How to tell if an extrasolar planet has oceans

[Bill Morris]

We don't really have the equipment for it yet, but once we have the Terrestrial Planet Finder or something like it to observe an extrasolar planet in the habitable zone of a star, continuous observation can reveal the presence of oceans if there are any, because brightness will vary depending on the phase of the planet if it has oceans, meaning light from a cresent will be reflecting more sunlight per area than full disc, for example, more so than with reflections off a rocky ball, gas giant, etc.

Here's an article that mentions such a method of detecting oceans:
http://www.physorg.com/news128257176.html

 

[TheMasterOfOrion]

As far as I remember Hubble found an extra solar planet with water back in 2007

but it was a "hot jupiter"
a term used to describe massive planet, with high gravity circling close to its parent star. Anyway the found water in it so that's a good start.

Although Hubble is great, it has its limits and isn't an ideal telescope for planet hunting

NASA's Kepler Mission launches in 2009. Kepler might improve on these hot Jupiter discoveries, designed distant Earth sized planets as they transit in front of their stars

The Europeans are planning something very ambitious called Darwin, a flotilla of Hubble sized telescopes flying in laser guided formation


Soon we might star classifying planets as M Class , Class H etc

 

[All Seeing Eye]

We don't really have the equipment for it yet, but once we have the Terrestrial Planet Finder

Last I heard it had been cancelled due to budget cuts.

 

[TheMasterOfOrion]

Last I heard it had been cancelled due to budget cuts.

NASA has given us scientific wonders but it is also a political monster and subject to the ebb and flow of political opinions (Nixon gutting Apollo). The next US election might be able to turn things around and put NASA back on Terrestrial Planet Finder route. Perhaps one of these creationist goons whispered sweet nothings into the ear of Bush 43 fearing NASA would discover alien life. McCain and Clinton don't seem to be too concerned with these creationist people and I think they would be more pro-NASA. Obama I'm not sure, he made some pro-NASA statements but also said stuff about cutting their budget.

 

[Jedi Marso]

With a TPF interferometer you could do a whole lot more than just find water- you could find chlorophyll and similar chemical compounds as well.

 

[Alpha_Geek]

I'm still gonna be an advocate of the "go and look" school of thought.

;-)

 

[Leandar]

NASA has given us scientific wonders but it is also a political monster and subject to the ebb and flow of political opinions (Nixon gutting Apollo). The next US election might be able to turn things around and put NASA back on Terrestrial Planet Finder route. Perhaps one of these creationist goons whispered sweet nothings into the ear of Bush 43 fearing NASA would discover alien life. McCain and Clinton don't seem to be too concerned with these creationist people and I think they would be more pro-NASA. Obama I'm not sure, he made some pro-NASA statements but also said stuff about cutting their budget.

This makes it sound like if you believe in creation, then you don't support NASA or possibly believe in alien life. I know plenty of people who believe in the Bible but nevertheless believe in the possibility of alien life. I should know, I'm one of them.

 

[James Bond]

NASA has given us scientific wonders but it is also a political monster and subject to the ebb and flow of political opinions (Nixon gutting Apollo). The next US election might be able to turn things around and put NASA back on Terrestrial Planet Finder route. Perhaps one of these creationist goons whispered sweet nothings into the ear of Bush 43 fearing NASA would discover alien life. McCain and Clinton don't seem to be too concerned with these creationist people and I think they would be more pro-NASA. Obama I'm not sure, he made some pro-NASA statements but also said stuff about cutting their budget.

This makes it sound like if you believe in creation, then you don't support NASA or possibly believe in alien life. I know plenty of people who believe in the Bible but nevertheless believe in the possibility of alien life. I should know, I'm one of them.

Same here, but I am NOT in any way, shape, or form a creationist.

 

[Mark Anthony]

I distinctly remember that during President Bush's Jan 14th 2004 New Space Vision speech (or there about) that "We may discover resources on the moon or Mars that will boggle the imagination, that will test our limits to dream". It's strange that comments such as this go largely unnoticed or there is a lack of motivation to probe further.

 

[Jadzia]

Would this be the visible effect with any liquid/amorphic surface -- not necessarily water?

 

[Bill Morris]

Sure, but the idea is to only look for this effect in the case of an Earth-sized planet found within a star's habitable zone, making a false positive unlikely. It requires extensive observation to pick up these changes in reflectivity and collect enough data to make that kind of judgment. Therefore, this would be limited to only the promising candidates found, since the same resources would be used to look for additional extrasolar planets instead. And, of course, all other data regarding such a planet would be taken into account.

 

[TheMasterOfOrion]

Kepler First Science Monday, 4th January 2010 http://www.starstryder.com/2010/01/04/kepler-first-science/

This is the morning of Kepler. I’m currently sitting in a the Marriot Ballroom watching the speaker, William J Borucki (NASA/Ames) gear up to announcing planets. This amazing mission has been imaging the same rich stellar field over and over looking for planetary transits: the slight dimming of light from a star that comes from an orbiting planet passing between us and that distance star. After 20 minutes of gearing up, he announced 5 new planets with orbital periods between 3.2 and 4.9 days orbiting stars larger than the sun at orbital distances 4.31 to 18.8 times the size of the Earth’s orbit. Because the stars are bigger than the Sun (by an amount not shown in the table), this is hard to quantify – they could be very near the stellar surfaces! – He referred to them as icy giants, but their surfaces are all hotter than 1500 Kelvin, with surfaces in 2 cases hotter than molten lead! These are large hot planets. 4 of these planets are all more massive than Jupiter, and one is smaller but still larger than Earth. There is a great table coming in a paper on Astro-PH going up later today (link to come) In addition to these stars, they have also discovered several neat variable stars: binaries, oscillating stars, pulsating variables, and more. This is one of the great things about this mission: While it was designed to find earth-sized planets orbiting other stars (given more time – they require data over more time than Jupiter-sized planets), it also collects data on variable stars in the field that is of amazing quality. This means that Kepler’s throw away data is somebody else’s science. Okay he just said something weird I’m going to have to look up. They have found small – Jupiter-ish sized in radius – that are hotter than the star they are orbiting. These look like tiny hot stars orbiting cooler stars BUT the hot object is too big to be a white dwarf and too hot to be anything else. He said there are more than one in the field and no one knows what they are. The Kepler Press conference is coming up soon, and hopefully we’ll get more info there.