HD 210277

Starbox begin
name=HD 210277 Starbox observe
epoch=J2000
ra=22^h 09^m 29.8657^s
dec= -07° 32′ 55.155″
appmag_v=6.63
constell=Aquarius Starbox character
class=G0V
b-v=0.773
u-b=0.43
variable= Starbox astrometry
radial_v=-24.1
prop_mo_ra=85.48
prop_mo_dec=-449.83
parallax=46.97
p_error=0.79
absmag_v=7.34 Starbox detail
mass=1,09
radius=1.1 ± 0.05
luminosity=1,2 | temperature=5532 ± 14
metal=0.19 ± 0.04 | rotation=
age=6.93 G
rotational_velocity = Starbox catalog
names=NLTT 53073, HIC 109378, SAO 145906, BD-08° 5818, GJ 848.4, HIP 109378, Ci 20 1339, GJ 9769, LTT 8887, SPOCS 960, GC 30991, HD 210277, PLX 5356, uvby98 100210277, GCRV 13920, HERZ 16289, PPM 206033, YZ 97 7945. Starbox reference
Simbad=HD+210277
ARICNS =

HD 210277 is a 7th magnitude star in the constellation Aquarius. It is a yellow dwarf star (spectral type G0V) like our Sun. It has a mass around 0.92 times that of our Sun and is estimated to be around 12 billion years old [ cite journal | url=http://www.journals.uchicago.edu/doi/full/10.1086/311847 | author=Gonzalez "et al." | title=Parent Stars of Extrasolar Planets. IV. 14 Herculis, HD 187123, and HD 210277 | journal=Astrophysical Journal | volume=511 | year=1999 | pages=L111–L114 | doi=10.1086/311847 ] . Since its distance is about 69 light years, it is not visible to the unaided eye. With binoculars it is easily visible.

The star has a massive extrasolar planet orbiting it. Also, in 1999 the discovery of a circumstellar disk was announced by T. E. Trilling et al. based on observations in infrared wavelengths. The disk is probably similar to the Kuiper belt in our Solar system.

__TOC__

HD 210277 b

Planetbox begin
name = HD 210277 b [cite journal | url=http://www.journals.uchicago.edu/doi/full/10.1086/504701 | author=Butler "et al." | title=Catalog of Nearby Exoplanets | journal=The Astrophysical Journal | volume=646 | pages=505 – 522 | year=2006 | doi=10.1086/504701 ( [http://exoplanets.org/planets.shtml web version] )] Planetbox orbit
semimajor = 1,138 ± 0.066
eccentricity = 0.476 ± 0.017
period = 442.19 ± 0.50
ang_dist = 50
long_peri = 119.1 ± 2.8
t_peri = 2,450,104.3 ± 2.6
semi-amp = 38.94 ± 0.75
semimajor_gigameter =
periastron = 0,596312
periastron_gigameter =
apastron = 1,679688
apastron_gigameter =
period_year = 1.21
period_megasecond = Planetbox character
mass = >1.29 ± 0.11
radius=1.004 [Estimated [http://www.extrasolar.net/planettour.asp?StarCatId=normal&PlanetId=13 §] ]
density=
gravity=31.755257573452
temperature=237
mass_earth =409.962
gravity_earth =3.238135
insolation =
insolation_earth =
radius_megameter =
mass_wekagram =
radius_earth =11.23951 Planetbox discovery
discovery_date = 1998
discoverers = Marcy et al.
California and
Carnegie Planet Search
flag|USA
discovery_location = [http://exoplanets.org/esp/upsandb/upsandb.shtml exoplanets.org]
discovery_method = Radial velocity
discovery_status=Published Planetbox catalog
names=HD 210277 bPlanetbox reference
star=HD+210277
planet=b

HD 210277 b was discovered in 1998 by the California and Carnegie Planet Search team using the highly successful radial velocity method. The planet is at least 24% more massive than Jupiter. The mean distance of the planet from the star is slightly more than Earth's distance from the Sun. However, the orbit is very eccentric, so at periastron this distance is almost halved, and at apastron it is as distant as Mars is from the Sun [ cite journal | url=http://www.journals.uchicago.edu/doi/full/10.1086/307451 | author=Marcy "et al." | title=Two New Candidate Planets in Eccentric Orbits | journal=The Astrophysical Journal | year=1999 | volume=520 | issue=1 | pages=239–247 | doi=10.1086/307451 ] .

In 2000 group of scientists proposed, based on preliminary data from the "Hipparcos" astrometrical satellite, that the planet would have an inclination of 175.8° and a true mass of 18 times Jupiter making it a brown dwarf instead of a planet [cite journal | url=http://www.journals.uchicago.edu/doi/full/10.1086/318927 | author=Han "et al." | title=Preliminary Astrometric Masses for Proposed Extrasolar Planetary Companions | journal=The Astrophysical Journal Letters | year=2001 | volume=548 | issue=1 | pages=L57–L60 | doi=10.1086/318927 ] . However these measurements were later proved useful only for upper limits of inclination; [cite journal | url=http://adsabs.harvard.edu/abs/2001A%26A...372..935P | title=Screening the Hipparcos-based astrometric orbits of sub-stellar objects | author=Pourbaix, D. and Arenou, F.| journal=Astronomy and Astrophysics | volume=372 | pages=935–944 | year=2001 | doi=10.1051/0004-6361:20010597 ] worthless for HD 192263 b, and for 55 Cancri c and upsilon Andromedae d they contradicted measured inclinations of other planets in their systems. If the planet orbits in the same plane as the circumstellar disk, which seems a plausible assumption, it would have an inclination of 40° and an absolute mass of 2.2 times Jupitercite journal | url=http://www.journals.uchicago.edu/doi/full/10.1086/308280 | author=Trilling "et al." | title=Circumstellar Dust Disks around Stars with Known Planetary Companions | journal=The Astrophysical Journal | volume=529 | year=2000 | issue=1 | pages=499–505 | doi=10.1086/308280 ] .

HD 210277 dust disk

A dust disk around the star HD 210277, similar to that produced by the Kuiper Belt in our solar system was imaged in 1999. It lies between 30 and 62 AU from the star and is estimated to be between 50 and 80 times as massive as our solar system's Kuiper Belt.

References

* [http://www.extrasolar.net/curves/graph_HD210277.jpgPhase Orbital HD 210277]

External links

* [http://www.extrasolar.net Extrasolar Visions] [http://www.extrasolar.net/planettour.asp?StarCatId=normal&PlanetId=13 entry]
* [http://home.xtra.co.nz/hosts/Wingmakers/HD%20210277.html HD 210277]
* [http://exoplanets.org/esp/hd210277/hd210277.shtml The Planet Around HD 210277]
* [http://jumk.de/astronomie/img/hd-210277.jpgImage HD 210277]
* [http://jumk.de/astronomie/exoplanets/hd-210227.shtml jumk.de]
* [http://planetquest1.jpl.nasa.gov/atlas/atlas_skymap.cfm?Planet=125 Location]
* [http://www.alcyone.de/cgi-bin/search.pl?object=HR8734 HR 8734]
* [http://media4.obspm.fr/exoplanets/base/planete.php?etoile=HD+210277&planete=b Simulation Exoplanets]