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[Music]

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as per the said I work with dr. Brittany

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Schmidt here at Georgia Tech and we do

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kind of three-part science so we're NASA

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Pew Start program which is about 50/50

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science and engineering development for

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kind of solar system the ocean world

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exploration not give a good introduction

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to ocean worlds and is the first talk of

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this session I'm going to dive into that

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a little bit deeper but we can also do a

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lot of climate science and the analog

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environments that we work in Antarctica

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are kind of relevant for some of the

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terrestrial work as well so that said

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here you can see this is the edge of the

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Ross Ice Shelf and after a couple years

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working in Antarctica this is the first

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time I saw this just this past November

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it's pretty well it's about a 300 meter

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thick chunk of ice so the part that's

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sticking up here is about 30 meters or a

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hundred feet and this is kind of the

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system that we're interested in studying

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as an analog for ocean world in our

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solar system what are the processes that

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are going on below the large ice sheets

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on earth and how good are those as an

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analogue what are the limits of

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habitability and sort of non-photo quota

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Goshen's alright backing up a little bit

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to ocean worlds so the planets moons

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that have oceans this kind of breaks our

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understanding of the habitable zone a

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little bit because most of these places

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are places that are not within the sort

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of nominal Heather zone where you go

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Venus to Mars for our system where so

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the exoplanet systems a lot of them are

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out by Jupiter or Saturn and their moons

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of main planets too so these are

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environments that were really interested

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in for our solar system that are not

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kind of in the traditional habitable

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zone so Jonathan we mean 2017 here at a

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great kind of review paper on what a lot

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of these bodies are and some of the

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processes they are affecting though this

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is one of the tables that summarizes it

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we can focus on those that are extant

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here that means that there's good

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evidence for places that have currently

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habitable environments or oceans so the

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reason that this is possible outside of

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the habitable zone is from a few

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different mechanisms so one you just

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have your eminent and heat of formation

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so 4.5 billion years ago or so these

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bodies form and they've been cooling off

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ever since

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radioactive decay in the interior from

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radiogenic elements that's another way

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of just constantly generating heat but

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really interesting and foremost these

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bodies because they're moons

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orbiting their host planets and slightly

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eccentric orbits this title dissipation

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- basically a stress ball that's getting

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squeezed as they spin around in these

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eccentric orbits and that frictional

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heating actually provides enough heat to

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people a lot of these places liquid so

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moving on to that yeah these ones were

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interested in Europa and saw this and

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potentially tighten things a little bit

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more complicated because of the pressure

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regime and so there's kind of a weird

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sandwich of ice ocean and methane on the

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surface all kinds of strangeness there

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some people here work on that but we're

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gonna focus on kind of a simpler model

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where like earth you have a rocky core

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you have an ocean layer and then an ice

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surface so well look at your open as an

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example again kind of the the structure

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not talked about this a little bit and

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then moving on to the zoomed in view of

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that this is from the Europa Lander SDT

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NASA is currently trying to think if

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that's a good idea of saying oh I'll

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land into the surface of Europa

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something we can do in the next decade

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or so but yeah so not talked about how

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we know there's an ocean there from a

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lot of the magnetometry data and we

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think that this ocean layer this Brian

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layer here the salty layer that's

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conductive is what's driving that

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observation and that's very good

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evidence for that but above that you

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have a cross-device ocean maybe 100

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kilometers thick we don't really know

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maybe a total length or thickness of

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water layer ice and ocean and about 140

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kilometers or so and then people are

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really interested about what's going on

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in the seafloor where are the reductants

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where the oxidants coming from this

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system is this something where you could

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have life what are the limits of

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habitability in an ice-covered

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ecosystems should they exist on other

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planets we use Antarctica as an analogue

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to ask that question here all right go

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as soon as you're pregnant

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okay we're back maybe yeah so my

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personal research goals are to

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characterize both the physical processes

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and the biology underneath I shelves in

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Antarctica and look at the intersections

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and how these things interact and what

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controls both biological systems can

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place in the physical systems and the

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physical systems place in the biological

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systems in terms of looking about

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looking at where the habitable

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environments are distributed and where

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things might live and then take that

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extrapolate it to Europa and other

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systems like that to guide and provide

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context for where you might best want to

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land on Europa or look for it in the

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ocean look for habitable or bio

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signatures in the ocean again in

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Antarctica so the processes that we're

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really interested in is the this this

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depth temperature and salinity dependent

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ice box

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because as ice is moving around

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underneath it's in training organics

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it's controlling where things can live

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at that ice ocean interface and that's a

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process that's likely ongoing at Europe

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as well and that can control where

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organics are getting incorporated in the

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VHL where you might want to land with

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the lander we look at the symmetry

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basically POG refer it's also kind of an

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unconstrained thing it's really hard to

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get observations underneath these ice

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shelves this is actually report from the

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2014 ocean observatory something like

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that symposium I think they're like well

