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NEW GIANT EXTRASOLAR PLANETS
An unusual extrasolar planetary system with massive planets has
been discovered. The star (HD168443) is located approximately 123
light-years away in the direction of the constellation Serpens.
Previous measurements (1999) indicated that HD168443 had at least
one planet. The latest data show that the original planet has a
mass of at least 7.5 Jupiter-masses, and an orbital period of 58
days, placing it closer to its star than Mercury is to our Sun.
The second object has an apparent mass of approximately 17
Jupiter-masses and orbits the star with a period of 4.8 years at
a distance of 3 astronomical units, corresponding to the distance
to the Sun of the asteroid belt in our Solar System. The larger
of the planets is massive enough to be called a brown dwarf star,
and there is currently no explanation of how such a planetary
system could be formed. (Science 25 Jan 01 409:462)
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