--%>
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 : What is Cherenkov radiation Cherenkov

    Cherenkov radiation (P.A. Cherenkov): The radiation emitted by a huge particle which is moving faster than light in the medium via which it is travelling. No particle can travel faster than the light in vacuum, however the speed of light in other medi

    		•
  • Q : Physics Assignement complete assignment

    complete assignment with clear solution and explanation

    		•
  • Q : What is Pfund series Pfund series: The

    Pfund series: The series that explains the emission spectrum of hydrogen whenever the electron is jumping to the fifth orbital. Each line is in the infrared part of the spectrum.

    		•
  • Q : Define Planck constant Planck constant

    Planck constant: h: The basic constant equivalent to the ratio of the energy of a quantum of energy to its frequency. This is the quantum of action. This has the value 6.626 196 x 10-34 J s.

    		•
  • Q : Explain Einstein field equation

    Einstein field equation: The cornerstone of Einstein's general theory of relativity, associating the gravitational tensor G to the stress-energy tensor T by the simple equation: G = 8 pi T<

    		•
  • Q : Anthropic principle What is  Anthropic

    What is Anthropic principle? Explain Weak anthropic principle and Strong anthropic principle?

    Q : Brief note on the classification of

    Write down a brief note on the classification of Alloys?

    		•
  • 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 : What is Kerr effect Kerr effect (J.

    Kerr effect (J. Kerr; 1875): The capability of certain substances to refract light waves in a different way whose vibrations are in dissimilar directions whenever the substance is located in an electric field.

    		•
  • 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

    		•