--%>
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 : Balanced field takeoff Describe the

    Describe the process of balanced field takeoff in brief?

    		•
  • Q : Define Luxon Luxon : The particle that

    Luxon: The particle that travels solely at c (that is the speed of light in vacuum). All luxons have a rest mass of exactly zero. Though they are mass less, luxons do take momentum. The photons are the prime illustration of luxons (that is the name it

    		•
  • Q : Define Universal constant of gravitation

    Universal constant of gravitation: G The constant of proportionality in the Newton’s law of universal gravitation and that plays a comparable role in Sir Einstein's general relativity. This is equivalent to the 6.672 x 10-1

    		•
  • Q : What is Bernoulli's equation

    Bernoulli's equation - In an ir-rotational fluid, the sum of static pressure, the weight of the fluid per unit mass times the height and half of the density times the velocity squared is steady all through the fluid 

    		•
  • Q : What is Ultraviolet catastrophe

    Ultraviolet catastrophe: It is the shortcoming of Rayleigh-Jeans formula that attempted to explain the radiance of a blackbody at different frequencies of the electromagnetic spectrum. This was clearly wrong since as the frequency rose, the radiance r

    		•
  • Q : How radiation emitted from the body

    Describe the procedure how radiation emitted from the body? Illustrate in brief.

    		•
  • Q : Explain Ideal gas equation Ideal gas

    Ideal gas equation: The equation that sums up the ideal gas laws in one simple equation, P V = n R T, Here V is the volume, P is the pressure, n is the

    		•
  • Q : Faradays laws of electrolysis or

    Explain Faradays laws of electrolysis or describe Faradays first law and Faradays second law? Faraday's laws of electrolysis (M. Faraday):

  • Q : Kirchhoffs rules or Loop rule or Point

    Explain Kirchhoff's rules or Kirchhoff's Loop rule and Point rule? Kirchhoff's rules (G.R. Kirchhoff) <

    		•
  • Q : What is curvilinear motion What do you

    What do you mean by the term curvilinear motion? State in brief?

    		•