--%>
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 : 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.

    		•
  • Q : Faradays laws of electromagnetic

    Explain Faraday's laws of electromagnetic induction and explain Faraday's first, second and third law of electromagnetic induction? Faraday's laws of electromagnetic in

    		•
  • Q : Brewster's law Brewster's law (D.

    Brewster's law (D. Brewster) - The extent or level of the polarization of light reflected from a transparent surface is maximum whenever the reflected ray is at right angle to the refracted ray.  

    		•
  • Q : Explain Maxwells equations and its

    Explain Maxwells equations and its four elegant equation? Maxwell's equations (J.C. Maxwell; 1864): The four elegant equations that explain classical electroma

    		•
  • Q : Explain Michelson-Morley experiment

    Michelson-Morley experiment (A.A. Michelson, E.W. Morley; 1887): Probably the most famous null-experiment of all time, designed to confirm the existence of the proposed "lumeniferous aether" via which light waves were considered to pr

    		•
  • Q : When the intermolecular forces are

    Describe when the intermolecular forces are strongest? Briefly state it.

    		•
  • Q : Problem on two coupled coils connected

    In a series adding connection, two coupled coils have equivalent inductances LA; in a series opposing connection, LB. Determine an expression for M in terms of LA and LB. What does the outcome suggest?

    		•
  • Q : What is Simultaneity principle

    Simultaneity principle: The principle which all frames of reference will contain invariant simultaneity; that is, the two events perceived as simultaneous (that is, containing the similar time coordinate) in one frame will be apparent as simultaneous

    		•
  • Q : Fission and Fusion What do you mean by

    What do you mean by Fission and Fusion?

    		•
  • Q : Define Mediocrity principle Mediocrity

    Mediocrity principle: The principle that there is nothing predominantly interesting about our position in space or time, or regarding ourselves. This principle most likely first made its real manifestation in the scientific community whenever Shapley

    		•