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2M1207





2M1207
A brown dwarf around which orbits the first extrasolar planet ever to be directly photographed. 2M1207 (full catalog designation: 2MASSWJ1207334-393254) lies in the constellation Hydra at a distance of 228 light-years. Its companion planet, known as 2M1207b, is about five times the size of Jupiter and is orbiting at a distance nearly twice as far as Neptune is from our Sun.

Given the rather unusual properties of the 2M1207 system, the giant planet most probably did not form like the planets in our solar system. Instead it may have formed the same way our Sun formed, by gravitational collapse of a cloud of gas and dust. A team of European and American scientists working with the Very Large Telescope of the European Southern Observatory initially released a picture showing the planet in September 2004. Further images, taken in 2005, confirmed the nature of the object.


Host star
distance 228 light-years (70 pc)
spectral type M8
apparent magnitude 13
mass (Sun = 1) 0.025
position RA 12h 07m 33.4s; Dec -39° 32' 54"


Planet
mass (Jupiter = 1) 5±2
semimajor axis 55 AU (8.3 billion km, 5.1 million mi.)
orbital period > 2450 years
eccentricity ?
year of discovery 2005
discovery Chauvin et al; VLT
method of discovery direct imaging


References

  1. Chauvin G., Lagrange A.-M., Dumas C., Zuckerman B., Mouillet D., Song I., Buezit J.-L. & Lowrance, P., 2005. "Confirmation of a Giant Planet Companion to the brown dwarf 2MASSWJ1207334-393254." Astron. & Astrophys., accepted.
  2. Chauvin G., Lagrange A.-M., Dumas C., Zuckerman B., Mouillet D., Song I., Buezit J.-L. & Lowrance, P., 2004 "A giant planet candidate near a young brown dwarf." Astron. & Astrophys., 425, L29.

Related categories

   • EXTRASOLAR PLANETS AND SUBSTELLAR OBJECTS
   • NOTABLE STARS