--%>

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 Coulombs law Coulomb's law (C.

    Coulomb's law (C. de Coulomb): The basic law for electrostatics, equivalent to Newton's law of universal gravitation. It defines that the force between two point charges is proportional to the arithmetical product of their respective

  • Q : Motion balance principle Explain in

    Explain in detail the motion balance principle

  • Q : What is Reflection law Reflection law :

    Reflection law: For a wave-front intersecting a reflecting surface, the angle of incidence is equivalent to the angle of reflection, in the similar plane stated by the ray of incidence and the normal.

  • Q : Faradays laws of electromagnetic

    Explain Faraday's laws of electromagnetic induction and explain Faraday's first, second and third law of electromagnetic induction? Faraday's laws of electromagnetic in

  • Q : Explain Event horizon Event horizon:

    Event horizon: The radius which a spherical mass should be compressed to in order to convert it into a black hole, or the radius at which the time and space switch responsibilities. Once within the event horizon, it is basically impossible to escape t

  • Q : What do you mean by the term density

    What do you mean by the term density? Briefly explain it.

  • Q : Explain Lagrange points Lagrange points

    Lagrange points: The points in the vicinity of two massive bodies (like the Earth and Moon) with each others' relevant gravities balance. There are five, labeled L1 via L5. L1, L2, and L3 lie all along the centerline among the centers

  • Q : What do you mean by the term cardiac

    What do you mean by the term cardiac output? Briefly explain it.

  • Q : Measure of the force of gravity Briefly

    Briefly explain the measure of the force of gravity on the object?

  • Q : Define Static limit Static limit : The

    Static limit: The distance from a rotating black hole where no spectator can possibly stay at rest (with respect to the far-away stars) since of inertial frame dragging; this area is external of the event horizon, apart from at the poles where it meet