--%>
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 : Calculating current in magnetically

    For the magnetically coupled circuit in Figure a, calculate I1 and I2. If the dotted terminals in are changed so that the circuit now becomes that in Figure b, re-calculate I1 and I2.

  • Q : Definition of Pascals principle Briefly

    Briefly state the definition of Pascal’s principle?

    		•
  • Q : Simulation using VMD and NMD programes

    I need the homework to be finished in five days. and could you please tell me if you are familiar with VMD and NMD simulation programs or not? I will send you some docments that I think it could help to solve the homework questions. But please send me an email so I can attached both files. all b

    		•
  • Q : Explain Fizeau method Fizeau method (A.

    Fizeau method (A. Fizeau, 1851): One of the primary truthfully relativistic experiments intended to compute the speed of light. Light is passed via a spinning cog-wheel driven by running water, is reflected off a far-away mirror, and

    		•
  • Q : Current through resistors How do I find

    How do I find out a maximum current flowing through a resistor with just the resistance of the resistor and it's power rating?

    		•
  • Q : Define Faint Faint , young sun paradox

    Faint, young sun paradox: The theories of stellar evolution point out that as stars mature on the main series, they grow gradually hotter and brighter; computations propose that at as regards the time of the formation of Earth, the Su

    		•
  • Q : Define Faraday constant Faraday

    Faraday constant: F (M. Faraday): The electric charge fetched by one mole of electrons or singly-ionized ions. It is equivalent to the product result of the Avogadro constant and the absolute value of the charge on an electron; this i

    		•
  • Q : Define Zeeman Effect or Zeeman line

    Zeeman Effect: Zeeman line splitting (P. Zeeman; 1896): Zeeman Effect is the splitting of lines in a spectrum whenever the source is exposed to the magnetic field.

    		•
  • Q : Define Hertz or SI unit of frequency

    Define Hertz or SI unit of frequency: Hertz: Hz (after H. Hertz, 1857-1894): The derived SI unit of frequency, stated as a frequency of 1 cycle per s; it therefore has units of s-1.

    		•
  • Q : Define Laue pattern Laue pattern (M.

    Laue pattern (M. von Laue): The pattern generated on a photographic film whenever high-frequency electromagnetic waves (like x-rays) are fired at the crystalline solid.

    		•