Formula for the existence of other life forms.?

Question

Is there an acceptable equation that answers the question of the possibility of life on other planets.??

Answer 1

You are thinking of the Drake Equation, a famous result in the speculative fields of xenobiology, astrosociobiology and the search for extraterrestrial intelligence.

This equation was devised by Dr. Frank Drake (a professor at the University of California, Santa Cruz) in the 1960s in an attempt to estimate the number of extraterrestrial civilizations in our galaxy with which we might come in contact. The main purpose of the equation is to allow scientists to quantify the uncertainty of the factors which determine the number of extraterrestrial civilizations.

In recent years, the Rare Earth hypothesis, which posits that conditions for intelligent life are quite rare in the universe, has been seen as a possible refutation of the equation.

The Drake equation states that:

N = R* x fp x ne x fl x fi x fc x L

where:

N is the number of civilizations in our galaxy with which we might expect to be able to communicate at any given time
and

R* is the rate of star formation in our galaxy

fp is the fraction of those stars that have planets

ne is average number of planets that can potentially support life per star that has planets

fl is the fraction of the above that actually go on to develop life

fi is the fraction of the above that actually go on to develop intelligent life

fc is the fraction of the above that are willing and able to communicate

L is the expected lifetime of such a civilization

Historical estimates of the parameters
Considerable disagreement on the values of most of these parameters exists, but the values used by Drake and his colleagues in 1961 were:

R* = 10/year,
fp = 0.5,
ne = 2,
fl = 1,
fi = 0.01,
fc = 0.01,
and L = 10,000 years.

The value of R* is the least disputed. fp is less certain, but is still much firmer than the values following. Confidence in ne was once higher, but the discovery of numerous gas giants in close orbit with their stars has introduced doubt that life-supporting planets commonly survive the creation of their stellar systems. In addition, most stars in our galaxy are red dwarfs, which have little of the ultraviolet radiation that has contributed to the evolution of life on Earth. Instead they flare violently, mostly in X-rays — a property not conducive to life as we know it (simulations also suggest that these bursts erode planetary atmospheres). The possibility of life on moons of gas giants (e.g. Jupiter's satellite Europa) adds further uncertainty to this figure.

Geological evidence from the Earth suggests that fl may be very high; life on Earth appears to have begun around the same time as favourable conditions arose, suggesting that abiogenesis may be relatively common once conditions are right. However, this evidence only looks at the Earth (a single model planet), and contains anthropic bias, as the planet of study was not chosen randomly, but by the living organisms that already inhabit it (ourselves). Also countering this argument is that there is no evidence for abiogenesis occurring more than once on the Earth—that is, all terrestrial life stems from a common origin. If abiogenesis was more common it would be speculated to have occurred more than once on the Earth.

Similar arguments can be made regarding fi and fc by considering the Earth as a model: intelligence with the capacity of extraterrestrial communication occurs only in one species in the 4 billion year history of life on Earth. If generalised, this mean only relatively old planets may have intelligent life capabale of extraterrestrial communication. Again this model has a large anthropic bias.

Note that the capacity and willingness to participate in extraterrestrial communication has come relatively "quickly", with the Earth having only a 100,000 year history of intelligent life without it.

One piece of data which would have major impact on fl is the discovery of life on Mars or other planet or moon. If life were to be found on Mars which developed independently from life on Earth it would imply a higher value for fl.

fi, fc and L, like fl, are little more than guesses. fi has been affected by discoveries that the solar system's orbit is circular in the galaxy, at such a distance that it remains out of the spiral arms for hundreds of millions of years (evading radiation from novae). Also, Earth's very large, unusual moon appears to aid retention of hydrogen by breaking up the crust, inducing a magnetosphere by tidal heating and stirring, and stabilizing the planet's axis of rotation. In addition while it appears that life developed soon after the formation of Earth, the Cambrian explosion in which a large variety of multicellular life forms came into being occurred considerable amounts of time after the formation of Earth, which suggests the possibility that special conditions were necessary for this to occur. In addition some scenarios such as the Snowball Earth or research into the extinction events have raised the possibility that life on Earth is relatively fragile. Again, the controversy over life on Mars is relevant since a discovery that life did form on Mars but ceased to exist would affect estimates of these terms.

