--%>
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 : Explain Daltons law of partial pressures

    Dalton's law of partial pressures (J. Dalton): The net pressure of a mixture of ideal gases is equivalent to the sum of the partial pressures of its components; which is the sum of the pressures which each component would exert when it were present al

    		•
  • Q : What is Complementarity principle

    Complementarity principle (N. Bohr): The principle that a specified system can’t exhibit both wave-like behavior and particle-like behavior at similar time. That is, some experiments will reveal the wave-like nature of a system,

    		•
  • Q : Ampere's law Explain  Ampere's law?  

    Explain Ampere's law?   Ampere's law (A.M. Ampere):

  • Q : Why tea kettle sing What is the reason

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

    		•
  • Q : Explain Casimir effect Casimir effect

    Casimir effect (Casimir): The quantum mechanical effect, where two very big plates positioned close to each other will experience an attractive force, in the nonattendance of other forces. The cause is implicit particle-antiparticle p

    		•
  • Q : Explain Faradays law Faraday's law (M.

    Faraday's law (M. Faraday): The line integral of the electric field about a closed curve is proportional to the instant time rate of change of the magnetic flux via a surface bounded by that closed curve; in the differential form,

    		•
  • Q : Development of Missile technology Name

    Name the women scientist who played the essential role in the development of Missile technology of India and is nick named as the ‘Missile Woman’?

    		•
  • 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 : Problem on synchronous TDM We require

    We require using synchronous TDM and joining 20 digital sources, each of 100 Kbps. Each and every output slot carries 1 bit for each digital source, however one extra bit is added up to each frame for synchronization.

    Q : Scanning electron and transmission

    Give one benefit of a scanning electron microscope over the transmission electron microscope? Briefly explain it.

    		•