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

Only 22% ?

[TechnoCore]

There's a 78% chance we're not living on an earth-like planet. It does however support life. Are their models really that good?

Re:Only 22% ?

[Anonymous Coward]

Well, there's a 71% chance that if you're on the Earth, you'll drown.

Re:Only 22% ?

[Mitchell314]

There's a >0.0000000000000000000000001% chance that you exist in this position and state in the universe. So stop doing it.

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:Face it, folks

[Skarecrow77]

and these aliens had thunderbolt hammer that were really nuclear weapons, and they flew around in vimanas which were really flying ships from a floating castle mothership, in order to interbreed with earth's primitive dwellers by taking human form.

I love Ancient Aliens. one of the best shows on TV. Watching them come up with their wild pseudoscience theories is like watching a monkey discover how a cigarette lighter works.

Re:Face it, folks

[ackthpt]

Our planet Earth was terraformed. BY ALIENS!!!!!

And we are but fertilizer...

which explains a lot of what I see on Fox News

Re:Face it, folks

[Mitchell314]

And the aliens tried to breed the most intelligent of various species to bolster the mental capacity to match theirs. The rejects they sent to work for the history channel.

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]

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

Re:Maybe won't make any difference

[WrongMonkey]

The distances only seem insurmountable because of the limit of human life spans. If we could develop a way to extend our life span indefinitely, then taking a trip to another star might be an interesting 50,000 year vacation.

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

[cavreader]

I am just glad there are still some very smart people out there still working on the physics of the universe. There may very well be no way to realistically travel to far way star systems but we will never know if we claim universal understanding of everything and then just stop investigating.

Re: Maybe won't make any difference

[Anonymous Coward]

Accelerating at a constant 1G would take something like a year to reach 99% light-speed..

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

[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.

Re:Maybe won't make any difference

[Gravis Zero]

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).

you seem to have forgotten relativity. if you get to really close to C then you could travel millions of parsecs in what would seem like an hour. it would seem like most of your trip was spent accelerating and slowing down when really that hour took you much further than anything else. then again, you may want to put yourself into solid or suspended state to avoid issues with acceleration and you could travel slower if you wanted. interstellar and even intergalactic travel is completely possible. the only limiting factor is the dedication to figuring how to make such a propulsion system. oh and the whole space dust argument is stupid because if you have that much power, you might as well make a large high density mass shield.

also, you have discounted the possibility of generating wormholes or anything else that we dont know about.

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). 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.

Re:Maybe won't make any difference

[jafac]

Solution:
Build the ship out of uranium.

As you approach c, it becomes more mass. Feed that mass into a nuclear reactor to drive the propulsion. Ship becomes less massive. Science, bitches. :)

Drake Equation

[Continental Drift]

Quick, update the Drake Equation results to 100%!

Re:But in a cruel twist of fate,

[ackthpt]

So much for intelligent life... on THIS planet.

Hey, I don't see you complaining about unsanitary telephones!

Once upon a time...

[bob_super]

What cracks me up is that not twenty years ago, I had a long discussion with a physics teacher who must not have listened to his own material and kept on arguing that we were probably the only star with a planetary system.

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.

Re:We will get there eventually.

[rroman]

There is a big difference. If the theories we know are correct, then FTL information transmission can violate causality. c isn't just a speed limit which we are "not yet able to beat", its violation would violate basic principles of our existence.

Shade of Sagan

[kermidge]

I can just see, wherever he is, his wicked-fine smile at partial affirmation of some of his speculation.

One of the beauties of Universe is the slew of un-answered questions; that so few seem to give a damn, one of its uglies.

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/

Re:Are ya?

[ArcadeMan]

There's a 1.333739068902037589% chance that I'm using a Pentium for my calculations.

Re:But in a cruel twist of fate,

[roc97007]

So much for intelligent life... on THIS planet.

Hey, I don't see you complaining about unsanitary telephones!

I've often suspected that our planet was colonized by the "B" ark. There's so many indicators... The Kardashians, reality TV in general, pop music, sensationalist news, congressional press releases, the MPAA, offshore helpdesks, Snooki being on TV for any reason whatsoever, Darwin awards, the Kardashians. Pretty much confirmed, really.

Re:But in a cruel twist of fate,

[the gnat]

The Kardashians, reality TV in general, pop music, sensationalist news, congressional press releases, the MPAA, offshore helpdesks, Snooki being on TV for any reason whatsoever, Darwin awards, the Kardashians

An optimist - and for these purposes, I qualify - might look and think, "isn't it wonderful that the only reason any of this crap is relevant is that we have a global communications network that can transmit any information at the speed of light to billions of people?" The same optimist would probably point out that in 100 years, virtually no one will remember who Snooki or the Kardashian sisters were, outside of a few obsessively geeky historians of pop culture.

Meanwhile, thanks to the same global communications network, I have access to a vast trove of scientific research, millions upon millions of lines of open-source code, instant answers to my programming questions, and whatever out-of-copyright works have been digitized. Oh, and I can access all this on a computer that fits in my pocket and is significantly more powerful than anything I used as a child.