HD 221287

Starbox short
name = HD 221287
epoch = J2000.0
constell = Tucana
ra = RA|23|31|20.339
dec = DEC|-58|12|35.04
appmag_v = +7.82
absmag_v = +4.20
dist_ly = 172.5
dist_pc = 52.9
spectral = F7V
names = CD-58°8579, HIP 116084, SAO 247912
Simbad = HD+221287

HD 221287 is a yellow-white main-sequence star approximately 173 light years away in the constellation of Tucana. It has an apparent magnitude of 7.82 and absolute magnitude of 4.20. This star is also named HIP 116084.

Planetary system

On March 5, 2007, the astronomer Dominique Naef used the HARPS spectrograph to uncover HD 221287 b (among others). [Cite journal | url=http://www.aanda.org/articles/aa/abs/2007/29/aa7361-07/aa7361-07.html | title=The HARPS search for southern extra-solar planets IX. Exoplanets orbiting HD 100777 , HD 190647 , and HD 221287 | author=Naef "et al." | journal=Astronomy and Astrophysics | year=2007 | volume=470 | issue=2 | pages=721–726 | 10.1051/0004-6361:20077361 | format=abstract ( [http://arxiv.org/abs/0704.0917 web preprint] )] Using the amplitude from observations with HARPS, he calculated a minimum mass of 3.12 times that of Jupiter, making this a superjovian. This planet orbits 25% further from the star than Earth to the Sun with a low eccentricity.

There could be an Earth sized planet in its Trojan field. [cite journal |journal=Astronomy & Astrophysics |DOI=10.1051/0004-6361:20077994 | volume=474|page=1023-1029 |url=http://adsabs.harvard.edu/abs/2007A%26A...474.1023S |title=Survey of the stability region of hypothetical habitable Trojan planets |author=R. Schwarz, R. Dvorak, Á. Süli, and B. Érdi |month=November |year=2007: HD 93083, HD 17051, HD 28185, HD 27442, HD 188015, HD 99109, HD 221287]

PlanetboxOrbit
exoplanet = b
mass = >3.12 ± 0.78
period = 456.1 ± 6.5
semimajor = 1.25 ± 0.04
eccentricity = 0.08 ± 0.11

References

External links

*cite web|url=http://exoplanet.eu/star.php?st=HD+221287|title=Notes for star HD 221287|work=The Extrasolar Planets Encyclopaedia|accessdate=2008-07-21