EPOXI Team Develops New Method To Find Alien Ocean 42
Matt_dk writes "Astronomers have found more than 300 alien (extrasolar) worlds so far. Most of these are gas giants like Jupiter, and are either too hot (too close to their star) or too cold (too far away) to support life as we know it. Sometime in the near future, however, astronomers will probably find one that's just right — a planet with a solid surface that's the right distance for a temperature that allows liquid water — an essential ingredient in the recipe for life. Now scientists looking back at Earth with the Deep Impact/EPOXI mission have developed a method to indicate whether Earth-like extrasolar worlds have oceans."
Close giants... (Score:3, Informative)
-you get gravitational "wobble"
-you're more likely to be in line for a transit
-mass is enough for gravitational lensing
Re:Close giants... (Score:2, Informative)
Re:Water's nice, but ... (Score:2, Informative)
Well, yes, but finding gases in the atmosphere by spectroscopy is a lot easier. Luckily, they can look for two things. High-5's all round
Re:As We Know It (Score:3, Informative)
What makes you think they haven't thought of that? You're stating the obvious.
The reason they focus on 'life as we know it', is that /know how/ to search for 'life as we know it'.
By very definition, 'life as we don't know it' is more difficult to search for. How to you try to find something you don't know the characteristics of?
'Broader horizons' is one thing, but in a case we're trying to find extrasolar life, let's not invent artificial difficulties - it's already damn hard as it is.
Re:Gas giants (Score:5, Informative)
You raise a common question: why not look for life as we do not know it? Why are we looking for something so darn Earth-like?
Yes, life could exist elsewhere. There are soooo many possibilities. I mean, we seem pretty distance-from-the-star-centric, but even on Earth some critters aren't solar-energy dependent! Did you know Jupiter radiates more heat than it gets from the sun?
But basically, here's why we're looking for Earth-like planets:
Big gas giants are 0 for 4 on having life (that we know of)
Objects that do not revolve around a star: 0 for many
Small rocky planets: 1 for 4
Rocky Earth-sized planets that are 0.9-1.1 AU from a medium-sized star: 1 for 1
We have limited resources, so we are forced to narrow our scope. Narrowing our sights based on the few dozen studied objects in our solar system... it's easy to mock, but what else can we do? We can (1) keep searching through our own solar system to ameliorate some of the "sampling bias," and (2) look for rocky Earth-sized planets that are 0.9-1.1 AU from a medium-sized star. And that's pretty much what we're doing.