One In Five Sun-Like Stars May Have an Earth-Like Planet

The Bad Astronomer writes "A new study, looking at over 40,000 stars viewed by the Kepler spacecraft, indicates that 22% of stars like the Sun should have Earth-like planets orbiting them — planets that are similar in size to our home world and with a surface temperature hospitable for liquid water. There are some caveats (they don't include atmospheric issues like the greenhouse effect, which may reduce the overall number, or at cooler stars where there may be many more such planets) but their numbers indicate there could be several billion planets similar to Earth in the Milky Way alone."

Re:Maybe won't make any difference

[MightyMartian]

Unless, of course, y'know, we don't know everything there is to know about physics.

Re:Only 22% ?

[Your.Master]

There's a near-zero chance that your exact genetic sequence would ever come into existence during the course of the universe as we understand it, and yet you exist. The same is true for basically everyone else, yet identical twins exist which doubly-defy the odds! You're more likely to bit struck by lightning than to jackpot a big lottery, yet those lottery winners exist too. So do people struck by lightning, as a matter of fact.

By definition, the planet we arose on is Earth-like because that's the prototype to which all other planets are compared for Earth-likeness. There is a 100% chance that the planet we arose on is Earth-like. Also, there's nearly 100% chance that the first non-Earth planet that we inhabit to the same degree that we inhabit Earth now is also Earth-like, since we'll likely aim for the Earth-like ones, since, again pretty much by definition, we are biologically adapted to live in Earth-like planets.

Re:Maybe won't make any difference

[MightyMartian]

Even if that turns out to be the case, the one thing we may develop in the future are better ways of harnessing energy. Even if the speed of light remains the limit, and no feasible way around it (ie. wormholes, warp, whatever), we could still conceivably accelerate spacecraft to a reasonably high fraction of c which would, while not helping out observers on Earth, allow voyagers, one way or the other, to reach other stars in far less time. Tens of thousands of years to the nearest possible lifebearing solar systems could be dropped to a few centuries.

Re:Maybe won't make any difference

[Dr. Spork]

If we traveled at 10% the speed of light (fast but not requiring a breakthrough in fundamental physics), and built new exploration ships at each destination we colonize, it would only take a half a million years to colonize every single star in the Milky Way (source [wikipedia.org]). That's an absolute eyeblink in comparison to the age of our galaxy. I don't think it will be long before we can launch ships that could reproduce themselves and keep colonizing. Our children's generation will be investing serious research money in AI robotic systems that do asteroid mining, smelting and refining of ores. Once we get a workable .1c spaceship design, I'm sure we'll have robots that could build the things in space, from materials harvested in space. I don't think we're talking about some sci-fi fantasy land. I think we're talking about the foreseeable future. And all this invites the question: if we're so far along the process to colonizing the galaxy, why haven't one of the countless probable civilizations beaten us to it? Or if they had, why is there no trace of their colonies? That's at the core of the Fermi paradox.