--%>
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 : Atomic model which the Erwin

    Briefly state the atomic model which the Erwin Schrodinger creates?

    		•
  • Q : Explain BCS theory BCS theory -  The

    BCS theory - The theory put forth to elucidate both superconductivity and super fluidity. This suggests that in the superconducting (or super fluid) state electrons form Cooper pairs, where two electrons proceed as a single unit. This takes a non

    		•
  • 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 : Magnetism what's the unit of Curie

    what's the unit of Curie constant and how to calculate Bohr magneton from the plot of 1/Khi vs Temperature(K)?

    		•
  • Q : Define Copernican principle Copernican

    Copernican principle (N. Copernicus): The idea, recommended by Copernicus, that the Sun, not the Earth, is at the center of the earth. We now know that neither idea is accurate (that is, the Sun is not even situated at the center of o

    		•
  • Q : Rest mass energy of the electron What

    What do you mean by the rest mass energy of the electron?

    		•
  • Q : Calculate power consumed : A voltage v

    : A voltage v = 150 + j180 is applied across an impedance and the current flowing is I = 5 - j4 find ? A, impedance . B, resistance. C, reactance. D, power consumed. 

    		•
  • Q : Define Ohm or SI unit of electric

    Ohm: Omega: O (after G. Ohm, 1787-1854) The derived SI unit of electric resistance, stated as the resistance among two points on a conductor whenever a constant potential difference of 1 V generates a current of 1 A in the conductor;

    		•
  • Q : What is Maxwells demon Maxwell's demon

    Maxwell's demon (J.C. Maxwell): A contemplation experiment describing the concepts of entropy. We contain a container of gas that is partitioned into two equivalent sides; each side is in thermal equilibrium with the other. The walls and the separatio

    		•
  • Q : Why tea kettle sing What is the reason

    What is the reason that the tea kettle sing? Briefly state the reason.

    		•