Kepler Finds Five More Exoplanets 102
Arvisp was one of several readers to send news of five new exoplanets discovered by the Kepler space telescope. In addition to the new "hot Jupiters" — the easiest targets to find — Kepler's early data has turned up some oddities, including something that is too hot to be a planet and too small to be a star. And one of the exoplanets is so fluffy that "it has the density of Styrofoam." The real news is that Kepler works as designed, and the scientists running it are fully confident that it will find Earth-like planets in some star's habitable zone, if they are out there to be found. Here is NASA's press release.
yay ! Science :) (Score:1, Insightful)
Yay a new planet :)
Re:But Why? (Score:5, Insightful)
Sure, finding habitable planets is cool. But what are they going to do once they've found one? Tick a box? Celebrate humanity?
Perform spectroscopy experiments to see if the planet has more in common with ours than just mass and relative distance from its star?
As part of the long, long process of answering one of the most amazing questions in humanity's existence: Are we alone in the universe? Is life unique to our planet, extremely rare, or as common as the stars themselves?
You might have you own theories one way or the other, but a theory isn't an answer. This is about evidence.
can think of two main reasons (Score:5, Insightful)
Obviously the reason it makes headlines is that the question of how many human-habitable planets there are, and what kinds of properties they have, is tied to the question of whether anything vaguely like earth-like life exists elsewhere in the universe.
However a good deal of astronomers are also just interested in everything about the cosmos: what's out there, how does it work, how does it relate to other things, what kinds of variations are there, etc. From that perspective, this particular kind of thing, "exoplanet", is a class of far-away object we don't have a lot of examples of and can't give particularly confident accounts of (how and how often they form, their distribution, etc.). Even if there was no tie-in to human habitability, there are a number of astronomers interested in collecting more data on and clarifying our understanding of basically any class of "thing we don't yet know everything about".
Re:What about what we don't know yet? (Score:5, Insightful)
> My point is that our definition of habitable is going to change dramatically
> as we get more information.
In the meantime, however, we must work with what we have. How likely are we to find anything interesting if we just look around randomly?
Re:Due diligence (Score:1, Insightful)
Time lord?
Re:But Why? (Score:3, Insightful)
If there are not many planets that show signs of possible life at all, then there are going to be very few where life has even possibly developed our kind of intelligence. There would be even fewer where there might be a technological civilization. Looking for a signal or sending one becomes a real needle in a haystack operation. If we could afford to send just a few signals, say by high powered laser, there would still be no point in funding it, because we would still need to send those signals to literally tens of thousands of near stars just because we haven't narrowed our search. If we could only afford to listen, we might be deciding to commit to a project that would have to run for hundreds of years, and the human race has been pretty reluctant to try such long term feats, and not real good at keeping civilizations going long enough to finish them.
On the other hand, if planets in vital zones are common, designing instruments to specifically look for signs of life on them makes more sense. If we find evidence of life, we can then look at other, easier to detect factors, such as how old the related stars are, and we end up with a list of places that might have advanced lifeforms with intelligence, and even technology such as radio. There's a fair chance we could work through that list in just a few years. It becomes a small enough project we could tackle it with what resources we have, and the people who start the project would live long enough to see the answers.
The payoff could still be huge! Just as huge as a more scattershot approach, for much less time and money. Imagine if we found ourselves talking with a civilization that had already figured out fusion power, or foolproof ways to keep nuclear war from happening, or some other technology we won't invent by ourselves for a hundred years, a thousand years, or more. That's the potential big payout. The next tier down might be things such as just finding a civilization that has already passed through a long industrial pollution phase and cleaned up its old toxic waste dumps and such. Just knowing that they managed not to kill themselves off with some of the things we worry about is pretty valuable even if we don't know the details. Maybe we find aliens that are really good at physics, but don't know as much about industrial chemistry as we do. They want to trade how to make flying cars for our advanced secrets of how to make paint that weathers well in sunlight.
Re:Mote Exoplanets will always be found. (Score:4, Insightful)
Re:Conservative Approach (Score:3, Insightful)
According to the fine NASA press release, they want to see 3 transit events so more like 3 years for a planet in the habitable zone around a Sun like star.
Re:Mote Exoplanets will always be found. (Score:4, Insightful)
Honestly, we can only see the nearest handful of stars compared to all planets in all galaxies. If we found even just one planet like earth, the fact that there are two such planets within proximity of each other is strong evidence there really are billions. We're finding lots of the planets that are easy to detect, what you're saying is a bit like searching through the sand with a coarse masked net and concluding there's only big rocks. Even an earth-style Jupiter would be very, very hard to detect despite its size because it has an orbital period of 12 years. They'd like 3x for confirmation, that's 36 years at the earliest. An earth-like planet goes faster but requires a lot higher resolution, and 3x1 year for confirmation is not particularly fast. I imagine by 2100 they'll look back at this discussion and laugh, of course there's pebbles where there's rocks. The only real reason not to think so is that some people have a very strong emotional investment in the earth and humanity being special.