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good afternoon and welcome to the

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science portion of today's briefings

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about nasa's new mission to study the

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sky

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of our near celestial neighbor the moon

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the mission is called the lunar

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atmosphere and dust environment explorer

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or laddie

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i'm rachel hoover in the public affairs

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office at nasa's ames research center in

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moffett field california where the

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mission was designed tested integrated

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and will be managed after launch

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earlier today we heard from lady team

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members about the spacecraft design

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it's right into space and the conditions

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leading up to tomorrow night's launch at

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11 27 pm eastern

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right here from nasa's wab's flight

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facility in virginia

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now we'll turn our attention to the

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science goals of the mission and a lunar

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laser communications demonstration on

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board

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before i turn our attention to the panel

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i'd like to make a take a moment to

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point out that you can learn more about

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the mission by visiting us online at

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lady

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or by following us on social media

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including twitter at nasaladdy

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in a moment we'll hear brief

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presentations from our panel and then

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we'll open it up to questions here at

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nasa wallops from nasa field centers and

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participants joining us from the phone

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it is now my pleasure to introduce

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today's panel

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joining us today is sarah noble

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lady program scientist from nasa

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headquarters

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rick elfic

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lady project scientist at nasa ames

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research center

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and don cornwell the lunar laser

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communications demonstration mission

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manager from nasa's goddard space flight

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center in greenbelt maryland

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and with that i'd like to pass it over

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to our panel

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thanks rachel i'd like to give you guys

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a quick overview of the science of lady

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lady has two major science goals to

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understand the lunar atmosphere as well

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as the dust environment around the moon

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and i think sometimes we get a little

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surprised when we start talking about a

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lunar atmosphere because most of us were

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taught in school that the moon doesn't

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actually have an atmosphere

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it does but it's it's very very thin

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it's so thin that the individual

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molecules that make up the atmosphere

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never see each other they don't interact

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they don't collide

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this is something we call an exosphere

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yes

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the earth actually has an exosphere as

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well but in fact you have to go out past

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where the international space station

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orbits before you get to this condition

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where the molecules are so far apart

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they don't collide

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on the moon that actually happens right

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at the surface so the term we use for

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this class of atmosphere is a surface

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boundary exosphere

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and in fact the moon is not the only

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example we have mercury

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a lot of the moons of outer planets

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as well as some of the larger asteroids

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in our in our solar system all have

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surface boundary exospheres it turns out

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to be the most common class of

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atmosphere we have and yet it's one that

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we don't really know very much about so

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ladies a really great opportunity to go

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to learn not only about the moon but

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about

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many many of the bodies in our solar

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system

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it's also a really good time for us to

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go and be

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working this mission uh the moon because

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the exosphere of the moon is so thin and

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so delicate it's easily disturbed by

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things like spacecraft landings and

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then this the moon has been pretty quiet

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lately in terms of landings we haven't

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landed anything there for a few decades

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but that's going to change there are a

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number of countries and even some

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private companies

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who are looking to land things on the

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moon in the upcoming years and so now is

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a really good time while the moon's

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atmosphere is still sort of pristine in

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its natural state for us to go and learn

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about it before we go and and impact it

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uh the d in latin stands for dust our

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other our other major science goals to

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understand the dust environment if i can

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get the second visual

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we've actually had questions about the

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dust environment on the moon since even

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before apollo uh on the on the left here

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you can see some images from the

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surveyor spacecraft which saw this

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strange thing on the horizon just before

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sunrise this sort of glow

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and we think that that actually might be

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due to dust getting lofted into the

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atmosphere and reflecting the light

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the apollo astronauts also saw saw this

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horizon glow on the left on the right

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there is a is a

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sketch from gene cernan's notebook

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apollo 17 astronaut who not only saw

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that horizon glow he saw these things

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that he called streamers going up high

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into the atmosphere tens of kilometers

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which we also think is due to the dust

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so we have three instruments on lady if

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we have three instruments on lady in

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which to look at

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our two science goals there is a lunar

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dust experiment

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designed and built by the university of

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colorado

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which will look at individual dust

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grains in situ

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there's a neutral mass spectrometer nms

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designed and built at nasa goddard space

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flight center which will look at the

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atmosphere

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and finally there's a uv spectrometer

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not the first spectrometer we've sent to

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the moon we've sent many spectrometers

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there but generally when you send a

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spectrometer it's looking down at the

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surface to look at the the minerals that

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make up the moon itself we'll actually

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be looking sideways through the

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atmosphere in the dust to understand

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what's going on just above the surface

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so that's a quick look at our science

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payload but i'm going to turn it over to

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rick now so he can give you a more

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in-depth view

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well as sarah just told you the the lady

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mission is about it's a tale of two

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mysteries the first being the thin

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tenuous very exotic lunar atmosphere

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utterly unlike our own and the second

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being this mysterious lofted substance

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purportedly dust that the apollo

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astronauts saw above the surface

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and so

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in the first video i'll show you it kind

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of illustrates uh the second mystery

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there's lady in orbit around the moon

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and the sun going down over the horizon

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and you can see this glow

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behind the spacecraft and that's meant

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to represent this possible dust cloud

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that exists around the moon near the

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terminator of the moon near the dark

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sunlit portion so those are the things

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that

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lady is equipped to look aft look at and

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try to explain and this next video shows

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you ladie pure wedding in space and i

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want to use this video to kind of

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illustrate the different instruments and

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their locations on the spacecraft so

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coming up actually is don cornell's

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instrument the laser com instrument on

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the side but if you look at the very top

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of the spacecraft the small tube looking

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outward is the ultraviolet invisible

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spectrometer the

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neutral mass spectrometer is down on the

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mid deck

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side of the spacecraft and the lunar

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dust experiment is at the top above the

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neutral mass spectrometer it's the sort

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of coffee can size thing that you saw at

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the top there so those are the three

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instruments that are meant to to

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address these

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two mysterious questions and i'd like to

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tell you a little bit about how one of

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those instruments is actually going to

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operate so the next video illustrates

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how the lunar dust experiment actually

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captures dust and analyzes it on its

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path around the moon

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basically it'll it will intersect and

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analyze any particles that are in its

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way as lady moves at 1.6 kilometers per

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second around the moon these particles

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come in and create little charges that

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are then registered on a detector and

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the size of those charges actually

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corresponds to the sizes of the grains

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that are being impacted the neutral mass

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spectrometer operates in a very similar

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fashion but it has a smaller aperture

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and it's really aimed at looking for the

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gas particles the atoms and the

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molecules in the tenuous lunar

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atmosphere and it identifies those

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molecules on the basis of their mass so

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you can identify things like calcium and

