Planetary system

A planetary system is a collection of massive bodies, which - bound by the gravitational force - to move at least a central star. The largest of these bodies - as long run in its interior no nuclear fusion processes - in our planetary system ( with the central star 'Sun' ) as " planets ", otherwise as " extrasolar planets " or " exoplanets ". Massive body without a central star (s ) are called " planetary mass objects ".

Details

The best-known planetary system is the sun, the solar system, which was the only known occurrence of a system of arranged around a central star planetary bodies until the discovery of the first extrasolar planet in 1992.

By March 2003, the star planets have been discovered within 100 parsecs by seven percent. In November 2013 over 1000 planets in 790 extrasolar systems were known, of which 175 with 2 to 7 planets. The system to Kepler -90 has at least seven exoplanets.

There are also systems in which planets orbiting a binary star system (English circumbinary ). Examples are PH1, Kepler -47 and Kepler - 16b.

Known planetary systems

Among the most important planetary systems, insofar as they are known to science, including among others, in addition to the solar system:

  • 47 Ursae Majoris
  • 55 Cancri
  • Gliese 581 ( with the Earth-like planet Gliese 581 c )
  • Gliese 876
  • HD 37124
  • HD 69830
  • My Arae
  • PSR B1257 12
  • Upsilon Andromedae
  • Kepler -90 ( system has similarities to the solar system, planets 7 )
Kepler-90 Kepler-47 Protoplanetary disk
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