,920
targets are so uh that's in competition

1068
00:43:04,390 --> 00:43:02,240
right now and and we'll be receiving the

1069
00:43:06,870 --> 00:43:04,400
proposals uh soon and we'll be

1070
00:43:09,190 --> 00:43:06,880
evaluating them and announcing the the

1071
00:43:12,230 --> 00:43:09,200
uh the step one select these by the end

1072
00:43:13,990 --> 00:43:12,240
of the calendar year is what we hope

1073
00:43:16,870 --> 00:43:14,000
thanks jim uh next we're going to go to

1074
00:43:18,870 --> 00:43:16,880
social media so emily what are uh the

1075
00:43:20,390 --> 00:43:18,880
netizens talking about today

1076
00:43:22,710 --> 00:43:20,400
yeah there's a lot of interest on social

1077
00:43:25,030 --> 00:43:22,720
media um this question is from lorenzo

1078
00:43:27,270 --> 00:43:25,040
on facebook so the juno spacecraft just

1079
00:43:29,030 --> 00:43:27,280
recently went into orbit around jupiter

1080
00:43:30,950 --> 00:43:29,040
is there any possibility for that

1081
00:43:32,550 --> 00:43:30,960
spacecraft to help with

1082
00:43:34,309 --> 00:43:32,560
observations of the balloons around

1083
00:43:36,390 --> 00:43:34,319
europa

1084
00:43:39,270 --> 00:43:36,400
well indeed

1085
00:43:41,430 --> 00:43:39,280
juno was launched in 2011

1086
00:43:44,150 --> 00:43:41,440
we may have had a hint of the plumes of

1087
00:43:47,670 --> 00:43:44,160
course from cassini but absolutely

1088
00:43:50,550 --> 00:43:47,680
nothing from europa by that time and so

1089
00:43:53,270 --> 00:43:50,560
it's concentrating on really orbiting

1090
00:43:56,230 --> 00:43:53,280
jupiter and understanding the structure

1091
00:43:59,030 --> 00:43:56,240
that large uh planet the you know the

1092
00:44:02,150 --> 00:43:59,040
largest planet in our solar system it

1093
00:44:04,710 --> 00:44:02,160
also is uh uh so important to understand

1094
00:44:07,670 --> 00:44:04,720
that because the the remnants

1095
00:44:09,510 --> 00:44:07,680
left over after jupiter and sun accreted

1096
00:44:11,510 --> 00:44:09,520
was the rest of the solar system so

1097
00:44:13,990 --> 00:44:11,520
we're really really quite interested in

1098
00:44:15,670 --> 00:44:14,000
understanding the origin and evolution

1099
00:44:18,069 --> 00:44:15,680
of our solar system and understanding

1100
00:44:20,790 --> 00:44:18,079
how jupiter was put together is a major

1101
00:44:25,510 --> 00:44:20,800
segment of that so unfortunately

1102
00:44:29,109 --> 00:44:27,030
all right this next one is from carrie

1103
00:44:30,790 --> 00:44:29,119
on facebook uh they want to know what

1104
00:44:34,710 --> 00:44:30,800
chemicals are causing the coloration

1105
00:44:39,589 --> 00:44:37,589
so with that uh perhaps uh

1106
00:44:42,390 --> 00:44:39,599
uh goddard could talk a little bit about

1107
00:44:46,470 --> 00:44:45,190
uh i think the short answer is we don't

1108
00:44:48,870 --> 00:44:46,480
know uh

1109
00:44:50,870 --> 00:44:48,880
there are the skins that they're salts

1110
00:44:53,430 --> 00:44:50,880
from the ocean but it's not known what

1111
00:44:55,510 --> 00:44:53,440
sort of salts and that potentially

1112
00:44:58,790 --> 00:44:55,520
there's a contribution from

1113
00:45:02,230 --> 00:44:58,800
uh the jovian magnetosphere of irons

1114
00:45:03,910 --> 00:45:02,240
being implanted from io the next moon in

1115
00:45:07,030 --> 00:45:03,920
that's definitely

1116
00:45:08,630 --> 00:45:07,040
got plumes it's got sulfur volcanoes

1117
00:45:09,990 --> 00:45:08,640
spraying sulfur into the whole

1118
00:45:12,390 --> 00:45:10,000
environment

1119
00:45:14,630 --> 00:45:12,400
but the detailed composition

1120
00:45:16,630 --> 00:45:14,640
of the cracks and the dark areas it's a

1121
00:45:19,190 --> 00:45:16,640
it's an ongoing study

1122
00:45:20,390 --> 00:45:19,200
for of research uh people are trying to

1123
00:45:23,030 --> 00:45:20,400
find out it's obviously a very

1124
00:45:24,870 --> 00:45:23,040
interesting question and uh

1125
00:45:27,430 --> 00:45:24,880
it's it will be very nice to know the

1126
00:45:29,030 --> 00:45:27,440
answer to that

1127
00:45:30,950 --> 00:45:29,040
all right we'll take one more question

1128
