--%>
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 Ideal gas laws or Boyle

    Explain Ideal gas laws or describe Boyle's law or Charle's law and Pressure law: Ideal gas laws: Boyle's law:

    		•
  • Q : What is Roche limit Roche limit : The

    Roche limit: The position about a massive body where the tidal forces due to the gravity of the primary equivalent or exceed the surface gravity of a specified satellite. Within the Roche limit, such a satellite will be interrupted by tides.

    		•
  • Q : Explain Thomson experiment or Kelvin

    Thomson experiment: Kelvin effect (Sir W. Thomson [later Lord Kelvin]): Whenever an electric current flows via a conductor whose ends are maintained at various temperatures, heat is discharged at a rate just about proportional to the

    		•
  • Q : Explain Null experiment Null

    Null experiment: The experiment which, after being performed, yields no outcome. The null experiments are just as significant as non-null experiments; when current theory predicts an observable result (or predicts there must be no observable result),

    		•
  • Q : Explain Rydberg formula Rydberg formula

    Rydberg formula (Rydberg): The formula that explains all of the characteristics of hydrogen's spectrum, comprising the Balmer, Paschen, Lyman, Brackett, and Pfund sequence. For the transition between an electron in

    		•
  • Q : Explain Ohms law Ohm's law (G. Ohm;

    Ohm's law (G. Ohm; 1827): The ratio of the potential difference among the ends of a conductor to the current flowing via it is constant; the constant of proportionality is termed as the resistance, and is distinct for different materials.

    		•
  • Q : What is Lyman series Lyman series: The

    Lyman series: The sequence that explains the emission spectrum of hydrogen whenever electrons are jumping to the ground state. Each and every line is in the ultraviolet.

    		•
  • 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 : Radar gun problem Whenever a radar gun

    Whenever a radar gun states the pitch is 90 miles per hour at what point in the balls travel to home plate is the radar gun evaluating the velocity?

    		•
  • Q : What is Magnetic monopole Magnetic

    Magnetic monopole: The hypothetical particle that comprises sources and sinks of the magnetic field. The magnetic monopoles have never been found, however would only cause pretty minor modifications to the Maxwell's equations. They also appear to be p

    		•