Planetary System
In 1996 an extrasolar planet in an eccentric orbit was announced around the star 16 Cygni B. The planet's orbit takes 798.5 days to complete, with a semimajor axis of 1.68 AU. Like the majority of known extrasolar planets, 16 Cygni Bb was detected by measuring the radial velocity of its parent star, which only gives a lower limit on the mass: in this case, about 1.68 times that of Jupiter. "For the 16 Cyg B system, only particles inside of about 0.3 AU remained stable, leaving open the possibility of short-period planets". For them, observation rules out any such planet of over a Neptune mass.
There was a METI message sent to the 16 Cygni system. It was transmitted from Eurasia's largest radar – 70-meter (230-foot) Eupatoria Planetary Radar. The message was named Cosmic Call 1, it was sent on May 24, 1999, and it will arrive at 16 Cygni in November 2069.
The 16 Cygni system is within the field of view of the now-operational Kepler Mission planet-hunter spacecraft.
| Companion |
Mass | Semimajor axis |
Orbital period |
Eccentricity | Radius |
|---|---|---|---|---|---|
| b | ≥1.68 ± 0.15 MJ | 1.681 ± 0.097 | 798.5 ± 1.0 | 0.681 ± 0.017 | — |
Read more about this topic: 16 Cygni
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