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titanium and iron that may be in present

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in the lunar atmosphere but we haven't

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measured them yet we don't know if

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they're really there or not the final

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video i wanted to show you folks is

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actually takes us back to 2009 and the l

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cross mission so this mission uh

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involved taking a a a an empty centaur

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space sorry launch vehicle

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and

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impacting it into the south pole of the

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moon into a location of permanent shadow

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and ultra ultra cold in places like that

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where there's no sunlight it gets so

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cold that ice if you can put it there

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will last for billions of years without

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going away and l cross was meant to to

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check out whether or not that actually

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occurs we had hints from lunar

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prospector but it wasn't until el cross

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actually impacted the surface that we

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could actually see ice lofted up into

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sunlight and uh the ultra the infrared

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spectrometer aboard l cross

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actually measured the the features of

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the ice that was present there so now we

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know there's ice there but how did it

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get there that's the question

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and so you can imagine a number of

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scenarios that would deliver ice to the

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cold regions of the moon one might be a

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cometary impact but there's another

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possibility that slowly over the

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millennia

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molecule by molecule water molecules

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have migrated hopping across the surface

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of the moon and finally some of them get

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cold trapped in these locations where

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there's no sunlight at all and and it's

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ultra ultra cold and they're stuck for

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basically forever

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ladies in a perfect position to look at

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those at the possibility of water and

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hydroxyl oh in the lunar atmosphere and

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so we'll be able to check that pathway

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that water cycle if you will that takes

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the possible water from the

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mid-latitudes up into the cold traps

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and the fourth instrument

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on the on the spacecraft is the lunar

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laser communications system a whole new

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way of doing business in terms of

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communications from deep space and don

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cornwall will tell you about that next

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thank you rick i'd also like to take

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this time to uh to thank the nasa