The well-known astronomer Carl Sagan speculated that all of the terms, except for the lifetime of a civilization, are relatively high and the determining factor in whether there are large or small numbers of civilizations in the universe is the civilization lifetime, or in other words, the ability of technological civilizations to avoid self-destruction. In Sagan's case, the Drake equation was a strong motivating factor for his interest in environmental issues and his efforts to warn against the dangers of nuclear warfare.

(Note, however, that in the year 2001 a value of 50,000 for L can be used with exactly the same degree of confidence that Drake had in using 10,000 in the year 1961.)

The remarkable thing about the Drake equation is that by plugging in apparently allegedly "plausible" values for each of the parameters above, the resultant expectant value of N is generally often >> 1. This has provided considerable motivation for the SETI movement. However, this conflicts with the currently observed value of N = 1; i.e., one observed civilization in the entire galaxy.

Answer 2

If you mean the Drake equation, there is nothing really acceptable about it.

The Drake equation is really a meaningless formula because nobody has enough observational knowledge to justify a single number applied to the equation.

All of the factors involved are purely theoretical and none of the numbers used can be determined with any great certainty at this time and they were even more uncertain then.

The fact is that no probability can actually be computed without certain knowledge of the variables.

The problem with the Drake equation is that most of the numbers have little at all to do with what we actually know about the universe, but more to do with what we wish to assume about it.

Scientifically, we cannot justify taking such an equation seriously.

It's a theoretical shot-in-the-dark with no certain aim.

By today's scientific standards the equation too vague to be of any real value.

But he tried.

We simply don't have enough knowledge to compute a reliable probability of life being found anywhere - not even on this planet.

Answer 3

I think you're referring to the Drake Equation, which you should be able to google. It doesn't really answer the question because each term of the equation involves an assumption, but you can still have fun with it by making different assumptions and seeing how the numbers turn out. Personally, I think life of some sort is pretty common in the universe, but intelligent life like ours is probably quite rare. Since evolution doesn't "plan ahead" or "progress" in any way, the appearance of intelligent life on Earth is an accident which is highly unlikely to be repeated elsewhere. However, since bacteria appeared on Earth very early in our planet's history, they are probably easy to evolve and are likely to be quite common elsewhere. As far as multicellular life is concerned, that's still an open question. It took about one billion years or more to appear on Earth, so it might not be too common either. Until we can actually explore other planets in detail, all we can make are educated guesses based on what seem to be logical assumptions (but which could still be wrong).

Answer 4

the drake equation, which states
N=R* x fp x ne x fl x fi x fc x L

R= the number of stars
fp= the fraction of those stars that has planets
ne= the fraction of the above that can potentially support life
fl= the fraction of the above that actually does support life
fi= the fraction of the above that produces intelligent life
fc= the fraction of the above we will find out about the intelligent life
l= that the intelligent life will actually live long enough for us to find them

the chances seem pretty low, but there is a chance. besides, we dont have to go as far as intelligent life. Life could just mean a grasshopper. (obviously not something we would be able to identify such as a grasshopper but you get the idea)

Answer 5

The Drake Equation:
N = N* x fp x ne x fl x fi x fc x fL
N: Number of communicating civilizations in the galaxy (since we can only find the ones which communicate)
N*: Number of stars in the Galaxy
fp: Fraction of stars with planets around them
ne: Number of planets around a star capable of sustaining life (in any form)
fl: Fraction of above planest where life arises
fi: Fraction of above planets where intelligent life evolves
fc: Fraction of above life forms which desire to communicate with others.
fL: Fraction of the planet's life that the intelligent civilization exists

If you don't care that the life is intelligent you can stop at fi.

Answer 6

Yes. It's called the Drake Equation.

Answer 7

The Drake equation is probably the best known

http://en.wikipedia.org/wiki/Drake_equation

But have a look at the sample of references below and you'll soon see that there is not necessarily a scientific consensus.

I guess it all comes down to whether you're an optimist or pessimist.

Answer 8

42

Answer 9

I think we are looking in the wrong places we are being misdirected , i think we should look under our oceans and under our feet , there are possibilities that the world is hollow and there is a subterranean world with a central sun, this place is called agartha. Alien life forms and advanced beings may live here.

Answer 10

The drake equation is a useless POS.

The variables have such a huge range, some of which we don't even know (don't even know the range)... you really don't know the answer until you find the life.

Answer 11

Also i think a fellow named Enrico Fermi came up with an equation for something like that as well as Drake, i think it is called the Fermi Paradox, you should read this for more info.

I hope it helps.