00:45:33,030 --> 00:45:30,960
from social

1129
00:45:34,550 --> 00:45:33,040
awesome media one's from stephanie on

1130
00:45:36,230 --> 00:45:34,560
twitter she wants to know what

1131
00:45:39,750 --> 00:45:36,240
instruments will be needed to detect

1132
00:45:41,030 --> 00:45:39,760
life on enceladus and how can we help

1133
00:45:46,630 --> 00:45:41,040
okay

1134
00:45:50,550 --> 00:45:48,230
all right um

1135
00:45:53,430 --> 00:45:50,560
well the instrument excuse me the

1136
00:45:55,430 --> 00:45:53,440
instrumentation that uh would be

1137
00:45:57,510 --> 00:45:55,440
uh could be told in this regard are

1138
00:46:00,230 --> 00:45:57,520
similar instruments to the ones that we

1139
00:46:01,910 --> 00:46:00,240
were flying on cassini they're

1140
00:46:03,589 --> 00:46:01,920
and they're certainly similar to the

1141
00:46:07,670 --> 00:46:03,599
instruments that are presently flying on

1142
00:46:09,910 --> 00:46:07,680
europa the mass spectrometer and

1143
00:46:13,270 --> 00:46:09,920
dust analyzer

1144
00:46:16,069 --> 00:46:13,280
are both important in determining this

1145
00:46:17,990 --> 00:46:16,079
habitability as well as looking for

1146
00:46:19,510 --> 00:46:18,000
perhaps amino acids

1147
00:46:23,510 --> 00:46:19,520
fatty acids

1148
00:46:24,550 --> 00:46:23,520
looking at isotopic ratios and trying to

1149
00:46:25,750 --> 00:46:24,560
determine

1150
00:46:29,030 --> 00:46:25,760
uh

1151
00:46:31,349 --> 00:46:29,040
signs of life as well as telling us more

1152
00:46:32,550 --> 00:46:31,359
about the habitability

1153
00:46:34,950 --> 00:46:32,560
learning a little bit about the

1154
00:46:36,870 --> 00:46:34,960
structure of the molecules themselves

1155
00:46:39,030 --> 00:46:36,880
would also be beneficial

1156
00:46:41,349 --> 00:46:39,040
and that can be done through tandem mass

1157
00:46:42,470 --> 00:46:41,359
spectrometry

1158
00:46:44,710 --> 00:46:42,480
there are certainly

1159
00:46:46,950 --> 00:46:44,720
other techniques that are being studied

1160
00:46:49,750 --> 00:46:46,960
for landers but for fly-through missions

1161
00:46:52,390 --> 00:46:49,760
which we think would be uh good enough

1162
00:46:54,790 --> 00:46:52,400
in the case of enceladus uh

1163
00:46:58,230 --> 00:46:54,800
this is the this is a next step that

1164
00:47:00,790 --> 00:46:58,240
would be a good a good approach

1165
00:47:02,870 --> 00:47:00,800
thank you now so before we close um jim

1166
00:47:05,510 --> 00:47:02,880
can you give us some closing thoughts um

1167
00:47:07,910 --> 00:47:05,520
anything you'd like to talk about

1168
00:47:11,030 --> 00:47:07,920
indeed you know this is really an

1169
00:47:13,589 --> 00:47:11,040
exciting time our science is proceeding

1170
00:47:15,190 --> 00:47:13,599
so rapidly we can hardly keep up with

1171
00:47:16,150 --> 00:47:15,200
these discoveries

1172
00:47:18,309 --> 00:47:16,160
you know

1173
00:47:20,630 --> 00:47:18,319
we really are looking forward to more of

1174
00:47:23,430 --> 00:47:20,640
the hubble observations

1175
00:47:25,990 --> 00:47:23,440
we may find that europa is far more

1176
00:47:28,950 --> 00:47:26,000
active in terms of not only one location

1177
00:47:31,270 --> 00:47:28,960
but a number of locations and that bodes

1178
00:47:32,870 --> 00:47:31,280
well with as i mentioned earlier filling

1179
00:47:35,430 --> 00:47:32,880
in these craters

1180
00:47:36,790 --> 00:47:35,440
these ocean worlds have just been

1181
00:47:39,750 --> 00:47:36,800
discovered

1182
00:47:41,910 --> 00:47:39,760
there are in our solar system we need to

1183
00:47:44,309 --> 00:47:41,920
probe them because they are one of the

1184
00:47:48,069 --> 00:47:44,319
best locations we believe

1185
00:47:49,510 --> 00:47:48,079
that may harbor life today

1186
00:47:51,990 --> 00:47:49,520
thank you and that's all the time that

1187
00:47:55,910 --> 00:47:52,000
we have left please keep those questions

1188
00:47:58,309 --> 00:47:55,920
coming online using the hashtag asknasa

1189
00:47:59,910 --> 00:47:58,319
before be sure to follow us on all our

1190
00:48:02,390 --> 00:47:59,920
social media

1191
00:48:04,950 --> 00:48:02,400
and for more information please visit