281
00:09:36,470 --> 00:09:34,640
science mission directorate and the lady

282
00:09:37,670 --> 00:09:36,480
project for the ride to the moon that

283
00:09:39,990 --> 00:09:37,680
that we're going to have for our

284
00:09:41,990 --> 00:09:40,000
technology uh demonstration

285
00:09:43,750 --> 00:09:42,000
uh as rick said we're not actually a

286
00:09:45,750 --> 00:09:43,760
science instrument but we are the lunar

287
00:09:47,990 --> 00:09:45,760
laser communications demonstration we're

288
00:09:50,310 --> 00:09:48,000
going to demonstrate the first

289
00:09:53,269 --> 00:09:50,320
high-speed two-way laser communications

290
00:09:54,630 --> 00:09:53,279
uh really for nasa and uh from the moon

291
00:09:56,870 --> 00:09:54,640
back to the earth

292
00:09:58,870 --> 00:09:56,880
and just as a point of reference uh we

293
00:10:00,310 --> 00:09:58,880
are six times the bandwidth the amount

294
00:10:01,829 --> 00:10:00,320
of data that we can send back in a

295
00:10:03,269 --> 00:10:01,839
certain amount of time

296
00:10:04,949 --> 00:10:03,279
as compared to the the most

297
00:10:05,750 --> 00:10:04,959
state-of-the-art radio system that was

298
00:10:07,509 --> 00:10:05,760
sent

299
00:10:10,230 --> 00:10:07,519
to the moon on the lunar reconnaissance

300
00:10:12,949 --> 00:10:10,240
orbiter in 2009 and at the same time we

301
00:10:15,430 --> 00:10:12,959
use half the weight and 25 less power so

302
00:10:18,389 --> 00:10:15,440
we're more efficient

303
00:10:19,750 --> 00:10:18,399
my first slide actually uh is an

304
00:10:21,350 --> 00:10:19,760
excellent illustration of the mission

305
00:10:22,790 --> 00:10:21,360
concept it's very straightforward when

306
00:10:24,630 --> 00:10:22,800
you look at it there's our optical

307
00:10:26,949 --> 00:10:24,640
terminal on the side of lady and uh

308
00:10:28,230 --> 00:10:26,959
we're exchanging uh laser beams uh

309
00:10:29,990 --> 00:10:28,240
between the earth and the moon and

310
00:10:32,870 --> 00:10:30,000
there's data imparted on each of those

311
00:10:34,230 --> 00:10:32,880
laser beams in the form of of hundreds

312
00:10:35,430 --> 00:10:34,240
of millions of little pulses every

313
00:10:36,230 --> 00:10:35,440
second

314
00:10:38,310 --> 00:10:36,240
uh

315
00:10:39,590 --> 00:10:38,320
so the next slide please

316
00:10:41,190 --> 00:10:39,600
so why are we interested in laser

317
00:10:43,670 --> 00:10:41,200
communications so

318
00:10:45,110 --> 00:10:43,680
over the last 50 years radio has served

319
00:10:47,670 --> 00:10:45,120
nasa very well

320
00:10:49,030 --> 00:10:47,680
for uh for providing space

321
00:10:51,670 --> 00:10:49,040
communications

322
00:10:53,430 --> 00:10:51,680
but uh like everyone uh everyone else

323
00:10:55,590 --> 00:10:53,440
nasa has needs for faster download

324
00:10:57,750 --> 00:10:55,600
speeds

325
00:11:01,590 --> 00:10:57,760
to bring back our

326
00:11:03,829 --> 00:11:01,600
data video and images high speed uh

327
00:11:05,590 --> 00:11:03,839
high resolution images and and 3d high

328
00:11:07,829 --> 00:11:05,600
definition video from satellites that

329
00:11:09,590 --> 00:11:07,839
orbit the earth and probes going to the

330
00:11:11,030 --> 00:11:09,600
moon and beyond

331
00:11:12,470 --> 00:11:11,040
so

332
00:11:14,550 --> 00:11:12,480
light waves are much shorter in

333
00:11:16,389 --> 00:11:14,560
wavelength than radio waves which means

334
00:11:18,069 --> 00:11:16,399
that we can pack more bits of data into

335
00:11:19,910 --> 00:11:18,079
every second on a light beam and also

336
00:11:22,470 --> 00:11:19,920
use smaller transmitters and receivers

337
00:11:25,350 --> 00:11:22,480
and if you can play the animation please

338
00:11:27,829 --> 00:11:25,360
so for example uh the the antenna on the

339
00:11:29,750 --> 00:11:27,839
left is a radio antenna it's many many

340
00:11:31,509 --> 00:11:29,760
uh tens of feet across

341
00:11:33,430 --> 00:11:31,519
and the the uh

342
00:11:35,430 --> 00:11:33,440
on the right that the animation where

343
00:11:37,350 --> 00:11:35,440
you saw the ground terminal got smaller

344
00:11:39,030 --> 00:11:37,360
that's our new

345
00:11:40,949 --> 00:11:39,040
uh optical communications ground

346
00:11:42,870 --> 00:11:40,959
terminal it'll be based in white sands

347
00:11:44,310 --> 00:11:42,880
it again leverages the fact that light

348
00:11:45,350 --> 00:11:44,320
waves are shorter and so you can keep

349
00:11:47,670 --> 00:11:45,360
the beams

350
00:11:49,990 --> 00:11:47,680
more collimated more focused and deliver

351
00:11:51,269 --> 00:11:50,000
more energy at a distant point so we can

352
00:11:53,030 --> 00:11:51,279
get more bandwidth with optical

353
00:11:57,829 --> 00:11:53,040
communications using a smaller size and

354
00:12:01,829 --> 00:11:59,670
so we have an animation here

355
00:12:03,910 --> 00:12:01,839
that actually shows how our system will

356
00:12:06,629 --> 00:12:03,920
work we have three ground stations one

357
00:12:08,870 --> 00:12:06,639
is at nasa jpl it's actually a site that

358
00:12:10,949 --> 00:12:08,880
they have in california the european

359
00:12:11,910 --> 00:12:10,959
space agency has a site and mit has a

360
00:12:17,110 --> 00:12:11,920
site

361
00:12:19,509 --> 00:12:17,120
will scan for laddie around the moon and

362
00:12:21,430 --> 00:12:19,519
when laddie sees that it sends a pulse

363
00:12:23,190 --> 00:12:21,440
back i'm a little bit behind on this and

364
00:12:25,110 --> 00:12:23,200
then that

365
00:12:27,190 --> 00:12:25,120
causes the ground station to then lock

366
00:12:29,430 --> 00:12:27,200
its beam to the uplink to the downlink

367
00:12:31,670 --> 00:12:29,440
beam and then we start communicating and

368
00:12:33,829 --> 00:12:31,680
we can send up to 220 megabits per

369
00:12:37,430 --> 00:12:33,839
second of data on the uplink from the

370
00:12:39,430 --> 00:12:37,440
earth to the moon and then as much as

371
00:12:40,550 --> 00:12:39,440
megabits per second from the moon down

372
00:12:43,110 --> 00:12:40,560
to the earth

373
00:12:45,509 --> 00:12:43,120
and uh i'd like to again point out that

374
00:12:47,590 --> 00:12:45,519
mit lincoln laboratory designed built

375
00:12:49,509 --> 00:12:47,600
tested and delivered at both our flight

376
00:12:51,030 --> 00:12:49,519
terminal and our first ground terminal

377
