With at least a hundred billion galaxies in the observable Universe and two hundred billion stars in Earth's Milky Way alone, the potential for planets with the conditions to support human-like life is considerate. But there is no solid evidence that such a planet exists.
However, on December 5, 2011, the United States space agency, NASA, announced [1] the Kepler Space Telescope discovery of Kepler-22b, [2] a planet within the right distance of its star for potentially having a habitable temperature. Science bloggers have reacted to the news with analysis and theories of their own.
[3]Diagram comparing Earth's solar system to an artist's rendition of Kepler-22b, a star system containing the first "habitable zone" planet discovered by NASA's Kepler mission. Image credit: NASA/Ames/JPL-Caltech
Hampshire College astronomy professor Salman Hameed is excited about the discovery [4]:
Yes. Astronomers have the first confirmed detection of an earth-like planet located in the star's habitable zone – the distance from the star where water can exist in liquid form…The discovery is amazing, if not really surprising. There are just too many planets out there, and we are bound to find planets in places that match conditions of the Earth. And life is also likely to be quite common. Life that can build telescopes? Don't know.
He gives more details:
So what do we know about this planet? It is called Kepler 22b. This is the sexiest name that astronomers could come up with (actually, it is because it is discovered by Kepler telescope). It is located about 600 light years away – just far enough that we can't start thinking about packing our bags for a trip…
Is there life there? We don't know. This planet was detected when it passed in front of its star, dimming the light of the parent star a bit. We do not have an image of the planet. When we do – and it may take years – then we can potentially analyze the composition of its atmosphere. The presence of oxygen in the atmosphere will be a good indicator for life, as oxygen in our own atmosphere is a by-product of life itself.
We are getting closer to finding life.
Helen Chappell [5], a former astronomer who studied physics at University of Colorado Boulder, offers three reasons why she doesn't care about Kepler-22b:
Kepler is finding hundreds of extrasolar planets, and it’s going to keep on finding hundreds more until the project’s funding runs out. Kepler 22b is just the poster child for NASA’s announcement of more than 1,000 new planet candidates.
[..]
Venus [like Kepler 22b] isn’t too far outside the habitable zone…[but] we know that it’s actually hot enough to melt lead on the surface. Venus is not a nice place for life, but extraterrestrial astronomers would have no way to figure that out if they used the same technology as us. Perhaps folks on Kepler 22b are giddy at the prospect of life on Venus.
[…]
We have no clear way to figure out whether Kepler 22b — or any other extrasolar planet — actually harbors life.
She does see one positive aspect of the excitement over the discovery:
Discoveries like Kepler 22b get everyone excited about astronomy, and open up opportunities to teach folks (especially kids) about science.
[…]
So hooray for science, even if I just burst your Kepler 22b bubble.
Another critic, an anonymous blogger who studies tornadoes for living, discusses misconceptions about Kepler-22b, concluding [6] nevertheless:
It's a first step, and it's a step we've never taken before. That's big news! And the fact that we still have 48 other candidate planets in the habitable zones of their respective stars is a Big Deal. But it's news in a way that a lot of the media seems to be missing out on.
In the comments section, the blogger discusses the actual distance between us and Kepler-22b:
At present top speeds, it'd take us, what, tens of millions of years to get there. That's a bit beyond even the scifi-ish dreams of generation ships and cryostasis. And the corollary to that: any further observations we make will be of the planet as it was 600 years ago.
600 light years may sound a lot, but it is minute in astronomical terms, even if it would take millions of years to travel to Kepler 22b at our current speeds. If we were able to build a machine traveling close to the speed of light, it might be possible to survive travel to Kepler 22b since, according to Einstein's Theory of Relativity, the travelers would experience less, about 24 years.
Some bloggers have expanded on the idea of space travel with some less serious than others.
Eight Days to Amish, a blog by freelance writer Chris Rodell, writes [7]:
I’m sure the Republicans thought, “Hallelujah! Now, there’s a place the lousy Democrats can Occupy for as long as they want!”
The Democrats thought, “You can bet greedy Republicans are already packing their Louis Vuitton suitcases, drilling rigs and barrels of Halliburton fracking liquids to exploit yet another pristine wilderness before Obama declares it off-limits.”
Advocatus Atheist, a blog by Tristan D. Vick, an English teacher in Japan, is more hopeful about communicating with Kepler-22b, if it were to have a civilization capable of space communication. He suggests [8] building a wormhole [9] (a hypothetical shortcut through spacetime), which would make it possible to communicate. He admits, however, that his suggestion is only possible theoretically.
Vick concludes in what seems to be a good summary of the lesson of Kepler-22b:
Regardless of whether or not we could ever make first contact with an alien race, it seems to me that Kepler 22B represents a dream which all people share–the dream of adventure, of interstellar travel, and of being a part of history. It seems to me, we may already be witnessing history in the making and not even truly be aware of it.