Are there Billions of Planets With Life ?


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M-dwarfs, they're small, no more than half the size of our Sun at most. They're so dim that not a single one, not even the closest, is visible to the naked eye. And they vastly outnumber any other type of star in the Milky Way: our galaxy has maybe ten or 20 billion Sun-like G stars, but is home to 150 billion M-dwarfs, and maybe more, adding up to some 80% of the galaxy's stellar population.

Working at the European Southern Observatory in Chile, the scientists have completed a survey of 102 M-dwarf stars and identified a total of nine "super-Earths" -- planets up to 10 times larger than Earth -- circling them. Two of the nine lie in their stars' habitable zones, the Goldilocks region where temperatures are not too hot, not too cold, but just right for liquid water and thus, conceivably, for the existence of life. In the case of an M-dwarf, the star's cooler, dimmer fires mean that the Goldilocks zone is closer than it is around our hotter, brighter sun, but the water principle remains the same. And if you do the math for the entire galaxy, the recent survey means that tens of billions of Goldilocks planets are peppered throughout the Milky Way, with a hundred or so just in our solar system's immediate neighborhood.

For planet-hunters, that's an especially tantalizing prospect. Ground- and space-based telescopes have discovered many hundreds of worlds orbiting stars other than the Sun -- several thousand if you include likely but unconfirmed planets found by the orbiting Kepler probe. But most of them are so far away that the prospects of actually being able to determine whether they have life are exceedingly dim, even with a new generation of giant telescopes, because the planets themselves are so dim. With so many M-dwarfs right around the cosmic corner, however, and with so many relatively small planets orbiting in their habitable zones, the job will be orders of magnitude easier.

It's not guaranteed that a super Earth will necessarily be all that much like the real Earth. In our Solar System, there's a big size gap between Earth and Neptune, the next biggest planet, which is four times as big and 17 times as massive as our home world. Earth is rocky, while Neptune is made mostly of water, ammonia and methane.

Nobody knows where the cutoff might be between smaller, rocky worlds and larger, Neptune-like planets, but it might well be smack in the middle of the super-Earth range. A super Earth known as GJ 1214b, discovered in another M-dwarf survey, is 2.7 times the size of our planet, and is almost certainly a mini-Neptune. It's not in its star's habitable zone, but it wouldn't be a nice place to live there even if it were. Another super Earth, Kepler 10b, is 1.4 times Earth's size, and it's unquestionably rocky -- although it's far too close to its star, and far too hot, to be habitable.

Even if a fair fraction of the nine nearby super Earths the Europeans have discovered turn out to be rocky, moreover, there's another problem: M-dwarfs tend to be volatile beasts, with far more sunspot and flare activity than the Sun has, along with greater fluctuations in brightness. It might be tough for life to arise and survive in such a hostile environment, especially since the Goldilocks planets would be closer to all the flaring than the Earth is to the Sun.

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Of course there are billions of planets with life out there.

In our galaxy alone there are somewhere between 200 and 400 billions stars. And the Milky Way is one of, literally, billions of galaxies that we can see. Just using simple math using conversative percentages yields hundreds of millions to billions of planets that could have life. Anyone who thinks we're alone in the universe simply has their head up their ass.

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?It is known that there are an infinite number of worlds, simply because there is an infinite amount of space for them to be in. However, not every one of them is inhabited. Any finite number divided by infinity is as near nothing as makes no odds, so the average population of all the planets in the Universe can be said to be zero. From this it follows that the population of the whole Universe is also zero, and that any people you may meet from time to time are merely products of a deranged imagination.?

This sums it all up.

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We don't know the exact conditions needed for live to develop and survive, nor do we know how it developed. Therefore the drake equation, or other simple maths can not conceivably predict the likelihood of life. It drives me nuts when someone claims he can give an estimate of the number of planets with life based on an ill thought out extrapolation.

Get back to me when you know exactly how life started, then you'll have my attention, until then, I'll just ignore these mathematical blunders.

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Get back to me when you know exactly how life started, then you'll have my attention, until then, I'll just ignore these mathematical blunders.

On our planet? Probably from bacteria from another planet. :laugh:

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We don't know the exact conditions needed for live to develop and survive, nor do we know how it developed. Therefore the drake equation, or other simple maths can not conceivably predict the likelihood of life. It drives me nuts when someone claims he can give an estimate of the number of planets with life based on an ill thought out extrapolation.

Get back to me when you know exactly how life started, then you'll have my attention, until then, I'll just ignore these mathematical blunders.

Well, we know which ingredients are suitable for the complex chemistry that life requires. We know what sort of ambient conditions those molecules need for such chemistry. And we know that neither the ingredients nor the conditions are rare in the galaxy. Now, combine all that with inconceivably long periods of time.

It really doesn't matter if estimates are off by orders of magnitude. It still becomes rather clear: the probability that no other life exists in the galaxy is miniscule. Inversely, the probability that it exists many other places is high.