00:12:52,389 --> 00:12:51,040
and that we are partnering partnering

378
00:12:54,069 --> 00:12:52,399
with nasa jpl

379
00:12:55,750 --> 00:12:54,079
and the european space agency for our

380
00:12:58,150 --> 00:12:55,760
other two ground terminals

381
00:12:59,670 --> 00:12:58,160
and uh with that uh

382
00:13:01,269 --> 00:12:59,680
i return the

383
00:13:03,269 --> 00:13:01,279
stage to rachel

384
00:13:04,949 --> 00:13:03,279
thank you panel we'll now open it up for

385
00:13:07,110 --> 00:13:04,959
questions here in the audience at nasa

386
00:13:09,190 --> 00:13:07,120
wallops if you'd have a question please

387
00:13:12,550 --> 00:13:09,200
raise your hand wait for mike's and

388
00:13:14,230 --> 00:13:12,560
state your name and affiliation

389
00:13:16,550 --> 00:13:14,240
yes i have a question about the laser

390
00:13:17,430 --> 00:13:16,560
communication system uh

391
00:13:20,629 --> 00:13:17,440
can

392
00:13:23,350 --> 00:13:20,639
if you increase the wattage does it make

393
00:13:25,990 --> 00:13:23,360
it better or is it just you only need

394
00:13:28,790 --> 00:13:26,000
that minimum wattage to make it at peak

395
00:13:30,790 --> 00:13:28,800
efficiency i mean is it like with

396
00:13:32,230 --> 00:13:30,800
regular radio the bigger the antenna the

397
00:13:34,389 --> 00:13:32,240
more the wattage

398
00:13:36,150 --> 00:13:34,399
the better the signal so that's a good

399
00:13:37,990 --> 00:13:36,160
question this is a certain design point

400
00:13:39,829 --> 00:13:38,000
so we worked with the resources that

401
00:13:41,269 --> 00:13:39,839
that we had available to us

402
00:13:43,350 --> 00:13:41,279
and and

403
00:13:44,870 --> 00:13:43,360
and uh one of our you know we have some

404
00:13:46,790 --> 00:13:44,880
limits in power we're at the moon and

405
00:13:48,389 --> 00:13:46,800
we're on a small spacecraft and so this

406
00:13:50,470 --> 00:13:48,399
is a design point that was chosen for

407
00:13:53,030 --> 00:13:50,480
the transmitter power if the transmitter

408
00:13:56,069 --> 00:13:53,040
power were larger you could

409
00:13:59,030 --> 00:13:56,079
in theory send a higher data rate or

410
00:14:00,870 --> 00:13:59,040
more bits per second because

411
00:14:02,389 --> 00:14:00,880
or over a longer distance as well that's

412
00:14:04,069 --> 00:14:02,399
right thanks for the help on the

413
00:14:05,750 --> 00:14:04,079
question yes

414
00:14:07,509 --> 00:14:05,760
our next question also comes here from

415
00:14:09,509 --> 00:14:07,519
nasa wallops if you could please state

416
00:14:10,949 --> 00:14:09,519
your name and your affiliation hi ken

417
00:14:13,430 --> 00:14:10,959
kramer universe today i have two

418
00:14:15,590 --> 00:14:13,440
questions please uh first for don can

419
00:14:17,509 --> 00:14:15,600
you tell us i think

420
00:14:19,829 --> 00:14:17,519
the length of your experiment is is

421
00:14:22,230 --> 00:14:19,839
restricted to 30 days or so after you

422
00:14:24,949 --> 00:14:22,240
get to orbit can you talk about uh why

423
00:14:26,790 --> 00:14:24,959
that is and um i believe also the

424
00:14:29,750 --> 00:14:26,800
spacecraft is going into an elliptical

425
00:14:32,949 --> 00:14:29,760
orbit why why is it elliptical not

426
00:14:36,710 --> 00:14:34,790
okay so uh

427
00:14:39,189 --> 00:14:36,720
30 days is what we believe is sufficient

428
00:14:41,750 --> 00:14:39,199
to do our demonstration and we are along

429
00:14:43,590 --> 00:14:41,760
for the ride it is a science mission and

430
00:14:45,269 --> 00:14:43,600
we can't deprive our science team here

431
00:14:46,790 --> 00:14:45,279
of answering their very important

432
00:14:48,550 --> 00:14:46,800
questions as well

433
00:14:50,550 --> 00:14:48,560
so we think we can do everything we need

434
00:14:52,550 --> 00:14:50,560
to do within the 30-day period and we

435
00:14:54,470 --> 00:14:52,560
have a follow-on mission uh called the

436
00:14:56,150 --> 00:14:54,480
laser communications relay demonstration

437
00:14:58,870 --> 00:14:56,160
that'll be launched in 2017. it's a

438
00:15:00,949 --> 00:14:58,880
funded mission again based on mit

439
00:15:03,509 --> 00:15:00,959
technology but will be built at nasa

440
00:15:05,030 --> 00:15:03,519
goddard and that will will be a duration

441
00:15:06,150 --> 00:15:05,040
of two to five years where we hope to

442
00:15:08,629 --> 00:15:06,160
really

443
00:15:10,230 --> 00:15:08,639
demonstrate long-term performance

444
00:15:12,470 --> 00:15:10,240
and i can take the question about the

445
00:15:14,150 --> 00:15:12,480
elliptical orbit

446
00:15:16,310 --> 00:15:14,160
even if you start off with a circular

447
00:15:18,470 --> 00:15:16,320
orbit at low altitudes where we want to

448
00:15:20,069 --> 00:15:18,480
operate it very very quickly gets

449
00:15:21,670 --> 00:15:20,079
perturbed into an eccentric or

450
00:15:23,670 --> 00:15:21,680
elliptical orbit

451
00:15:25,509 --> 00:15:23,680
and so it's just a question of managing

452
00:15:26,949 --> 00:15:25,519
those perturbations which are induced by

453
00:15:28,470 --> 00:15:26,959
the gravity field of the moon which is

454
00:15:31,189 --> 00:15:28,480
very irregular compared to that of

455
00:15:34,470 --> 00:15:31,199
earth's as we know from grail now

456
00:15:35,590 --> 00:15:34,480
so it's that which perturbs the orbit

457
00:15:37,590 --> 00:15:35,600
and that

458
00:15:40,710 --> 00:15:37,600
changed orbit is something we need to

459
00:15:42,790 --> 00:15:40,720
adjust periodically so every week or so

460
00:15:45,350 --> 00:15:42,800
we perform a burn to attempt to

461
00:15:47,829 --> 00:15:45,360
basically re-sort of circula circularize

462
00:15:49,829 --> 00:15:47,839
the orbit and maintain periapsis the

463
00:15:51,350 --> 00:15:49,839
point of closest approach high enough so

464
00:15:54,470 --> 00:15:51,360
that frankly we don't crash into the

465
00:15:56,949 --> 00:15:54,480
surface of the moon

466
00:15:59,590 --> 00:15:56,959
it's the gravity lumpy gravity field

467
00:16:01,189 --> 00:15:59,600
that causes our orbit to perturb

468
00:16:08,310 --> 00:16:01,199
science

469
00:16:10,389 --> 00:16:08,320
safely get with the spacecraft lower is

470
00:16:11,590 --> 00:16:10,399
better for lady lowers better because

471
00:16:13,189 --> 00:16:11,600
because we've got two instruments that

472
00:16:14,870 --> 00:16:13,199
