HD 4208 b

HD 4208 b is an extrasolar planet orbiting the yellow dwarf HD 4208 . Due to its mass , it is assumed that it is a gas planet .

discovery

The planet was discovered by the California and Carnegie Planet Search Team using the Keck Telescope using the radial velocity method. The discovery was published by Steven Vogt , R. Paul Butler , Geoffrey Marcy, and others in 2001 .

Track properties

The planet orbits its star at a distance of approximately 1.65 astronomical units . Its orbit roughly corresponds to that of Mars around the Sun in terms of distance . The eccentricity is very small at about 0.05 and thus the orbit is almost circular. The orbital period is about 800 earth days.

Physical Properties

The planet probably has a slightly smaller mass than Jupiter , although only a minimum mass can be determined. The minimum mass is around 0.80 Jupiter masses (approx. 260 earth masses ).

According to estimates, the temperature on the planet's surface is around 140 Kelvin (- 130 ° C), like on Saturn .

Since temperatures are likely to be too low both on the planet itself and on any moons that may be present, there is probably only a chance for life under subterranean oceans or oceans covered by an ice sheet. Jupiter's moon Europa probably has such oceans. The future must show whether this is the case and whether life is even possible there .

Web links

• The exoplanet in the "Encyclopedia of Extrasolar Planets"
• The planet at Planet.ch ( Memento from October 15, 2012 in the Internet Archive )

swell

• S. Vogt, P. Butler, G. Marcy, D. Fischer, D. Pourbaix, K. Apps and G. Laughlin: Ten Low Mass Companions from the Keck Precision Velocity Survey. ApJ., (2001). 568, 352.
• RP Butler et al .: Catalog of Nearby Exoplanets. The Astrophysical Journal, (2006). 646: 505-522. Abstract .