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"No!!!!! God created the earth and man. There is NO such thing as life on other planets!!!! "

- Bible Thumpers

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I find it absurd that people believe that out of the millions of billions of rocks floating about out there, ours is the only one capable of supporting any form of life. Never mind the fact that our lifeforms on earth are carbon based, and it has been proven that bacteria can survive in completely carbon-less environments.

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We don't know the exact conditions needed for live to develop and survive, nor do we know how it developed. Therefore the drake equation, or other simple maths can not conceivably predict the likelihood of life. It drives me nuts when someone claims he can give an estimate of the number of planets with life based on an ill thought out extrapolation.

Get back to me when you know exactly how life started, then you'll have my attention, until then, I'll just ignore these mathematical blunders.

True we don't know the exact conditions required to create life. But my point was that even if the possibility of all factors needed to create life coming together at the right time is infinitesimal; the universe is quite literally infinite. The sheer number of planets, stars, and galaxies out there is unfathomable. The numbers are so big, it is an absolute certainty that there is life on other planets.

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True we don't know the exact conditions required to create life. But my point was that even if the possibility of all factors needed to create life coming together at the right time is infinitesimal; the universe is quite literally infinite. The sheer number of planets, stars, and galaxies out there is unfathomable. The numbers are so big, it is an absolute certainty that there is life on other planets.

Since you think the the universe is "literally infinite" I am wondering what theory of how everything came to be as we know it you subscribe to. The universe is defined as "the totality of everything that exists,[1] including all matter and energy, the planets, stars, galaxies, and the contents of intergalactic space. Definitions and usage vary and similar terms include the cosmos, the world and nature"

Under that definition, and with the Big Bang Theory, the universe has the ability to expand into infinity, but is still a finite thing. The location we are at now was not part of the universe at the moment before the Big Bang. If you were to travel to the edge of the universe faster than the expansion, you would hit a void. If you traveled into the void, you would be expanding the universe.

So, since you under the Big Bang Theory the universe isn't infinite, I am wondering what other choices there are? I ask because I love reading into various creation theories. Favorite one to read about so far is the theory that to branes touched and created a ripple on both. The ripple on our brane is our universe. Under that one, the universe also isn't infinite.

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Since you think the the universe is "literally infinite" I am wondering what theory of how everything came to be as we know it you subscribe to. The universe is defined as "the totality of everything that exists,[1] including all matter and energy, the planets, stars, galaxies, and the contents of intergalactic space. Definitions and usage vary and similar terms include the cosmos, the world and nature"

Under that definition, and with the Big Bang Theory, the universe has the ability to expand into infinity, but is still a finite thing. The location we are at now was not part of the universe at the moment before the Big Bang. If you were to travel to the edge of the universe faster than the expansion, you would hit a void. If you traveled into the void, you would be expanding the universe.

So, since you under the Big Bang Theory the universe isn't infinite, I am wondering what other choices there are? I ask because I love reading into various creation theories. Favorite one to read about so far is the theory that to branes touched and created a ripple on both. The ripple on our brane is our universe. Under that one, the universe also isn't infinite.

I've been reading a ton on the updated Multiverse theories and what not, amazing stuff really.

Also, as the great Jeff Goldblum said in Jurrasic Park - Life finds a way.

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"No!!!!! God created the earth and man. There is NO such thing as life on other planets!!!! "

?- Bible Thumpers

Shows your ignorance - you forgot the heavens, and everything in them.

Major Catholic theologians had seriously explored the idea of otherworld life in a positive way as far back as the middle ages. The Vatican has had observatories since 1891 under Leo VII, the largest being the VATT (Vatican Advanced Technology Telescope) on Mr. Graham in Arizona and it has no objection to the idea of alien life or intelligence. The Lutherans and other mainline hurches likewise have no problem with the concept.

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Shows your ignorance. The Vatican has had observatories since 1891 under Leo VII, the largest being the VATT (Vatican Advanced Technology Telescope) on Mr. Graham in Arizona) and has no objection to the idea of alien life or intelligence. The Lutherans and other mainline hurches likewise have no problem with the concept.

Every bible thumper I have talked to thinks people are nuts to believe in aliens.

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Then you 're talking to an ignorant subset.

I could probably find as many, if not more, atheists who feel the same way. Some of them are astrophysicists who also have a problem with the odds. One is Howard Smith, a senior astrophysicist at Harvard, who just last year was quite skeptical.

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Every bible thumper I have talked to thinks people are nuts to believe in aliens.

Maybe it's just your area. Although it can't be as bad as Oklahoma. (Sorry, Okies :p)

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Every bible thumper I have talked to thinks people are nuts to believe in aliens.

Technically if you believe in god, you believe in an alien.

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Rough estimates state there about 100 billion galaxies in the known universe, on average about 100 billion stars in each galaxy, and several planets orbiting most of them. Assuming 10 planets per star:

100,000,000,000,000,000,000,000 or 100 sextillion planets.

To put this into perspective: There are an estimated 7 billion people. If each person on earth could check one planet per second for the existence of life, it would take us ~453,000 years to check all the planets in the known universe.... assuming 10 planets per star....

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I'd also like to mention that amino-acids, the building blocks of life, are found on meteorites which means that the Universe is literally seeded with life.

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