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[Music]

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so today this is an astrobiology

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conference I think Africanist anyone

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here as to the importance of looking for

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life outside of Earth be its within the

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solar system or beyond it so far we

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believe that our best possibility of

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finding life on another planet is in

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finding a doppelganger or edit earth a

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terrestrial planet around the same size

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as Earth and residing within its

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habitable zone which has been gone over

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many times today but in case you weren't

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listening is the zone where if there is

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water on the planet then it would be in

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its liquid state this is because a lot

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of our theories as to the necessary

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factors to support life include having

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access to liquid water now I'm going to

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apologize before I start I sometimes

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have a really hard time being habitable

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I don't know why but if I butcher it too

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many times I'm going to switch over to

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the liquid water zone instead but we'll

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see how I go all right so in a paper

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that we published last year dr. Steven

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Kane myself and all the other wonderful

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people that you see listed at the top

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here we catalog all the Kepler Hubble

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zoom exoplanets we use the data release

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24 q1 through 17 start a vetting process

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which we combined with the dr 25 jello

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properties table we from a dr 25 we took

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out the effective temperature of the

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star and the stellar radius and

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recalculated the radius of planets

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semi-major axes and the effectives or

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the flux that was received by the planet

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to create a more up-to-date data set we

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define four different parameters into

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which each planet cell and

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in turn gave us four different tables

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the first two parameters were to do with

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the hubble zone either the planet fell

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into the conservative habitable zone or

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the optimistic capital zone so this has

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already been gone over a fair bit today

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but for those who weren't here or we're

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not listening as again so the

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conservative boundary on the inner edge

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which was divine but copper up ooh in

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2014 as 0.99 au is the runaway

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greenhouse limit where the liquid oceans

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would evaporate on the outer edge we

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have at one point seven a you the

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maximum greenhouse effect where a co2

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greenhouse effect is at its maximum the

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optimistic boundary the inner edge is at

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0.75 au which we call the recent Venus

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limit which is based on observations

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that Venus may have had water on its

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surface around one gig year ago and the

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outer edge is at 1.8 au we called the

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early Mars limits which based on the

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empirical observations that Mars may

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have been habitable about 3.8 GB years

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ago so the second two are based on

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planet size because we all know size

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matters so the planets could either be

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within of the less than two rest

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Earth radii bracket or a ball radii so

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even though there is a growing consensus

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that the boundary between the

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terrestrial planets and the gaseous

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planet is around 1.6 Earth radii we

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chose to use two Earth radii to account

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for any uncertainties that came up in

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this della parameters that we're using

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and also the planetary parameters so we

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didn't want to inject any potentially

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terrestrial planets from

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tables so the four tables that we ended

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up with a table one at 20 with 20

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candidates sorry table 229 candidates

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table 363 candidates and table for with

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104

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candidates and each of these tables

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you'll find can be subsets of the others

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so table one which had our most

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stringent parameters is actually a

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subset of each of the other table so we

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can see much more clearly with this

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beautiful graphic which I've stolen from

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sunny harmon thank you sunny

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the have dual zone boundaries and we've

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seen Lee a couple iterations of this

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before today but in case you were asleep

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we'll go through it again as I go back

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okay so we have on the y-axis with

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increasing temperature of the staff you

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can see the change of the Hamill's and

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with the increase in temperature and on

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the bottom is not distance but there's

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still a flux and you can see f lines up

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with 100% so planets on the left-hand

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side of the graph are receiving more

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flux than the plants on the right-hand

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side

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and so the planets that are depicted

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here actually those depictions of the

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planets from our table - which is the

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less than two Earth radii in the

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optimistic capitalism so we plotted the

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histogram of the data set in the green

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we have our habitable zone candidates

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from Kepler and the grey is the entire

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Kepler catalog and we found that the

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distributions looked pretty much the

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same which was awesome and so we plotted

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a power law on each data set as you can

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see here we excluded the first two bins

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from our power laws due to lack of

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completeness or

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any planets less than 1.5 Earth radii so

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the power laws are not meant to

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represent complete list but just be a

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direct comparison of the entire Kepler

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catabolic versus the ones down in the

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Hubble's room so we saw that there was a

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very slight difference in the slope of

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each of the two datasets which implied

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that there was less we were less likely

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inside the smaller planets in the

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habitable zone but you need to remember

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also that planets in the habitable zone

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tend to be further away from their star

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and so we are less likely be able to see

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in them because their orbital period can

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mean that they don't transit the star

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often enough to be seen or confirmed and

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they're sometimes the orbital period can

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actually correspond with orbital period

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of Kepler spacecraft itself which

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increases the noise significantly so

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after doing the maximum likelihood

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estimator we found that there was no

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statistically significant difference

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between the two data sets which is

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excellent news because it means that we

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can use the distributions of any wide

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sample of planets and relate it to the

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distribution of the herald zone planets

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and considering the Hubble zoom planets

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are harder to find this will be really

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helpful in future statistical

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distributions or pebbles own one so our

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next steps the table that we've created

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have both confirmed and unconfident

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planets so validation of the unconfirmed

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planets is our next priority validation

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of category 1 and 2 candidates is

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actually underway as we at the moment

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using primarily adaptive optics and

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aslak

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with comparison of catalogs with

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estimate as Kepler's primary mission was

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to determine a to us we can use our

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catalog with the occurrence rate

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calculations of the Kepler mission and

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improving stellar parameters sir I'm

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clearing those parameters needs to be

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continued obviously our Hubble's own

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calculations of the story of the

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boundaries is needs what is reliant

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sorry I'm still the parameters so

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improving these stellar parameters is

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only going to be able to help us to

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refine our gallery or our catalog and

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lastly the category for candidates which

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this is my the most exciting bit for me

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was the amount of giant planets that we

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found in the optimistic habitable zone

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so royal giant planets themselves are

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not ideal candidates for finding life

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they do open the possibility of large

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terrestrial eggs or moons and so these

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moons expect this and famine yet but if

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they exist then they would also be in

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the Hubble zone and so could be great

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candidates for finding life out in the