--%>
Assignment Help - homework help

Explain Drake equation

Drake equation (F. Drake; 1961): The method of estimating the number of intelligent, scientific species (that is, able to communicate with other species) in subsistence in our space.

N = R fp ne fl fi ft L.

Here,

N is the number of species explained above at any specified moment in our Galaxy. The parameters it is evaluated from are as follows:

R = the rate of star formation in our solar system (in stars per year);
fp = the fraction of stars that contain planets;
ne = the total number of habitable planets per system with planets;
fl = the fraction of habitable planets on which the life arises;
fi = the fraction of such planets on which the life develops intelligence;
ft = the fraction of such planets where the intelligence grows into a technological civilization which is capable of communication; and
L = the mean life-time of such a scientific civilization.

Out of these quantities, only the first -- R -- is recognized with anything like any reliability; this is on the order of 10 stars per year. The others, most particularly the fractions, are approximately totally pure speculation at this point. Computations made by respectable astronomers vary by something like ten orders of magnitude in the last estimation of the number of species out there.

   Related Questions in Physics

  • Q : Heating a bucket of water than the cup

    Briefly describe the reason why it takes longer to heat a bucket of water than the cup of water?

    		•
  • Q : Define Noether theorem Noether theorem

    Noether theorem (Noether): A theorem that explains that symmetries are what gives rise to conserved quantities. For example, the translational symmetry (that is the fact that the laws of physics work the same in all positions) gives r

    		•
  • Q : What do you mean by the term density

    What do you mean by the term density? Briefly explain it.

    		•
  • Q : What do you mean by the term alloy What

    What do you mean by the term alloy? Briefly illustrate it.

    		•
  • Q : Define Singularity Singularity : The

    Singularity: The center of a black hole, where the curvature of space-time is maximal. At singularity, the gravitational tides deviate; no solid object can yet theoretically survive beating the singularity. Though singularities usually predict inconsi

    		•
  • Q : Define Tardon Tardon : A particle that

    Tardon: A particle that has a positive real mass and travels at a speed very less than c in all inertial frames.

    		•
  • Q : Define Doppler Effect Doppler Effect

    Doppler Effect (C.J. Doppler): The waves emitted by a moving object as received by an observer will be blue shifted (compressed) when approaching, redshifted (that is, elongated) if receding. This takes place both in sound and also el

    		•
  • Q : What is Ground source Heat Pumps Ground

    Ground source Heat Pumps (GSHP): This technology makes use of the energy stored in the earth’s crust, which comes mainly from solar radiation. Fundamentally, heat pumps take up heat at a certain temperature and discharge it at a higher temperatu

    		•
  • Q : What is Laplace equation Laplace

    Laplace equation (P. Laplace): For the steady-state heat conduction in 1-dimension, the temperature distribution is the explanation to Laplace's equation, which defines that the second derivative of temperature with respect to displac

    		•
  • Q : Define Metre or SI unit of length Metre

    Metre: meter; m: The basic SI unit of length, stated as the length of the path traveled by light in vacuum throughout a period of 1/299 792 458 s.

    		•