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how can we understand these problems

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usually we drill a hole we put a mooring

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down and we can get like kind of one

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point measurement of what's going on but

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we're trying to expand that a little bit

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so we can understand the industry in the

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topography in the processes in a broader

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spatial scale and then from that how are

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we controlling to have lanisha's we have

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a few early observations of life

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underneath this ice shelf the Ross for

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examples a thousand kilometers wide so

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there's life under there and it's not

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entirely clear what's powering those

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ecosystem so we're trying to understand

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that the community make up what

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microbial systems are providing the sort

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of the base of the ecosystem how does

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that change from the open ocean to the

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back of the shelf and where these

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interesting nutrients coming from and

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what from that can we apply ocean wells

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so this is kind of our field site we do

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a lot of field work it's mostly field

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work actually this is Antarctica the

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Ross Ice Shelf about a thousand

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kilometres from the northern edge at the

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bottom here the top the stars are our

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field sites we do most of our work right

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about here by McMurdo Station which

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largest US base next to the New Zealand

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days this is another site about midway

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and then finally a site at the grounding

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zone where the ice goes of float so an

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ocean an ice shelf is a sort of a

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floating glacier to fly she started with

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that but again we're interested in how

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things change from the photic ocean we

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do photosynthesis driving a lot of life

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to the currents they might be dragging

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some of that detrital material

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underneath empowering the ecosystems to

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sort of all the way back at the base of

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the ice shelf how things are surviving

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back there we know there's there's life

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back there so again that gradient okay

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so field data what do we use to do this

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we've built an underwater vehicle here

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at Tech it's almost it's twelve feet

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three now meters longer so it's very

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small diameter we've designed it to fit

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through bore holes because it's very

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hard to drive in from the front of the

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show if you can't get very far so we've

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kind of got this like have robot will

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travel model or anyone who's doing a

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climate study on earth they're putting a

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borehole in putting a mooring in or

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something like that we can also go along

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and deploy the robot and increase the

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science return we've got some standard

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sensors here so in the front we have

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sonar helps us not run into things Ct is

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conductivity and temperature proxy for

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salinity and temperature do dissolved

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oxygen some camera systems some lasers

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for scale get a scale in the imaging

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systems and then we've got kind of a

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science module here side scan sonar for

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mapping the seafloor sea Dom which is

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dissolved organic materials which kind

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of helps you understand communication

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with the open ocean pH ORP which is

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interesting if you might try to find a

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hydrothermal vent or somewhere we other

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a disequilibrium of compounds community

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for turbidity also good for hydrothermal

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systems

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section and again cameras laser scales

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lights etc so it's designed to be

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modular and we also have some people at

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Tech that are helping to develop sensors

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for future ocean world exploration like

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cell calendars or holographic

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microscopes and using Iceland as a sort

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of a payload carrier for that okay so

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this is kind of what that looks like

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from the surface this is out next to

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Erebus which is one of the larger

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volcanoes and Antarctica we've got our

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little are called the a-frame here it's

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just an aluminum structure we built

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drill a hole in the ice the holes right

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down there and then I spin will hang

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from here and then dive down below I've

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got these little tracked vehicles here

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which is kind of how we get around the

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ice

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generators pens etc and this is what

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that looks like underneath the water

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which is kind of cool so here you can

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see we've got our lights on so recording

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some some science data here we've got

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side scan sonar running we use a

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fiber-optic tether for your live data

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recovery of course you can't transmit

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other than acoustic signals you can't

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really transmit data very very well

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through water and then this is what

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another way we can get some some data we

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can just go out on snow machines drill

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some holes is my adviser here dr.

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Schmidt and she's got we call this

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Cassini it's one of our labs most

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productive sensors it's a CT sensitive

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we can just take wherever we go drop it

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through the ice somewhere spot and then

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we get kind of close point profiles I

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really what we're trying to do is

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understand those environments across

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this gradient and then tie that back to

