--%>
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 Huygens construction Huygens'

    Huygens' construction: Huygens ‘Principle (C. Huygens): The mechanical propagation of the wave (specially, of light) is equal to supposing that every point on the wave front acts as a point source of the wave emission.

    		•
  • 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 Photovoltaics Photovoltaics (PV)

    Photovoltaics (PV): It transform light directly into electricity. The typical current residential installation of 12m2 could produce around 1,300 kWh pa with a peak of around 1.9kW, though larger and more efficient installations are possibl

    		•
  • Q : Describe Wien displacement law Wien

    Wien displacement law: For a blackbody, the product result of the wavelength corresponding to the maximum radiances and the thermodynamic temperature is constant, then the Wien displacement law constant. As an outcome, as the temperature increases, th

    		•
  • Q : Dielectric Materials Dielectric is a

    Dielectric is a material in which energy can be accumulated. Ideally, it  is  a non-conductor  of  electric  charge  like  insulators, but  an  efficient   supporter  of  electrostatic  fields. The

    		•
  • Q : What is Bode's law Bode's law :

    Bode's law: Titius-Bode law - The mathematical formula that generates, with a fair quantity of accuracy, the semi major axes of the planets in out of order from the Sun. Write down the progression 0, 3, 6, 12, 24,

    		•
  • Q : What is Arago spot What is  Arago

    What is Arago spot? The bright spot which appears in the shadow of a consistent disc being backlit by monochromatic light originating from a point source. &n

    		•
  • Q : Explain Archimedes' principle What is 

    What is Archimedes' principle? A body which is submerged in a fluid is buoyed up by a force equivalent in magnitude to the weight of the fluid which is displaced, and directed upward all along a line via the c

    		•
  • Q : Define Heat pumps Heat pumps move heat

    Heat pumps move heat from one place to another. They work similar to refrigeration. The movement of heat takes energy, either electrical energy as in the use of  vapor compression heat pumps or thermal energy as in the use of absorption heat pump

    		•
  • Q : Blackbody radiation What is Blackbody

    What is Blackbody radiation - The radiation - that is the radiance at specific frequencies all across the spectrum -- generated by a blackbody -- which is, a perfect radiator and absorber of the heat. Physicists had complexity exp

    		•