--%>
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 : Plasma globe AD advantages and

    advantages and disadvantages of a plasma globe

    		•
  • Q : Steps to the scientific notation

    Illustrate the steps to the scientific notation? Briefly illustrate the steps.

    		•
  • Q : Weights in pounds of the liquid gallons

    Write down the weights in pounds of the liquid gallons? Briefly describe it.

    		•
  • Q : Candela Candela : The basic SI unit of

    Candela: The basic SI unit of luminous intensity stated as the luminous intensity in a given direction of a source which emits monochromatic photons of frequency 540 x 1012 Hz and encompasses a radiant intensity in the direction of 1/683 W/

    		•
  • Q : Procedure to define the Specific Gravity

    Briefly explain the procedure to define the Specific Gravity?

    		•
  • Q : Does solar radiation encompass a

    Does solar radiation encompass a complete spectrum of all the forms of electromagnetic radiation?

    		•
  • Q : Define Equivalence principle

    Equivalence principle: The fundamental postulate of Sir Einstein’s general theory of relativity that posits that acceleration is basically indistinguishable from the gravitational field. In another words, when you are in an elevator that is utte

    		•
  • Q : Define Mole or SI unit of substance

    Mole: mol: The basic SI unit of substance, stated as the quantity of substance which contains as many elementary units (that is, atoms, molecules, ions, and so forth) as there are atoms in 0.012 kg of carbon-12.

    		•
  • Q : Define Dirac constant Dirac constant :

    Dirac constant: Planck constant, modified form; hbar Sometimes more suitable form of the Planck constant, stated as: hbar = h/(2 pi)

    		•
  • Q : Define Superconductivity

    Superconductivity: The phenomenon by which, at adequately low temperatures, a conductor can conduct the charge with zero (0) resistance. The current theory for describing superconductivity is the BCS theory.

    		•