275
00:09:22,680 --> 00:09:19,870
the processes they're influencing the

276
00:09:24,360 --> 00:09:22,690
biology that can be present there so

277
00:09:26,610 --> 00:09:24,370
starting from the front of the shelf

278
00:09:29,250 --> 00:09:26,620
what we do this is kind of where the the

279
00:09:30,840 --> 00:09:29,260
station is and then this is an overview

280
00:09:32,010 --> 00:09:30,850
of all the historical observations that

281
00:09:34,920 --> 00:09:32,020
have gone on underneath the Ross Ice

282
00:09:36,690 --> 00:09:34,930
Shelf for example so here we've got a

283
00:09:38,070 --> 00:09:36,700
lot of our work at the edges we're kind

284
00:09:40,590 --> 00:09:38,080
of tuning up our systems in practicing

285
00:09:42,449 --> 00:09:40,600
and Zed that's the Antarctic New Zealand

286
00:09:43,710 --> 00:09:42,459
program they just put a borehole in 2017

287
00:09:46,500 --> 00:09:43,720
they're collaborators with us a couple

288
00:09:48,030 --> 00:09:46,510
months ago the Ross Ice Shelf project

289
00:09:49,860 --> 00:09:48,040
there was a massive effort in the late

290
00:09:51,000 --> 00:09:49,870
70s to put a borehole and people really

291
00:09:53,850 --> 00:09:51,010
curious about what's going on in these

292
00:09:55,680 --> 00:09:53,860
ice shelves today went down they found

293
00:09:57,570 --> 00:09:55,690
some fish and things like that and then

294
00:09:59,040 --> 00:09:57,580
next year we're going down with New

295
00:10:01,260 --> 00:09:59,050
Zealand or actually excuse me

296
00:10:03,390 --> 00:10:01,270
I think we just bumped this back to next

297
00:10:04,380 --> 00:10:03,400
next year so we're gonna wait one more

298
00:10:06,180 --> 00:10:04,390
year but then do some drilling at the

299
00:10:08,820 --> 00:10:06,190
grounding zone and kind of expand our

300
00:10:12,180 --> 00:10:08,830
observations that ice bin and so this

301
00:10:13,680 --> 00:10:12,190
process of how water is moving and where

302
00:10:15,540 --> 00:10:13,690
ice is melting at the base of the Shelf

303
00:10:17,460 --> 00:10:15,550
or creating at the base of the shelf

304
00:10:20,280 --> 00:10:17,470
really controls what kind of biology we

305
00:10:22,019 --> 00:10:20,290
biology we observe so at the front you

306
00:10:23,579 --> 00:10:22,029
can see there's kind of lady crystal

307
00:10:24,630 --> 00:10:23,589
textures you have things like amphipods

308
00:10:25,860 --> 00:10:24,640
that are hanging out in the water column

309
00:10:27,150 --> 00:10:25,870
and they're filtered feeding off of

310
00:10:28,829 --> 00:10:27,160
material that's coming in from the open

311
00:10:30,840 --> 00:10:28,839
ocean that's probably not our best

312
00:10:32,610 --> 00:10:30,850
analog for an ocean world not really a

313
00:10:33,470 --> 00:10:32,620
photic bio system that's providing that

314
00:10:35,250 --> 00:10:33,480
kind of material

315
00:10:39,750 --> 00:10:35,260
but the ice is something we're

316
00:10:41,730 --> 00:10:39,760
interested in so 1977 they go down they

317
00:10:42,510 --> 00:10:41,740
find fish 500 kilometers from the open

318
00:10:44,519 --> 00:10:42,520
ocean it's kind of

319
00:10:48,329 --> 00:10:44,529
not a lot of food there for them what

320
00:10:49,680 --> 00:10:48,339
are they eating and then 2015 the wizard

321
00:10:51,389 --> 00:10:49,690
project they drilled at the grounding

322
00:10:52,769 --> 00:10:51,399
zone it was the first time they also

323
00:10:54,180 --> 00:10:52,779
found fish which was even more

324
00:10:56,550 --> 00:10:54,190
surprising so they were pretty shocked

325
00:10:58,380 --> 00:10:56,560
by that you would think that most things

326
00:11:00,000 --> 00:10:58,390
if it's currents that are carrying it in

327
00:11:01,199 --> 00:11:00,010
it'd be pretty pretty munched on by the

328
00:11:03,810 --> 00:11:01,209
time it got all the way back not a lot

329
00:11:06,630 --> 00:11:03,820
of carbon left for for larger kind of

330
00:11:08,160 --> 00:11:06,640
macro fauna and so we're trying to again

331
00:11:09,480 --> 00:11:08,170
break down that system so we're

332
00:11:11,370 --> 00:11:09,490
wondering is there sublation will input

333
00:11:12,660 --> 00:11:11,380
of we know there's a lot of sub glacial

334
00:11:14,130 --> 00:11:12,670
lakes subglacial hydrology that's the

335
00:11:16,860 --> 00:11:14,140
thing we've known about for just quite a

336
00:11:18,030 --> 00:11:16,870
