Finding Twin Earths Is Harder Than We Thought

Matt_dk writes "Does a twin Earth exist somewhere in our galaxy? Astronomers are getting closer and closer to finding an Earth-sized planet in an Earth-like orbit. NASA's Kepler spacecraft just launched to find such worlds. Once the search succeeds, the next questions driving research will be: Is that planet habitable? Does it have an Earth-like atmosphere? Answering those questions will not be easy. 'We'll have to be really lucky to decipher an Earth-like planet's atmosphere during a transit event so that we can tell it is Earth-like,' said Kaltenegger. 'We will need to add up many transits to do so — hundreds of them, even for stars as close as 20 light-years away.'" The abstract of their paper offers a link to the complete paper as a 17-page PDF; here is a short description from 2007 of the same researchers' work, outlining the type of spectral signature that an Earth-like atmosphere would be expected to show.

Comments

In effect, what they are saying, is

[Jane Q. Public]

that it will take hundreds of years to tell if they are truly Earth-like. And that is complete nonsense.

Once we find a sufficient collection of candidate planets using this instrument, we can devise a different device/experiment to narrow down whether they are Earth-like. That should take maybe a few years to ten years.

That is more-or-less the pattern we have been following, and it has been successful so far. I see no reason to change.

Re:In effect, what they are saying, is

[forand]

IAAP (I am an astro-physicist) and while I would love to agree with you, I cannot. The problem is not that we do not know how to get a quick measurement the problem is that is would take huge sums of money as well as very significant technological improvements.

Science is being limited much more by funding and physical constraints. Current ground based telescopes are operating very near the quantum limit and space based observatories are expensive to the point of making them infeasible.

All in all I think that pointing a few telescopes at a given object for long periods of time for a total cost far exceeding that of building a better solution is the path that is being (and will continue to be) pushed on the scientific community. The prices tags for what we want to know are so large and budgets tend to be sabotaged by political agendas as to make it appear that we are incapable of doing science for a reasonable price.

Re:As much as I'd love to find another Earth...

[Farmer Tim]

I'm fairly certain that the little green men, ticked off after years of being depicted as scrawny, bug-eyed, space-faring bobbleheads, will just come in rayguns blazing, but the machines, prizing efficiency and precision above our human failings, would probably arrive and play muzak with a pre-recorded voiceover telling us that our death is important, and would we please wait.

Is being blasted into your component molecules by unimaginably powerful energy beams really more distressing than being put on hold?