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- [Sue] Okay, great, so this is VERITAS,

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Venus Emissivity, Radio
Science, InSAR, Topography,

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& Spectroscopy,

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and one of our key science questions is

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what makes a rocky planet habitable?

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Venus may well have been
the first habitable planet

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in our solar system,

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and we think it started
with all the building blocks

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of a habitable world.

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Clearly it's lost that habitability today,

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so we wanna understand the processes

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that led it down that path.

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So, in terms of our science
goals, we have three key goals.

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What processes shape
rocky planet evolution?

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What geological processes are active?

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And what's the evidence for
past and present interior water?

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So in terms of shaping
rocky planet evolution

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we look at global composition,
for the first time.

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We look at past geologic regimes.

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We answer the question for Venus,

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has the vulcanism been
steady, more like Earth,

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or was there some kind of catastrophe?

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And we also look at subduction,

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which is the first step in
charting plate tectonics.

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We think it may be active underneath today

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and this is a super important
question for predicting

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the conditions that may have
led to habitability on Earth.

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We'll look for a variety
of geological processes

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active today, vulcanism,
tectonic accretion.

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We also look at geochemical
weathering processes.

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And in terms of past and present water,

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one of the key things we
do is plot a global survey

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of plateaus that are thought
to be like Earth's continents,

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which formed when basalts melt

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over the presence of water on the Earth.

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So we're trying to
understand did these plateaus

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form in a similar way on Venus,

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and what does that say
about the history of water.

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And we're also gonna look for

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volcanic out-gassing water today.

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Is there interior water in Venus?

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From argon data that we have currently

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there is an implication that there may be

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more water in the interior
than even on Earth today.

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So the instrumentation, we
have just two instruments

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and gravity science.

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We have an interferometric radar,

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and this basically will
provide global topography

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292 higher resolution than
currently available data,

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which is approaching 30 years old now.

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It has a very high resolution

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and we have also 30 meter SAR imaging,

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globally and targeted
high resolution imaging

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and definition maps.

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We have the spectrometer.

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Of course, it's difficult
to do spectroscopy

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on the surface of Venus so
we'll set down a spectrometer

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with a very high
signal-to-noise to be able to

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get at the question of iron
variations across the surface.

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Do we have things that are
like basalt and like granite

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on the surface?

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We'll also look at surface weathering.

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Right now we have no idea really

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what the core size of Venus is.

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We'll have a much better gravity field

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from which we can derive the core size

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as well as get estimates
of elastic thickness.

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(indistinct murmuring)

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Okay, so, let me just take a cue from

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your past or present

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membership publication,
Vicki Meadows, and Barnes,

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to make this point about

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why geodynamics is so
important for exoplanets.

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This key shows what may be
observable in exoplanets,

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what's likely to require interpretation,

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such as observations, in green,

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and then definitely
requires modeling in orange.

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So VERITAS is really focused

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on the interior and the surface,

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and these are areas which
will always require modeling,

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very likely always require interpretation,

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and so we have this cosmic
accident, Venus and Earth,

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and we can't use our models to predict

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the differences between these two planets

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and how they evolved so differently.

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So it's gonna be very challenging

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to fully understand how exoplanets
come to be like they are

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from our observations that
are far more limiting.

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So we have a huge
opportunity to understand

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what's going on with these
two twin rocky planets.

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The only bodies that are likely to have

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these key processes, many
of which are active today.

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So, again, taken from
exoplanet literature,

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these are some of the factors
that may impact habitability.

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Oceans on the surface,

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and we investigate this with
the plateau composition,

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that, if more like granite on the Earth,

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they require past water.

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We look for current out-gassing,

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what's going on in the
secondary atmosphere today.

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We look for volcanism
and tectonic activity,

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weathering processes that help replenish

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atmospheric composition.

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We look for present-past
tectonism, volcanism.

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We look at surface
composition, weathering.

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And from the gravity field we can estimate

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the amount of heat coming
out of the interior

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which is related to elastic thickness.

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We'll get the first ever estimate
of a core size and state.

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We want to understand why Venus

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does not have a magnetic field today.

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Was it likely to have had one in the past?

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And, yeah, we developed all
these processes to interplay,

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and I suspect my time is
up, so I'll end it there.