make in-situ measurements one's going

473
00:16:17,030 --> 00:16:14,880
for the dust the other is going for

474
00:16:19,189 --> 00:16:17,040
actual in in situ

475
00:16:20,870 --> 00:16:19,199
gas species and so the lower you go the

476
00:16:22,629 --> 00:16:20,880
more there are the better your signal

477
00:16:24,389 --> 00:16:22,639
the more you learn but we'll be

478
00:16:25,590 --> 00:16:24,399
wandering around in altitudes as the

479
00:16:27,110 --> 00:16:25,600
orbit gets

480
00:16:29,110 --> 00:16:27,120
perturbed by the gravity field of the

481
00:16:31,350 --> 00:16:29,120
moon we'll always try to get back to the

482
00:16:33,990 --> 00:16:31,360
low altitudes again

483
00:16:36,069 --> 00:16:34,000
i hope that helps you

484
00:16:38,069 --> 00:16:36,079
joe papillardo with uh popular mechanics

485
00:16:39,110 --> 00:16:38,079
um i'm just wondering if there's any uh

486
00:16:40,629 --> 00:16:39,120
if you could describe some of the

487
00:16:42,550 --> 00:16:40,639
differences between the light and dark

488
00:16:43,829 --> 00:16:42,560
sides of the moon in terms of the x

489
00:16:46,389 --> 00:16:43,839
exosphere

490
00:16:47,990 --> 00:16:46,399
oh sure um actually we've got a resident

491
00:16:49,590 --> 00:16:48,000
expert in the audience who made

492
00:16:50,629 --> 00:16:49,600
measurements of that very thing back on

493
00:16:54,470 --> 00:16:50,639
apollo

494
00:16:56,629 --> 00:16:54,480
audience and and

495
00:16:59,189 --> 00:16:56,639
i hope i do justice to what what i found

496
00:17:02,870 --> 00:17:01,110
certain of the species

497
00:17:05,510 --> 00:17:02,880
can basically

498
00:17:07,350 --> 00:17:05,520
freeze out on the surface as you as the

499
00:17:09,270 --> 00:17:07,360
the night side as you probably know of

500
00:17:10,630 --> 00:17:09,280
the moon since it's not in sunlight and

501
00:17:12,949 --> 00:17:10,640
there's very little atmosphere to

502
00:17:14,630 --> 00:17:12,959
conduct heat or it can convect heat it

503
00:17:16,949 --> 00:17:14,640
gets very very cold it gets below 100

504
00:17:19,829 --> 00:17:16,959
kelvins on the night side just before

505
00:17:21,669 --> 00:17:19,839
dawn that's cold enough so that when an

506
00:17:24,150 --> 00:17:21,679
atom or a molecule comes down and

507
00:17:26,470 --> 00:17:24,160
interacts with the surface grain

508
00:17:28,150 --> 00:17:26,480
it basically chills down too and so it's

509
00:17:30,630 --> 00:17:28,160
resident's time that molecule's

510
00:17:33,190 --> 00:17:30,640
resonance time on that grain can become

511
00:17:34,789 --> 00:17:33,200
very very long before it hops off again

512
00:17:37,350 --> 00:17:34,799
and when it does hop off it doesn't go

513
00:17:39,350 --> 00:17:37,360
nearly as high so the atmosphere kind of

514
00:17:42,070 --> 00:17:39,360
collapses or parts of the atmosphere can

515
00:17:43,430 --> 00:17:42,080
actually collapse at night whereas on

516
00:17:44,950 --> 00:17:43,440
the day side it gets warm enough that

517
00:17:47,029 --> 00:17:44,960
these guys are hopping around i think

518
00:17:50,070 --> 00:17:47,039
someone described it as like bunnies

519
00:17:53,590 --> 00:17:51,430
that's a picture i won't be able to get

520
00:17:54,789 --> 00:17:53,600
out of my head very soon

521
00:17:56,150 --> 00:17:54,799
but

522
00:17:57,590 --> 00:17:56,160
that's basically what the molecules of

523
00:17:59,990 --> 00:17:57,600
the exosphere are doing they're hopping

524
00:18:02,070 --> 00:18:00,000
around but they're sticking time the

525
00:18:03,510 --> 00:18:02,080
residence time on surface grains is

526
00:18:05,029 --> 00:18:03,520
strongly controlled by the temperature

527
00:18:14,549 --> 00:18:05,039
and therefore there's a day to night

528
00:18:19,190 --> 00:18:17,430
hi just a question about the uh

529
00:18:22,390 --> 00:18:19,200
given that it's a

530
00:18:25,350 --> 00:18:22,400
highly rarified exosphere what rate of

531
00:18:27,590 --> 00:18:25,360
detection are you expecting for the uh

532
00:18:28,789 --> 00:18:27,600
for the dust and for the uh for the

533
00:18:30,789 --> 00:18:28,799
elements are you expecting that to be

534
00:18:33,110 --> 00:18:30,799
fairly continuous or just

535
00:18:35,029 --> 00:18:33,120
once every few seconds or what that's a

536
00:18:36,870 --> 00:18:35,039
that's a really good question um the

537
00:18:39,190 --> 00:18:36,880
density of the dust that we are we have

538
00:18:42,390 --> 00:18:39,200
in our requirements for measurement at

539
00:18:45,830 --> 00:18:42,400
about 50 kilometers altitude is a pretty

540
00:18:48,310 --> 00:18:45,840
small number it's like only 100 or so

541
00:18:50,630 --> 00:18:48,320
dust particles per cubic meter

542
00:18:54,310 --> 00:18:50,640
that's not much i mean that's

543
00:18:58,070 --> 00:18:55,190
so

544
00:19:00,549 --> 00:18:58,080
uh running through that however at 1.6

545
00:19:02,310 --> 00:19:00,559
km 1600 meters per second you can

546
00:19:05,430 --> 00:19:02,320
imagine smacking into those things with

547
00:19:07,510 --> 00:19:05,440
the with the aperture of ldx uh fairly

548
00:19:09,990 --> 00:19:07,520
frequently and so if the dust is there

549
00:19:12,390 --> 00:19:10,000
in that density we'll see at a few

550
00:19:14,950 --> 00:19:12,400
counts per minute uh possibly even

551
00:19:16,390 --> 00:19:14,960
higher rates just how much is there and

552
00:19:17,510 --> 00:19:16,400
if we don't see anything that says

553
00:19:19,110 --> 00:19:17,520
pretty much

554
00:19:21,270 --> 00:19:19,120
we can place a very

555
00:19:22,870 --> 00:19:21,280
stringent lower upper limit on on how

556
00:19:24,549 --> 00:19:22,880
much dust is actually there but we'll

557
00:19:27,029 --> 00:19:24,559
know right away as soon as we drop down

558
00:19:28,390 --> 00:19:27,039
to those low altitudes

559
00:19:29,430 --> 00:19:28,400
as far as oh and the other instruments

560
00:19:31,190 --> 00:19:29,440
for for

561
00:19:31,990 --> 00:19:31,200
dust detection

562
00:19:34,470 --> 00:19:32,000
um

563
00:19:36,549 --> 00:19:34,480
the ultraviolet invisible spectrometer

564
00:19:38,630 --> 00:19:36,559
can look at a distance and integrate

565
00:19:40,230 --> 00:19:38,640
over a fairly large column at whatever

566
00:19:42,870 --> 00:19:40,240
dust is there the challenge that they

567
00:19:44,789 --> 00:19:42,880
have is for some of their measurements

