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."

Comments

Maybe won't make any difference

[gmuslera]

If the speed of light is the absolute max speed in the universe, with no shortcuts in practice, getting somewhere outside of local star group won't be ever possible, and the same will be for everyone else, no matter how advanced they are, and how much similarities are between their culture and ours (at least, our culture willingness to go to space and communicate with others). And, of course, there is time, they should be at the right stage of their civilization, of the 4.5billon years of this planet just in the last 100 we were sending and trying to hear signals to/from somewhere else, and not sure for how much time we will be around. And if well could be earth-like planets "close", sending an expedition even to the closest solar system to just plant a flag is outside our reach, maybe for centuries (and getting there and back will take even more centuries)

The universe may be full of life and advanced civilizations, and we probably won't ever know that someone else is out there. Nor them.

Re:Maybe won't make any difference

[MightyMartian]

Exactly. We don't know what we don't know. So yes, at the moment, the best we can do is find these planets, see if we can recognize the signatures of life (the discovery of which would be monumental whether we can ever get there or not), and bequeath that information to future generations who may have far greater technical and scientific capabilities than we do.

Re:Maybe won't make any difference

[Xtifr]

Actually, if you go fast enough, you don't need life-extension. The stuff you left behind may be 50,000 years out of reach, but you might only have experienced a couple of dozen years.

Unfortunately, we're probably at least as far from the necessary accelerations (and cushioning) as we are from the necessary life-extension techniques, so it's probably a moot point, but I value completeness. :)

Re:Maybe won't make any difference

[amicusNYCL]

If the speed of light is the absolute max speed in the universe, with no shortcuts in practice

That's a pretty big "if", though, isn't it? We aren't nearly qualified to even speculate on the answer to that question. If you consider the distances even in our own solar system, where the planets are enormous distances from each other compared with the scale we know, our experience of manned exploration goes from the Earth to the Moon, no farther. We still have a lot to learn. We'll blow ourselves up long before we learn it, but still, there's a lot we don't know.

We've recently celebrated the accomplishments of the Voyager probes. The Flight Data System computers on both Voyager spacecraft are 16-bit machines with a whopping 16KB of memory. Each spacecraft had a total of 6 computers, with a total memory of around 68KB. The CPU clock speeds are around 250KHz, although since it takes around 80 microseconds to execute an instruction, that makes around 8,000 instructions per second.

The phone in my pocket has 2GB of memory and 4 CPUs running at 1.7GHz. So my phone has around 30,000 times as much memory as Voyager, and the CPU is ... well, my math isn't that good. 3.39 DMIPS/MHz is how many instructions per second for a quad-core Krait 300 1.7GHz chip again? I think it's 4.2 Brazilian times faster at Getting Stuff Done.

Anyway, we're pretty stupid around this planet. That's my point. I think I made it.

Re:Maybe won't make any difference

[MightyMartian]

If we're postulating that in the next few centuries we come up with energy sources that could accelerate us to something like 20% of c, then I'd say we probably have the tech to build the shielding. We'd have to, as moving at such a high fraction of c means radiation approaching us going to be blue shifted, and thus more intense.

But hey, if it makes you feel special to imagine we're doomed and that there is some sort of limit on the kinds of technologies that we can develop to deal with what would still remain problems of physics as we understand it now, be my guest.

We will get there eventually.

[TiggertheMad]

If the speed of light is the absolute max speed in the universe, with no shortcuts in practice,

You know, I have always suspected that there will be ways for people with very advanced science to get around speed of light problem. Several hundred years ago, gravity was a similar looking, insurmountable barrier, and that has proven to be be trivial to 'get around' provided you are willing to make the proper engineering choices. Gravity and relativity are still things we don't have a lot of understanding of, and there is plenty to learn about how and why they work.

Nuclear Pulse Propulsion

[Anonymous Coward]

I don't believe we need to go faster than light to get somewhere. Toss in a good fraction of that, say 20% or as little as 10% and things begin to appear a little closer. Within 16 light years there are 53 other stars. At 10% of light speed that is 160 years traveling time, and arguably we could do it now with the proper resources and political will. At 20% - not far off - that is 80 years. Now consider genetic modification or other advances in medical science to prolong human life. If we do so much as double the human life span, 80 years will seem more like 40. Now consider multi-generational ships. I hope more than I could ever convey that there is a way to go faster than light, that there is some shortcut to the wider universe. But even if there isn't, I wouldn't be so defeatist as to suggest we're stuck here or, respectfully, so myopic as to suggest that traveling beyond our solar system would be a futile exercise. While I do fear what is in store for humanity these coming decades and do often wonder whether we're effectively doomed to kill ourselves off long before any of the above is considered seriously by anyone with real power, or the population as a whole, I have hope.

As for E.T. I wouldn't give up quite yet: http://xkcd.com/638/