decade now there's meltwater and active

337
00:11:22,079 --> 00:11:18,040
drainage underneath the N Arctic ice

338
00:11:23,940 --> 00:11:22,089
sheet are there methane seeps or vents

339
00:11:25,920 --> 00:11:23,950
hydrothermal or sub pet magazine systems

340
00:11:27,329 --> 00:11:25,930
in turn ether shelf that's been found at

341
00:11:29,220 --> 00:11:27,339
Larsen B after the Larsen B Ice Shelf

342
00:11:30,720 --> 00:11:29,230
collapse they went over the ship lot

343
00:11:32,370 --> 00:11:30,730
easier when there's no ice and they

344
00:11:33,600 --> 00:11:32,380
found just the whole sea floor was

345
00:11:36,180 --> 00:11:33,610
covered in microbial mats they were

346
00:11:37,829 --> 00:11:36,190
using methane is their carbon source and

347
00:11:39,480 --> 00:11:37,839
then of course the sort of the easiest

348
00:11:42,170 --> 00:11:39,490
one is over just it is enough it's

349
00:11:45,090 --> 00:11:42,180
enough carbon coming in from definition

350
00:11:47,790 --> 00:11:45,100
yeah so from the biological patience the

351
00:11:49,019 --> 00:11:47,800
physical controls exactly the same

352
00:11:50,460 --> 00:11:49,029
diagram but now we're gonna put some

353
00:11:52,079 --> 00:11:50,470
some data that we've collected on it

354
00:11:53,760 --> 00:11:52,089
what we're interested in this kind of

355
00:11:55,139 --> 00:11:53,770
this one two three four process where

356
00:11:56,550 --> 00:11:55,149
you have water that's moving around in

357
00:11:58,560 --> 00:11:56,560
the system and it's driving where ice is

358
00:11:59,940 --> 00:11:58,570
melting and accreted during apnea which

359
00:12:01,860 --> 00:11:59,950
is where you form CIF that's kind of

360
00:12:03,389 --> 00:12:01,870
this region here you're freezing out the

361
00:12:04,740 --> 00:12:03,399
freshwater component and rejecting the

362
00:12:07,019 --> 00:12:04,750
brine component that Brian makes the

363
00:12:08,639 --> 00:12:07,029
water more dense with water sinks the

364
00:12:10,800 --> 00:12:08,649
funny thing about pressure and water

365
00:12:12,269 --> 00:12:10,810
being such a weird compound is as you

366
00:12:13,769 --> 00:12:12,279
increase the pressure you decrease the

367
00:12:15,060 --> 00:12:13,779
freezing point and that's gonna be the

368
00:12:16,620 --> 00:12:15,070
most important thing driving this year

369
00:12:17,760 --> 00:12:16,630
so as you move water around and move it

370
00:12:21,389 --> 00:12:17,770
up and down on the water column

371
00:12:22,980 --> 00:12:21,399
you're gonna melt ice or make ice so

372
00:12:24,630 --> 00:12:22,990
what you do is you move this down and

373
00:12:26,519 --> 00:12:24,640
this is at the surface freezing point

374
00:12:28,920 --> 00:12:26,529
it's about negative two for most ocean

375
00:12:30,240 --> 00:12:28,930
water salinity as you move it down 500

376
00:12:31,650 --> 00:12:30,250
meters thousand meters also in the

377
00:12:33,750 --> 00:12:31,660
freezing point is about negative two and

378
00:12:34,980 --> 00:12:33,760
a half almost three degrees Celsius and

379
00:12:36,389 --> 00:12:34,990
that means that the wording you have is

380
00:12:39,389 --> 00:12:36,399
warm negative two degree weather

381
00:12:41,460 --> 00:12:39,399
relatively warm versus where you are so

382
00:12:43,230 --> 00:12:41,470
when that water influences or interacts

383
00:12:44,850 --> 00:12:43,240
with the bottom of the Shelf here where

384
00:12:46,260 --> 00:12:44,860
the freezing point is is much colder

385
00:12:48,000 --> 00:12:46,270
than that water it's actually melting

386
00:12:49,740 --> 00:12:48,010
the bottom of the shelf but then that

387
00:12:51,780 --> 00:12:49,750
moat water adds fresh water so you had

388
00:12:53,550 --> 00:12:51,790
really salt really salty dense water now

389
00:12:55,680 --> 00:12:53,560
you're adding fresh water that increases

390
00:12:57,510 --> 00:12:55,690
the density or excuse me reduces the

391
00:12:59,700 --> 00:12:57,520
and so now your water is floating back

392
00:13:01,020 --> 00:12:59,710
up this buoyant and starts to come back

393
00:13:01,980 --> 00:13:01,030
up the opposite happens with the

394
00:13:04,470 --> 00:13:01,990
freezing point and now all of a sudden

395
00:13:06,420 --> 00:13:04,480
that water is relatively colder than the

396
00:13:08,160 --> 00:13:06,430
than the depth that it's at and that

397
00:13:09,630 --> 00:13:08,170