568
00:19:47,350 --> 00:19:44,799
they're looking against the coronal and

569
00:19:48,789 --> 00:19:47,360
zodiacal light of the sun if you're

570
00:19:50,549 --> 00:19:48,799
looking back across the limb of the moon

571
00:19:52,390 --> 00:19:50,559
you'll see not just the dust that's

572
00:19:54,470 --> 00:19:52,400
scattering light toward you

573
00:19:57,029 --> 00:19:54,480
but also the zodiacal light in the inner

574
00:19:59,029 --> 00:19:57,039
solar system plus the coronal

575
00:20:00,470 --> 00:19:59,039
structure as well so it's a challenge

576
00:20:04,549 --> 00:20:00,480
but they've shown they can do it so

577
00:20:08,470 --> 00:20:06,149
so this is more of a practical question

578
00:20:10,230 --> 00:20:08,480
with the laser communication um

579
00:20:16,470 --> 00:20:10,240
what's the cost difference between a

580
00:20:19,669 --> 00:20:17,270
well

581
00:20:21,909 --> 00:20:19,679
we did a lot of development here to

582
00:20:23,110 --> 00:20:21,919
to solve a lot of the

583
00:20:24,630 --> 00:20:23,120
issues that are

584
00:20:26,950 --> 00:20:24,640
you know part of doing this this

585
00:20:28,230 --> 00:20:26,960
complicated mission so

586
00:20:30,950 --> 00:20:28,240
um

587
00:20:32,950 --> 00:20:30,960
initially it's it's it's expensive but

588
00:20:34,789 --> 00:20:32,960
but as we build more and more copies we

589
00:20:36,710 --> 00:20:34,799
expect that cost to go down just like

590
00:20:39,029 --> 00:20:36,720
for any system so there's a lot of

591
00:20:47,990 --> 00:20:39,039
non-recurring engineering that happened

592
00:20:57,270 --> 00:20:50,470
perhaps we can talk offline yeah

593
00:21:02,870 --> 00:20:59,830
matthew oh is it on matthew franco's

594
00:21:05,590 --> 00:21:02,880
popular science um question two

595
00:21:08,470 --> 00:21:05,600
questions one is how much dispersion is

596
00:21:11,510 --> 00:21:08,480
there in the laser beam between moon and

597
00:21:13,029 --> 00:21:11,520
earth i know in lunar ranging

598
00:21:14,630 --> 00:21:13,039
missions there's a fair amount of

599
00:21:17,190 --> 00:21:14,640
dispersion

600
00:21:20,149 --> 00:21:17,200
how big is the does the station need to

601
00:21:22,950 --> 00:21:20,159
be to reliably pick up the laser on the

602
00:21:24,870 --> 00:21:22,960
earth end and vice versa okay so when

603
00:21:26,230 --> 00:21:24,880
you say dispersion i think you mean uh

604
00:21:27,990 --> 00:21:26,240
actually the spread of the beam that's

605
00:21:30,549 --> 00:21:28,000
right so to speak yeah so it starts out

606
00:21:33,029 --> 00:21:30,559
at four inches in diameter

607
00:21:34,630 --> 00:21:33,039
from the spacecraft telescope and by the

608
00:21:37,350 --> 00:21:34,640
time it gets to the earth it's about

609
00:21:39,190 --> 00:21:37,360
three and a half miles in diameter six

610
00:21:41,430 --> 00:21:39,200
kilometers

611
00:21:43,270 --> 00:21:41,440
so it's it's still large but at the same

612
00:21:44,870 --> 00:21:43,280
time it's a very small point when seen

613
00:21:46,549 --> 00:21:44,880
from the moon and one of the big

614
00:21:48,390 --> 00:21:46,559
challenges we have is keeping that

615
00:21:50,070 --> 00:21:48,400
pointed accurately

616
00:21:53,190 --> 00:21:50,080
over the entire time you're trying to

617
00:21:56,870 --> 00:21:55,510
and the the second question was about

618
00:21:59,270 --> 00:21:56,880
the dust

619
00:22:01,350 --> 00:21:59,280
detection device and i'm not sure which

620
00:22:04,310 --> 00:22:01,360
of the two of you it should be directed

621
00:22:07,110 --> 00:22:04,320
to but uh you you mentioned that the

622
00:22:09,430 --> 00:22:07,120
size of the grain was correlated with

623
00:22:10,830 --> 00:22:09,440
the electric charge on it

624
00:22:13,909 --> 00:22:10,840
um

625
00:22:15,430 --> 00:22:13,919
so is that you want me to tell you a

626
00:22:17,190 --> 00:22:15,440
little more about yes if you would

627
00:22:20,149 --> 00:22:17,200
please

628
00:22:22,549 --> 00:22:20,159
actually as when the grains come in

629
00:22:24,070 --> 00:22:22,559
they uh they impact that witness plate

630
00:22:26,230 --> 00:22:24,080
at the back end of the instrument and

631
00:22:27,990 --> 00:22:26,240
they create a little plasma cloud and

632
00:22:30,789 --> 00:22:28,000
the amount of charge that's created by

633
00:22:32,950 --> 00:22:30,799
that is controlled by two mostly by two

634
00:22:34,310 --> 00:22:32,960
really important factors one is mass and

635
00:22:37,190 --> 00:22:34,320
the other is the velocity at which it

636
00:22:39,270 --> 00:22:37,200
comes in there are various

637
00:22:40,710 --> 00:22:39,280
formulae that relate those two things

638
00:22:42,310 --> 00:22:40,720
but we know what the velocity of the

639
00:22:44,470 --> 00:22:42,320
spacecraft is so that

640
00:22:46,070 --> 00:22:44,480
particular issue is taken care of in

641
00:22:48,070 --> 00:22:46,080
that way that way you can look at the

642
00:22:52,470 --> 00:22:48,080
charge and relate it directly to the

643
00:22:56,310 --> 00:22:55,029
hi john pritchard a nasa social

644
00:22:57,830 --> 00:22:56,320
participant

645
00:22:59,909 --> 00:22:57,840
um

646
00:23:02,549 --> 00:22:59,919
with the lady science with the study of

647
00:23:04,070 --> 00:23:02,559
the exosphere and the scientific results

648
00:23:05,750 --> 00:23:04,080
that come out of that

649
00:23:08,470 --> 00:23:05,760
i think we're looking at

650
00:23:11,029 --> 00:23:08,480
evolution of the earth moon system and

651
00:23:12,870 --> 00:23:11,039
then getting into some earth science

652
00:23:14,789 --> 00:23:12,880
so what

653
00:23:17,510 --> 00:23:14,799
can we point to in earth science that we

654
00:23:18,789 --> 00:23:17,520
could learn about in future from

655
00:23:20,950 --> 00:23:18,799
this work

656
00:23:27,750 --> 00:23:20,960
for example is it possible to learn

657
00:23:27,760 --> 00:23:31,190
okay

658
00:23:34,630 --> 00:23:33,029
i'm not sure i follow where you're going

659
00:23:36,310 --> 00:23:34,640
with that question we've measured the

660
00:23:38,630 --> 00:23:36,320
terrestrial magnetic field multiple

661
00:23:40,070 --> 00:23:38,640
times with very very high precision

662
00:23:41,990 --> 00:23:40,080
dynamics

663
00:23:43,510 --> 00:23:42,000
and maintenance okay well

664
00:23:45,190 --> 00:23:43,520
okay but the earth and the moon have

