Is there an extraterrestrial? If have, where is the extraterrestrial?
The universe is too large.
Every time we look up look up at the Milky Way, total meeting plaints Yu Xing's empty vast and strong beautiful. But what your place does not know is, the star of the great majority that we can see, it is a fraction in the galaxy merely actually.
In the galaxy that is in in us, having about 250 billion star, namely 250 billion suns. And in whole universe, also having the universe like one billion two hundred and fifteen million seven hundred and fifty-two thousand one hundred and ninety-two several galaxies. What do this mean?
This is meant, the sidereal gross in the universe, amount to 5*10^20 probably.
Is this a how old number?
500, 000, 000, 000, 000, 000, 000
With respect to so much.
Good, we catch hypothesis next:
Inside 100 each star, ability can have a star, can have a planet that suits life existence fortunately
Inside 100 each planets that suit life existence, ability can have a planet, produced life really
Inside 100 each planets that produced life truly, ability can have a planet, multiply went out to be able to master the civilization of the advanced technique
Civilization of how many wisdom can there be in the universe so?
-2009260032! ! !
-2009260032! ! !
-2009260032! ! !
But in observation universe, have 100 billion universe about, that is meant, there can be civilization of about 500 wisdoms in the galaxy! They may be earlier than us, the likelihood is later than us.
The earth has age of 4.5 billion years, and the earliest planet has about 8 billion years old. If life generation was in on these old planets, that has reason to believe, they went more than us full 3 billion years.
The ancients before we look 200 years now, the feeling has been a sky an underground. That if this " 200 years " does enlarge arrive " 200 million years " ?
It is probably before those old culture, we are inferior to even paramecium.
But we never had seen them.
SETI (Search For Extraterrestrial Intelligence, the civilization outside the ground seeks a plan) it is the organization that signal of civilization of an intelligence outside coming from the ground with listening is a purpose. If civilization of 100 thousand intelligence exists in the galaxy, even if emit radio wave external partly rarely only among them,perhaps stimulate beam of light or other contacts signal, the satellitic array of SETI should be met get various signal.
But not. Do not have.
So are they in?
Have a very interesting explanation, call a serious offence colander. Those who say is, we were underestimated actually, arrive from barren land interstellar journey, in this, the difficulty of certain key measure.
Perhaps had had countless heavenly bodies, produced individual life successfully, but these life because the bank with very big certain, cannot finish final " interstellar journey " mission, also cannot be seen by us.
This bank what be?
More hopeful estimation is, this bank the likelihood is " science " . Be in on the earth in the meantime in genetic a lot of civilization, mere, development went " science " . We have reason to believe, this are accomplished very hard. And if the universe is medium,only we can accomplish this, and we had become fokelore medium interstellar " leading sheep " , other extraterrestrial is returned too dish, that nature is very appropriate, they still are waiting for us to look for them.
And more pessimistic is, this bank the likelihood is " interstellar journey " . The extraterrestrial may precede we are counted year, but even if is this several years accumulate, also can't let them obtain the capability of interstellar journey, also cannot be gone to by our observation. But if such word, the mankind basically also lost the swaddling clothes that leaves the world, move toward the hope of stars sea.
Is there an extraterrestrial? If have, are they in?
Fine really think of extremely fear.