makes it super cool and so if you have

398
00:13:10,920 --> 00:13:09,640
supercooled water you can start to to

399
00:13:12,150 --> 00:13:10,930
freeze ice it's like if you ever put

400
00:13:13,980 --> 00:13:12,160
distilled water in the freezer and take

401
00:13:18,420 --> 00:13:13,990
it out and not decided it that kind of

402
00:13:19,740 --> 00:13:18,430
thing and so we found that there's kind

403
00:13:21,630 --> 00:13:19,750
of a difference in patterns and you can

404
00:13:23,460 --> 00:13:21,640
observe these using the the conductivity

405
00:13:24,870 --> 00:13:23,470
and temperature temperature sensors that

406
00:13:27,000 --> 00:13:24,880
we have and you can draw these profiles

407
00:13:29,310 --> 00:13:27,010
and you can characterize the water based

408
00:13:31,410 --> 00:13:29,320
on the freezing point so the top here is

409
00:13:34,560 --> 00:13:31,420
is the the temperature of the water in

410
00:13:36,780 --> 00:13:34,570
Celsius so if you draw the freezing

411
00:13:38,760 --> 00:13:36,790
point here draw the temperature here you

412
00:13:40,260 --> 00:13:38,770
can pick out Oh ice shelf water that's

413
00:13:42,360 --> 00:13:40,270
this water that's coming up that's super

414
00:13:43,920 --> 00:13:42,370
cool that's below the freezing point or

415
00:13:45,960 --> 00:13:43,930
the high salinity shell border that

416
00:13:47,940 --> 00:13:45,970
supposed to be warmer on the right-hand

417
00:13:50,040 --> 00:13:47,950
side of the freezing point compared to

418
00:13:51,240 --> 00:13:50,050
compared to the isolation of water

419
00:13:53,820 --> 00:13:51,250
that's coming here from the surface from

420
00:13:55,440 --> 00:13:53,830
the polonium you can track that as you

421
00:13:56,940 --> 00:13:55,450
move back from the shelf and start to

422
00:13:59,120 --> 00:13:56,950
understand the water properties that are

423
00:14:01,440 --> 00:13:59,130
driving ice accretion and ice melt and

424
00:14:02,490 --> 00:14:01,450
then from there start to get at the

425
00:14:06,360 --> 00:14:02,500
processes that might be really relevant

426
00:14:08,010 --> 00:14:06,370
for ocean winds okay so this is one

427
00:14:09,720 --> 00:14:08,020
quick example of some stuff we can do I

428
00:14:11,040 --> 00:14:09,730
went ahead and put a video in a

429
00:14:12,960 --> 00:14:11,050
PowerPoint presentation which is always

430
00:14:15,120 --> 00:14:12,970
risky since you're working it's very

431
00:14:16,500 --> 00:14:15,130
simple basically this is a dive track

432
00:14:18,030 --> 00:14:16,510
where we're tracking the vehicles

433
00:14:19,950 --> 00:14:18,040
position as it goes underneath the ice

434
00:14:21,270 --> 00:14:19,960
and on top of that I can lay all kinds

435
00:14:22,500 --> 00:14:21,280
of data from the other sensors that we

436
00:14:24,750 --> 00:14:22,510
have but can look at trends in dissolved

437
00:14:26,670 --> 00:14:24,760
oxygen trends and dissolved organics

438
00:14:27,840 --> 00:14:26,680
friends and redox with pH and all kinds

439
00:14:29,550 --> 00:14:27,850
of things like that now from there start

440
00:14:31,560 --> 00:14:29,560
to make 3d maps of these environments

441
00:14:32,700 --> 00:14:31,570
which is a pretty good step ahead of the

442
00:14:35,700 --> 00:14:32,710
the one do you kind of mooring

443
00:14:37,890 --> 00:14:35,710
observations yeah so that's what I've

444
00:14:40,260 --> 00:14:37,900
got for today thank you very much I want

445
00:14:41,460 --> 00:14:40,270
to thank it's NASA sponsored work but

446
00:14:43,530 --> 00:14:41,470
there's no way that any of that happens

447
00:14:44,850 --> 00:14:43,540
without the NSF the United States and

448
00:14:47,250 --> 00:14:44,860
our program and our New Zealand

449
00:14:54,300 --> 00:14:47,260
collaborators thank you

450
00:15:09,740 --> 00:14:55,990
Thank You Justin

451
00:15:14,880 --> 00:15:12,960
as a good talk what do you envision for

452
00:15:17,220 --> 00:15:14,890
technology development for undersea

453
00:15:19,230 --> 00:15:17,230
communication on the skill of europa

454
00:15:21,120 --> 00:15:19,240
ocean yeah that's an excellent question

455
00:15:23,310 --> 00:15:21,130
I think that's kind of the biggest

456
00:15:24,870 --> 00:15:23,320
question right now in terms of this is

457
00:15:26,640 --> 00:15:24,880
obviously very long term thing you want

458
00:15:29,250 --> 00:15:26,650