665
00:23:47,430 --> 00:23:45,200
evolved down two very very different

666
00:23:48,789 --> 00:23:47,440
paths since their birth together you

667
00:23:51,269 --> 00:23:48,799
know roughly four and a half billion

668
00:23:53,750 --> 00:23:51,279
years ago the earth is retained and

669
00:23:55,350 --> 00:23:53,760
accumulated more volatiles hence oceans

670
00:23:57,990 --> 00:23:55,360
and things like that and that is that

671
00:23:59,190 --> 00:23:58,000
along with its very very active geologic

672
00:24:00,950 --> 00:23:59,200
processes

673
00:24:02,070 --> 00:24:00,960
have really sculpted and changed the

674
00:24:03,430 --> 00:24:02,080
surface of the earth we've got

675
00:24:05,669 --> 00:24:03,440
continents that drift around because the

676
00:24:07,750 --> 00:24:05,679
mantle is convecting there's an interior

677
00:24:09,269 --> 00:24:07,760
dynamo that gives rise to the magnetic

678
00:24:11,110 --> 00:24:09,279
field that

679
00:24:13,990 --> 00:24:11,120
constantly change the surface of the

680
00:24:16,470 --> 00:24:14,000
earth the moon on the other hand has one

681
00:24:18,310 --> 00:24:16,480
geologic process going on today and one

682
00:24:20,149 --> 00:24:18,320
only and that's impact

683
00:24:21,750 --> 00:24:20,159
asteroids come in and they smack into

684
00:24:24,310 --> 00:24:21,760
the surface of the moon and they create

685
00:24:26,230 --> 00:24:24,320
craters so material is excavated and

686
00:24:27,990 --> 00:24:26,240
redistributed around

687
00:24:30,950 --> 00:24:28,000
but you know they're they're really

688
00:24:32,390 --> 00:24:30,960
different worlds fortunately for us

689
00:24:35,190 --> 00:24:32,400
unfortunately for the russians you know

690
00:24:36,710 --> 00:24:35,200
the the uh impacts don't occur very

691
00:24:38,070 --> 00:24:36,720
often on the earth

692
00:24:38,950 --> 00:24:38,080
they're happening all the time on the

693
00:24:41,110 --> 00:24:38,960
moon

694
00:24:43,029 --> 00:24:41,120
now that said there's one other aspect

695
00:24:45,510 --> 00:24:43,039
of this that's kind of interesting if

696
00:24:47,510 --> 00:24:45,520
the moon has maintained this this low

697
00:24:49,590 --> 00:24:47,520
obliquity this very low inclination the

698
00:24:51,029 --> 00:24:49,600
earth's inclination is 23.5 degrees

699
00:24:53,350 --> 00:24:51,039
that's why we have seasons the moon

700
00:24:55,990 --> 00:24:53,360
really doesn't have seasons it's a very

701
00:24:57,430 --> 00:24:56,000
stable system that means the locations

702
00:24:59,350 --> 00:24:57,440
that the boat at the north pole and the

703
00:25:01,269 --> 00:24:59,360
south pole some of those locations are

704
00:25:03,029 --> 00:25:01,279
in permanent shadow that also means that

705
00:25:05,510 --> 00:25:03,039
stuff that has been delivered to those

706
00:25:07,830 --> 00:25:05,520
locations from the earliest times of the

707
00:25:09,430 --> 00:25:07,840
solar system is still there

708
00:25:11,350 --> 00:25:09,440
that's stuff that was delivered to the

709
00:25:13,350 --> 00:25:11,360
earth in the earliest times of the solar

710
00:25:14,789 --> 00:25:13,360
system too but it's been lost the stuff

711
00:25:17,269 --> 00:25:14,799
that was delivered in the very earliest

712
00:25:19,110 --> 00:25:17,279
times has been lost by the same geologic

713
00:25:21,590 --> 00:25:19,120
process as i was just talking about the

714
00:25:23,669 --> 00:25:21,600
geology covers it up it's gone we can't

715
00:25:25,750 --> 00:25:23,679
recover it anymore the moon is still

716
00:25:28,070 --> 00:25:25,760
there it's still sequestered so if we go

717
00:25:29,990 --> 00:25:28,080
there to the poles of the moon and start

718
00:25:32,789 --> 00:25:30,000
digging this stuff up we might be

719
00:25:34,950 --> 00:25:32,799
looking at the prebiotic materials

720
00:25:38,390 --> 00:25:34,960
that gave rise to life on earth the same

721
00:25:42,710 --> 00:25:40,390
thank you we have time for a few more

722
00:25:44,789 --> 00:25:42,720
questions

723
00:25:46,149 --> 00:25:44,799
i have a real quick question and it

724
00:25:48,310 --> 00:25:46,159
involves

725
00:25:51,029 --> 00:25:48,320
what what do we know about the moon's

726
00:25:53,669 --> 00:25:51,039
outgassing and how does that tell us

727
00:25:56,710 --> 00:25:53,679
about the interior and its state of

728
00:26:01,669 --> 00:25:58,149
is it fair for jim green to ask

729
00:26:06,230 --> 00:26:04,070
we do know that argon 40 is out gassing

730
00:26:07,190 --> 00:26:06,240
from the interior of the moon that was

731
00:26:09,669 --> 00:26:07,200
the

732
00:26:11,510 --> 00:26:09,679
experimental results that dick hodges

733
00:26:14,950 --> 00:26:11,520
over there sitting in the audience got

734
00:26:15,669 --> 00:26:14,960
back in the 70s on apollo 17. argon 40

735
00:26:18,470 --> 00:26:15,679
is

736
00:26:21,029 --> 00:26:18,480
comes from radiogenic decay of potassium

737
00:26:22,070 --> 00:26:21,039
40 of which there is a fair amount on

738
00:26:24,230 --> 00:26:22,080
the moon

739
00:26:25,750 --> 00:26:24,240
we see it actually in distinct locations

740
00:26:27,510 --> 00:26:25,760
on the moon and that's really strongly

741
00:26:29,269 --> 00:26:27,520
related to the crystal history of the

742
00:26:30,149 --> 00:26:29,279
moon and the interior history of the

743
00:26:31,990 --> 00:26:30,159
moon

744
00:26:33,110 --> 00:26:32,000
another thing we observe that may some

745
00:26:34,390 --> 00:26:33,120
of which may be coming out of the

746
00:26:35,430 --> 00:26:34,400
interior and should be expected is

747
00:26:38,310 --> 00:26:35,440
helium

748
00:26:40,549 --> 00:26:38,320
but it looks like based on lro results

749
00:26:43,029 --> 00:26:40,559
that the helium that is seen in the

750
00:26:44,710 --> 00:26:43,039
lunar atmosphere mostly derives from the

751
00:26:46,630 --> 00:26:44,720
solar wind so that's something that's

752
00:26:47,750 --> 00:26:46,640
coming from the outside in

753
00:26:49,110 --> 00:26:47,760
now

754
00:26:50,470 --> 00:26:49,120
more about the interior of the moon

755
00:26:52,310 --> 00:26:50,480
there may be other things that are

756
00:26:53,590 --> 00:26:52,320
leaking out argon 40 gets out because

757
00:26:55,590 --> 00:26:53,600
it's a noble gas and it doesn't

758
00:26:58,470 --> 00:26:55,600
chemically react with anything

759
00:27:00,390 --> 00:26:58,480
