--%>
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 : 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 : What is Curie constant and Curies law

    What is Curie constant and Curies law? Curie constant: C (P. Curie): The characteristic constant, dependent on the material in question that points out the proportionality among its susceptibility

    		•
  • Q : Define Universal constant of gravitation

    Universal constant of gravitation: G The constant of proportionality in the Newton’s law of universal gravitation and that plays a comparable role in Sir Einstein's general relativity. This is equivalent to the 6.672 x 10-1

    		•
  • 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 : Define Compton Effect Compton Effect

    Compton Effect (A.H. Compton; 1923): The effect which describes those photons (that is the quantum of electromagnetic radiation) has momentum. The photon fired at a stationary particle, like an electron, will communicate momentum to t

    		•
  • 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

    		•
  • Q : Describe the term Specular Reflection

    Describe briefly the term Specular Reflection?

    		•
  • Q : Explain Twin paradox Twin paradox: One

    Twin paradox: One of the most well-known "paradoxes" in history, predicted by Sir Einstein's special theory of relativity. It takes two twins, born on similar date on Earth. One, Albert, leaves home for a trip about the Universe at very high speeds (v

    		•
  • Q : Non-Parametric Tests Activity

    Activity 9:   Non-Parametric Tests    4Non-Parametric Tests While you have learned a number of parametric statistical techniques, you are also aware that if the assumptions related to

    		•
  • Q : Define Newton or SI unit of force

    Newton: N (after Sir I. Newton, 1642-1727): The derived SI unit of force, stated as the force needed to give a mass of 1 kg of an acceleration of 1 m/s2; it therefore has units of kg m/s2.

    		•