to explore the ocean and ocean world or

459
00:15:31,380 --> 00:15:29,260
into the ocean of an ocean world that's

460
00:15:32,220 --> 00:15:31,390
like a 75 to 100 plus year kind of time

461
00:15:34,560 --> 00:15:32,230
scale in terms of the hardware

462
00:15:36,480 --> 00:15:34,570
development and the communication and

463
00:15:37,980 --> 00:15:36,490
the data relay from the ocean to the

464
00:15:39,810 --> 00:15:37,990
surface and trying to get through

465
00:15:41,100 --> 00:15:39,820
multiple kilometers of ice there's a

466
00:15:42,660 --> 00:15:41,110
crazy problem so people are working on

467
00:15:44,430 --> 00:15:42,670
that but it's not clear exactly what the

468
00:15:46,350 --> 00:15:44,440
best way to solve it is right now on

469
00:15:48,210 --> 00:15:46,360
earth is a little bit easier and we can

470
00:15:50,760 --> 00:15:48,220
do things with both optical and acoustic

471
00:15:52,140 --> 00:15:50,770
modems so optical data in water the

472
00:15:54,720 --> 00:15:52,150
water is very clear you can do it with

473
00:15:55,920 --> 00:15:54,730
pulsed lasers and get actually pretty

474
00:15:57,390 --> 00:15:55,930
good data rates but you're limited to

475
00:15:58,620 --> 00:15:57,400
just a couple hundred meters so not

476
00:16:01,890 --> 00:15:58,630
really good for the scales are looking

477
00:16:03,420 --> 00:16:01,900
at here acoustic you can do a bit better

478
00:16:04,769 --> 00:16:03,430
but of course your frequencies are

479
00:16:08,040 --> 00:16:04,779
different so your data rate is a little

480
00:16:10,200 --> 00:16:08,050
bit lower but you can get acoustic kind

481
00:16:12,270 --> 00:16:10,210
of through if you have like nodes that

482
00:16:13,770 --> 00:16:12,280
can amplify the signal as you go you can

483
00:16:15,300 --> 00:16:13,780
get a couple kilometers amplify a couple

484
00:16:16,770 --> 00:16:15,310
kilometers amplify of course it's

485
00:16:18,390 --> 00:16:16,780
dependent on the temperature and

486
00:16:19,590 --> 00:16:18,400
salinity you need to know the profile of

487
00:16:21,510 --> 00:16:19,600
the water column know your sounds to be

488
00:16:23,520 --> 00:16:21,520
very well so you need a little bit of

489
00:16:26,329 --> 00:16:23,530
data ahead of time to figure out how

490
00:16:28,140 --> 00:16:26,339
exactly to do that but one of the

491
00:16:29,670 --> 00:16:28,150
technologies that we actually use for

492
00:16:31,680 --> 00:16:29,680
localizing the robot underwater because

493
00:16:34,680 --> 00:16:31,690
you can't use GPS GPS makes it like this

494
00:16:36,320 --> 00:16:34,690
far through water or ice not great for

495
00:16:39,600 --> 00:16:36,330
the depths we're trying to get to is

496
00:16:41,370 --> 00:16:39,610
acoustic and long baseline transponders

497
00:16:43,860 --> 00:16:41,380
that you basically ping and use that to

498
00:16:45,329 --> 00:16:43,870
triangulate so yeah I think acoustic

499
00:16:47,490 --> 00:16:45,339
technology will really really be the way

500
00:16:49,230 --> 00:16:47,500
forward and probably some there's talk

501
00:16:51,390 --> 00:16:49,240
of like a robot that melts the ice off

502
00:16:52,680 --> 00:16:51,400
and drops off like well pucks behind it

503
00:16:55,199 --> 00:16:52,690
every couple kilometers that our

504
00:16:57,300 --> 00:16:55,209
acoustic modems and amplifiers to get

505
00:16:59,190 --> 00:16:57,310
data back is it'll be a one-way trip for

506
00:17:00,690 --> 00:16:59,200
the robot whenever you get an ocean roll

507
00:17:05,689 --> 00:17:00,700
but you need the data back it's a good

508
00:17:08,280 --> 00:17:05,699
question thank you hey Justin um so

509
00:17:10,980 --> 00:17:08,290
earlier you were telling me how you're

510
00:17:12,510 --> 00:17:10,990
about to go to another expedition to

511
00:17:15,780 --> 00:17:12,520
Antarctica you've been preparing for

512
00:17:18,000 --> 00:17:15,790
that so how's your strategy slightly

513
00:17:19,390 --> 00:17:18,010
different for that and what are some of

514
00:17:20,860 --> 00:17:19,400
your goals that might be

515
00:17:24,760 --> 00:17:20,870
and it's also it's different time of the

516
00:17:26,230 --> 00:17:24,770
year so yeah sure yeah so we generally

517
00:17:28,540 --> 00:17:26,240
when you go to an article you go in the

518
00:17:30,160 --> 00:17:28,550
summer which I guess it's a bit nicer

519
00:17:32,980 --> 00:17:30,170