other substances such as water may not

760
00:27:01,830 --> 00:27:00,400
be so lucky there may be juvenile water

761
00:27:03,510 --> 00:27:01,840
still in the interior of the moon in

762
00:27:05,110 --> 00:27:03,520
fact mineral samples have revealed the

763
00:27:07,830 --> 00:27:05,120
presence of water in those earliest

764
00:27:09,669 --> 00:27:07,840
minerals appetite grains

765
00:27:11,350 --> 00:27:09,679
and i'm getting way deep into the the

766
00:27:12,470 --> 00:27:11,360
science of that but the water probably

767
00:27:14,549 --> 00:27:12,480
would have a hard time getting out

768
00:27:16,950 --> 00:27:14,559
because it's so reactive so anything we

769
00:27:19,190 --> 00:27:16,960
see near this near or on the surface

770
00:27:21,590 --> 00:27:19,200
either was excavated delivered or

771
00:27:23,669 --> 00:27:21,600
migrated from low latitudes and got cold

772
00:27:25,350 --> 00:27:23,679
trap

773
00:27:27,909 --> 00:27:25,360
thank you we have time for one more

774
00:27:32,870 --> 00:27:27,919
question from social media or media here

775
00:27:32,880 --> 00:27:36,230
oh man

776
00:27:41,590 --> 00:27:38,389
if jim green can answer ask a question i

777
00:27:43,830 --> 00:27:41,600
guess i can too uh of course the apollo

778
00:27:45,750 --> 00:27:43,840
astronauts left lunar

779
00:27:47,110 --> 00:27:45,760
uh corner cubes

780
00:27:48,389 --> 00:27:47,120
reflectors on the surface of the moon

781
00:27:49,830 --> 00:27:48,399
and we've been pinging them with lasers

782
00:27:52,710 --> 00:27:49,840
for years to measure the earth moon

783
00:27:55,990 --> 00:27:54,230
the laser common principle also has

784
00:27:58,070 --> 00:27:56,000
arranged an instrument how much more

785
00:27:59,750 --> 00:27:58,080
accurate now of course ladies in orbit

786
00:28:02,149 --> 00:27:59,760
how much more accurate will the laser

787
00:28:04,149 --> 00:28:02,159
come give us a measurement of distance

788
00:28:08,149 --> 00:28:04,159
to at least lady

789
00:28:09,430 --> 00:28:08,159
then than the lunar reflectors

790
00:28:10,389 --> 00:28:09,440
well we're really good at measuring

791
00:28:12,310 --> 00:28:10,399
relative

792
00:28:14,070 --> 00:28:12,320
changes in the distance along the path

793
00:28:15,669 --> 00:28:14,080
and and we're working with some of the

794
00:28:18,070 --> 00:28:15,679
science folks

795
00:28:20,230 --> 00:28:18,080
at nasa to see if we can turn that into

796
00:28:21,909 --> 00:28:20,240
absolute range measurements but we know

797
00:28:23,990 --> 00:28:21,919
we can measure relative changes down to

798
00:28:26,389 --> 00:28:24,000
the centimeters and with a lot of

799
00:28:28,470 --> 00:28:26,399
averaging uh the variations in maybe

800
00:28:29,669 --> 00:28:28,480
microns per second even as what's been

801
00:28:31,110 --> 00:28:29,679
discussed

802
00:28:32,389 --> 00:28:31,120
so uh

803
00:28:33,510 --> 00:28:32,399
there are a lot of variables when you're

804
00:28:34,950 --> 00:28:33,520
actually doing the ranging you have to

805
00:28:36,710 --> 00:28:34,960
account for the atmosphere and what that

806
00:28:38,950 --> 00:28:36,720
does because sometimes the path like

807
00:28:41,350 --> 00:28:38,960
changes there and and so uh

808
00:28:43,029 --> 00:28:41,360
but as i said we're working with them to

809
00:28:44,470 --> 00:28:43,039
see what we can back out to be able to

810
00:28:49,110 --> 00:28:44,480
get absolute range measurements but

811
00:28:53,269 --> 00:28:51,029
we have time for one more question from

812
00:28:54,950 --> 00:28:53,279
a member of the social media team from

813
00:28:59,909 --> 00:28:54,960
headquarters news media here in the

814
00:29:04,789 --> 00:29:02,310
hi i'm miriam kramer i'm with space.com

815
00:29:05,990 --> 00:29:04,799
uh and i was just wondering

816
00:29:08,310 --> 00:29:06,000
uh

817
00:29:10,470 --> 00:29:08,320
are there engineering implications that

818
00:29:12,470 --> 00:29:10,480
could potentially come from the science

819
00:29:13,909 --> 00:29:12,480
of this mission for instance at

820
00:29:17,029 --> 00:29:13,919
something having to do with the lander

821
00:29:19,110 --> 00:29:17,039
or even probes to

822
00:29:28,149 --> 00:29:19,120
various asteroids or

823
00:29:32,070 --> 00:29:29,990
um if you're asking about what the

824
00:29:34,630 --> 00:29:32,080
science instruments can bring

825
00:29:36,950 --> 00:29:34,640
to future exploration well there are

826
00:29:38,230 --> 00:29:36,960
similar problems that other bodies we'd

827
00:29:40,310 --> 00:29:38,240
love to know

828
00:29:42,630 --> 00:29:40,320
whether loft of dust occurs at larger

829
00:29:44,230 --> 00:29:42,640
asteroids whether lofty dust occurs

830
00:29:46,549 --> 00:29:44,240
leaks expect that if it happens at the

831
00:29:48,549 --> 00:29:46,559
moon it happens elsewhere as well

832
00:29:50,389 --> 00:29:48,559
so sending similar instruments to those

833
00:29:51,510 --> 00:29:50,399
bodies will will confirm and further

834
00:29:54,310 --> 00:29:51,520
inform us

835
00:29:56,230 --> 00:29:54,320
uh of that physical process as exotic as

836
00:29:58,789 --> 00:29:56,240
it is

837
00:30:00,310 --> 00:29:58,799
so you can make second use of anything

838
00:30:01,590 --> 00:30:00,320
that you developed for space flight but

839
00:30:03,510 --> 00:30:01,600
i was wondering if you were going in a

840
00:30:04,470 --> 00:30:03,520
different direction with maybe the reuse

841
00:30:05,909 --> 00:30:04,480
of

842
00:30:11,110 --> 00:30:05,919
the lady

843
00:30:13,909 --> 00:30:13,110
okay all right thank you

844
00:30:16,230 --> 00:30:13,919
okay

845
00:30:18,230 --> 00:30:16,240
i'll stop there then

846
00:30:20,389 --> 00:30:18,240
thank you panel that concludes today's

847
00:30:21,830 --> 00:30:20,399
science briefing about the lady mission

848
00:30:25,590 --> 00:30:21,840
you can learn more about the mission by

849
00:30:27,430 --> 00:30:25,600
visiting us online at nasa.gov lady or

850
00:30:31,110 --> 00:30:27,440
by following the mission on our social

851
00:30:33,510 --> 00:30:31,120
media including twitter at nasaladdy and

852
00:30:35,430 --> 00:30:33,520
tune in tomorrow at 9 30 pm eastern when

853
00:30:36,549 --> 00:30:35,440
nasa tv begins its live mission

854
00:30:39,750 --> 00:30:36,559
broadcast

855
00:30:41,830 --> 00:30:39,760
and launch is scheduled for 11 27 pm