Archive of Chat With Bill Borucki

[ Keli/NASAChatHost - 2 - 12:48:02 ]
You can post your questions for Bill here, but he will answer your questions via Real Media and Real Audio. Therefore, you will not see the answers to your questions here.

[ Keli/NASAChatHost - 4 - 13:32:26 ]
When posting your questions, please make sure they relate to the topic at hand. Bill will answer the best and most relevant questions "on the air" during his lecture as time permits. Other questions may be answered at the end of the lecture.

[ Keli/NASAChatHost - 5 - 13:35:06 ]
To access RealMedia and the lecture slides, return to http://quest.arc.nasa.gov/ltc/astrobio/index.html. You will probably want to bring up the slides in a new window--hold your mouse down on the slides link until a menu pops that allows you to do this.

[ Keli/NASAChatHost - 6 - 09:47:38 ]
You can find out more about Bill's work at http://www.kepler.arc.nasa.gov and http://web99.arc.nasa.gov

[ AstrobiologyExpert/Ames - 9 - 10:50:58 ]
RE: [AbelMendez] How do you define hab zones in more detail? Do they consider all the pressures and temp (of a water phase diagram) within a planet where there is liquid water or just average temp? What about a planet with polar liquid water?
Abel, There is much we don't know about how life forms and evolves. Until a few years ago we had no idea that vast amounts of life existed in rock thousands of feet below the surface. We didn't realize life could exist in pools of boiling water. Therefore we want to define the habitable zone very broadly. Any situation that could have liquid water should be investigated.

[ AbelMendez - 10 - 10:52:15 ]
Hi Bill. I might imagine a planet where there is liquid water at the poles but not at the equator (a least not regulary). Does the definition of hab zones includes this option?

[ Keli/NASAChatHost - 11 - 10:55:27 ]
Hi Abel, Bill Borucki is answering your questions. If you think of any more while he is answering, feel free to write more!

[ Keli/NASAChatHost - 12 - 10:57:00 ]
If you don't see your question posted immediately, don't worry--there is a small time delay.

[ AstrobiologyExpert/Ames - 14 - 10:58:46 ]
Hi Abel, Yes, it certainly would include such a situation. A more complex situation occurs for moons like Europa. The moon is too far from the Sun to have liquid water. However the heat generated in the planet by tidal forces from Jupiter are believed to cause ice to melt and form pools or oceans that lie beneath the ice. Could life exist there? Should objects that far away be considered to be in the "habitable zone"? We simply don't know. Science is fun because we get to search for such answers.

[ Keli/NASAChatHost - 15 - 11:02:29 ]
Thank you for coming today. We will be wrapping up soon, so we will take your last question if you like. Otherwise, I'd like to thank Bill for sharing his time and expertise with us today.

[ AbelMendez - 16 - 11:02:42 ]
How does the detection of ozone tells you about the amount of oxigen in the atmosphere?

[ Keli/NASAChatHost - 17 - 11:03:58 ]
If you'd like to attend future Astrobiology lectures this month, check out http://quest/ltc/astrobio/index.html for the schedule.

[ AstrobiologyExpert/Ames - 18 - 11:05:01 ]
RE: [AbelMendez] I know that Kasting is working with the hab zone definition. Could you mention other scientist working with this definition for extrasolar planets?
Hi Abel, Dave Black, Director of the Lunar and Planetary Institute, has often made the point that we need to think carefully about what we mean by "planet". He points out that the term planet should refer to an object formed by accrection of rocks and debris. Many of the extrasolar "planets" found by Doppler velocity techniques have very elliptical orbits which could indicate they were formed like stars, i.e., from density waves. Therefore he feels many of the latest discoveries don't fit the definition of a planet. Many other scientists feel that if it isn't self luminous then its a planet.

[ Keli/NASAChatHost - 19 - 11:05:10 ]
To learn more about the projects Bill spoke about in his lecture, visit http://www.kepler.arc.nasa.gov and http://web99.arc.nasa.gov

[ AstrobiologyExpert/Ames - 20 - 11:07:33 ]
Hi Abel, Ozone is formed from reactions of oxygen molecules and oxygen atoms. Therefore its presence is a good indicator that there is oxygen in the atmosphere. Ozone is easy to find in the spectrum, oxygen is not.

[ Keli/NASAChatHost - 22 - 11:09:57 ]
Before you leave, please help us out with your comments ut his chat at http://quest.arc.nasa.gov/qchats/qchat-surveys

[ Keli/NASAChatHost - 23 - 11:11:34 ]
Bill has agreed to stay on for another 10 minutes (until 11:20). Thank you Bill!

[ AbelMendez - 25 - 11:13:55 ]
Thank you Bill for your answers. Abel.

[ BillatAmes - 26 - 11:14:29 ]
RE: [AbelMendez] I'm doing research trying to define Life Zones starting by and assesment of the extremophiles. So far, they seem to be in a limited PT-space of a water phase diagram. Any suggestion?
Hi Abel, Since proteins are strongly affected by pH, it would be interesting to include it in your phase space.

[ BillatAmes - 27 - 11:20:15 ]
RE: [AbelMendez] It is possible to accurately estimate the amount of oxigen from the amount of ozone for an extrasolar planet? Is there is the possibility of an ozone-only atmosphere?
Hi Abel, No, the ozone level quickly rises to a substantial value and then stays nearly constant while the oxygen level increases from very low levels to levels hundreds of times larger. Ozone is very unstable and reacts to form the more stable molecules of oxygen. Generally ozone is formed when UV light strikes oxygen molecules. Hence the amount of ozone is often directly related to the intensity of the UV light rather than the number of oxygen molecules.

[ Keli/NASAChatHost - 28 - 11:22:01 ]
Thanks to Bill Borucki for his lecture and for taking the time to answer questions! Join us next week at 10 am Pacific Standard Time to hear Dave DesMarais talk about "How have the Earth and its biosphere influenced each other over time?"