and the Sun's up it's pretty easy work

520
00:17:35,140 --> 00:17:32,990
they actually 24-hour sunlight this year

521
00:17:36,370 --> 00:17:35,150
our work we're actually integrating a 4k

522
00:17:37,420 --> 00:17:36,380
camera system so we're pretty excited

523
00:17:40,150 --> 00:17:37,430
about that we're gonna get some really

524
00:17:41,680 --> 00:17:40,160
good imagery from the seafloor we did a

525
00:17:43,060 --> 00:17:41,690
couple of sites last year that we want

526
00:17:44,020 --> 00:17:43,070
to return to you underneath the Eric's

527
00:17:46,180 --> 00:17:44,030
place your tongue which is kind of a

528
00:17:47,470 --> 00:17:46,190
good your the miniature I shall do some

529
00:17:49,570 --> 00:17:47,480
practice work and get to the grounding

530
00:17:50,950 --> 00:17:49,580
side of that it's a it's a big ice

531
00:17:52,660 --> 00:17:50,960
stream that's coming off of the side of

532
00:17:54,610 --> 00:17:52,670
Erebus right next to base so we can

533
00:17:56,950 --> 00:17:54,620
drive there in the day kind of do day

534
00:17:58,390 --> 00:17:56,960
trips there and practice doing some of

535
00:18:00,190 --> 00:17:58,400
the acoustic observations and center

536
00:18:02,830 --> 00:18:00,200
observations that we want to do at the

537
00:18:04,660 --> 00:18:02,840
grounding line of the Ross we're excited

538
00:18:06,910 --> 00:18:04,670
about that that's we working on this

539
00:18:08,440 --> 00:18:06,920
year we've got some collaborators at

540
00:18:10,570 --> 00:18:08,450
tech that are building us some sensors

541
00:18:12,220 --> 00:18:10,580
we have a microfluidic system that's

542
00:18:14,320 --> 00:18:12,230
supposed to eventually hopefully measure

543
00:18:17,140 --> 00:18:14,330
cell counts in real time which is very

544
00:18:18,880 --> 00:18:17,150
interesting so that is that's an

545
00:18:22,030 --> 00:18:18,890
expeller and a couple other guys at a

546
00:18:23,560 --> 00:18:22,040
Stockman's lab jeez I think in chemistry

547
00:18:25,540 --> 00:18:23,570
but also has an engineering background

548
00:18:27,220 --> 00:18:25,550
and then we just got a postdoc Andy

549
00:18:29,110 --> 00:18:27,230
Mullen he's gonna be working on a

550
00:18:31,690 --> 00:18:29,120
digital holographic microscope which is

551
00:18:32,860 --> 00:18:31,700
over my head but basically my

552
00:18:35,860 --> 00:18:32,870
understanding is that is a way of

553
00:18:37,840 --> 00:18:35,870
measuring particle volumes kind of in 3d

554
00:18:39,790 --> 00:18:37,850
space as you're as you're transiting

555
00:18:41,560 --> 00:18:39,800
with the robot again in real time so

556
00:18:43,150 --> 00:18:41,570
some of that sensor development that

557
00:18:45,430 --> 00:18:43,160
we're pushing for future ocean world

558
00:18:47,680 --> 00:18:45,440
it's kind of like a Picasso Matisse cold

559
00:18:48,850 --> 00:18:47,690
tech sort of sort of thing we're excited

560
00:18:51,040 --> 00:18:48,860
about testing some of that stuff out

561
00:18:52,299 --> 00:18:51,050
this year as well wow that's very

562
00:18:54,760 --> 00:18:52,309
interesting thank you

563
00:19:02,710 --> 00:18:54,770
yeah thank you are there any more

564
00:19:08,259 --> 00:19:05,600
okay so a few questions first of all

565
00:19:10,519 --> 00:19:08,269
it's always lemon tree why not just use

566
00:19:14,180 --> 00:19:10,529
radar above the ice as opposed to

567
00:19:17,389 --> 00:19:14,190
attaching a sensor to the equipment for

568
00:19:19,639 --> 00:19:17,399
what question so we're trying to map the

569
00:19:22,820 --> 00:19:19,649
underneath the ice I guess China party

570
00:19:24,590 --> 00:19:22,830
yeah sure so it's a very good question

571
00:19:26,149 --> 00:19:24,600
one of the first projects that I worked

572
00:19:27,620 --> 00:19:26,159
on is called simple and that was an

573
00:19:29,090 --> 00:19:27,630
eight step project which you're probably

574
00:19:32,330 --> 00:19:29,100
familiar with Josh's work with Brittany

575
00:19:34,789 --> 00:19:32,340
a bit in the past and that was a don

576
00:19:36,259 --> 00:19:34,799
blankenship is the PI of reason which is

577
00:19:37,250 --> 00:19:36,269
the radar sensor on your upper clipper

578
00:19:40,639 --> 00:19:37,260
supposed to launch in the next five

579
00:19:42,200 --> 00:19:40,649
years if so hopefully and we designed

580
00:19:43,789 --> 00:19:42,210
that entire project or a large component

581
00:19:46,100 --> 00:19:43,799
of it to look at the ice from underneath

582
00:19:48,470 --> 00:19:46,110
to sort of ground truth the radar from

583
00:19:50,450 --> 00:19:48,480
above the radar works great until you

584
00:19:52,009 --> 00:19:50,460
introduce salt into the problem so you

585
00:19:53,330 --> 00:19:52,019
use the radar to kind of get structure

586
00:19:54,980 --> 00:19:53,340
of the ice and define the ice ocean

587
00:19:56,870 --> 00:19:54,990
interface but as soon as you hit any

588
00:19:58,669 --> 00:19:56,880
kind of conductive fluid or conductive

589
00:20:00,470 --> 00:19:58,679
material you lose all of the radar power

590
00:20:03,500 --> 00:20:00,480
and so you just kind of fade off into

591
00:20:06,379 --> 00:20:03,510
nothing so it's very hard to get like a

592
00:20:08,480 --> 00:20:06,389
unique solution for your radar if

593
00:20:09,259 --> 00:20:08,490
there's Brian in the situation so what

594
00:20:11,750 --> 00:20:09,269
we were doing with the underwater

595
00:20:13,850 --> 00:20:11,760
vehicles is basically mirroring the

596
00:20:15,980 --> 00:20:13,860
flight so the the reason instrument

597
00:20:17,870 --> 00:20:15,990
again also they use analog Antarctica as

598
00:20:20,180 --> 00:20:17,880
an analogue they would do over flights

599
00:20:21,680 --> 00:20:20,190
and get a radar profile of the ice in

600
00:20:23,419 --> 00:20:21,690
the ice shelf from above and then we

601
00:20:25,070 --> 00:20:23,429
kind of try to match that radar profile

602
00:20:27,259 --> 00:20:25,080
with the vehicle from underneath and

603
00:20:29,180 --> 00:20:27,269
these are so nice to look up and get the

604
00:20:31,220 --> 00:20:29,190
thickness and the concentrate or the

605
00:20:32,810 --> 00:20:31,230
composition and the overall texture of

606
00:20:34,430 --> 00:20:32,820
the ice cream below and use it as kind

607
00:20:36,379 --> 00:20:34,440
of like a ground truth for the radar and

608
00:20:37,759 --> 00:20:36,389
from there you can get some of the

609
00:20:39,680 --> 00:20:37,769
context and some of the information that

610
00:20:41,690 --> 00:20:39,690
you need to interview to interpret those

611
00:20:43,490 --> 00:20:41,700
radar results when you can't do that so

612
00:20:44,450 --> 00:20:43,500
one reason goes to Europa hopefully this

613
00:20:46,430 --> 00:20:44,460
work will give us a little bit better

614
00:20:48,289 --> 00:20:46,440
idea of how to interpret the bottom part

615
00:20:49,909 --> 00:20:48,299
of those measurements there but anyway

616
00:20:52,519 --> 00:20:49,919
I'm going to give us the thickness of

617
00:20:55,129 --> 00:20:52,529
the ice shelf is a good question cool

618
00:20:57,139 --> 00:20:55,139
thank you one of the question yeah so

619
00:20:58,970 --> 00:20:57,149
the picture you showed us underneath the

620
00:21:00,830 --> 00:20:58,980
ice at the interface you could see the

621
00:21:02,960 --> 00:21:00,840
sun shining - how deep you have to go

622
00:21:05,659 --> 00:21:02,970
and can you go that deep underneath this

623
00:21:07,549 --> 00:21:05,669
ice shell - you guys get away from the

624
00:21:10,159 --> 00:21:07,559
sunlight to try and see you know biology

625
00:21:12,320 --> 00:21:10,169
would be there without something that

626
00:21:14,149 --> 00:21:12,330
might be Don yeah so that photo was

627
00:21:14,480 --> 00:21:14,159
under sea ice which was probably about a

628
00:21:16,940 --> 00:21:14,490
meter

629
00:21:19,160 --> 00:21:16,950
ethic the ice shelf the McMurdo a shelf

630
00:21:20,600 --> 00:21:19,170
which is a smaller side section about 20

631
00:21:24,560 --> 00:21:20,610
meters thick and that's totally a photic

632
00:21:27,700 --> 00:21:24,570
you i'd say maybe upwards of 10 meters

633
00:21:29,720 --> 00:21:27,710
of ice normal kind of mostly fresh ice

634
00:21:31,900 --> 00:21:29,730
anything not thicker than that you don't

635
00:21:34,190 --> 00:21:31,910
have really much light left to drive

636
00:21:36,169 --> 00:21:34,200
photosynthesis the Ross Ice Shelf is

637
00:21:37,730 --> 00:21:36,179
anywhere from 300 meters to a thousand a

638
00:21:39,380 --> 00:21:37,740
thousand meters thick and it's not even

639
00:21:41,180 --> 00:21:39,390
the thickest in America it's large

640
00:21:45,770 --> 00:21:41,190
especially but the Amory Shelf is like

641
00:21:50,590 --> 00:21:45,780
upwards of kilometers day so yeah thank