16 Cygni

Starbox begin
name = 16 CygniStarbox image


caption=16 Cygni A/B on DSS2, 0.3° view Starbox observe 2s
epoch = J2000.0
constell = Cygnus
component1 = 16 Cygni A
ra1 = RA|19|41|48.9535
dec1 = DEC|+50|31|30.217
appmag_v1 = 5.96
component2 = 16 Cygni B
ra2 = RA|19|41|51.9720
dec2 = DEC|+50|31|03.083
appmag_v2 = 6.20Starbox character
class = G1.5Vb / G2.5Vb / M?V
r-i =
v-r =
b-v = 0.64 / 0.66
u-b = 0.19 / 0.20
variable = "None"Starbox astrometry
radial_v=-25.6
prop_mo_ra=-147.75
prop_mo_dec=-158.85
parallax=46.25
p_error=0.50
dist_ly=70.5
dist_pc=21.6
absmag_v=4.29 / 4.53Starbox detail
source =
mass = 1.02 / 0.97
radius = 1.4 / 1.2
gravity =
luminosity = 1.6 / 1.3
temperature = 5825 / 5640
metal = 114% / 123% Sun
rotation = 26.9 / 29.1
age = 10.4×10⁹ / 9.9×10⁹Starbox catalog
names = 16 Cygni A
BD+50°2847, GCTP 4634.00, Gl 765.1 A, HD 186408, HIP 96895, HR 7503, LTT 15750, SAO 31898, Struve 4046A
16 Cygni B
BD+50°2848, Gl 765.1 B, HD 186427, HIP 96901, HR 7504, LTT 15751, SAO 31899, Struve 4046BStarbox reference
Simbad = HD+186408
ARICNS = Starbox reference
Simbad = HD+186427
ARICNS =

16 Cygni is a triple star system approximately 70 light-years away in the constellation of Cygnus. It consists of two Sun-like yellow dwarf stars and a red dwarf. In 1996 an extrasolar planet was discovered in an eccentric orbit around the sunlike star 16 Cygni B.

Distance

The parallax of the two brightest stars were measured as part of the Hipparcos astrometry mission. This yielded a parallax of 46.25 milliarcseconds for 16 Cygni A [cite web|url=http://vizier.u-strasbg.fr/viz-bin/VizieR-S?HIP%2096895|title=HIP 96895|work=The Hipparcos and Tycho Catalogues|publisher=ESA|year=1997|accessmonthday=27 June|accessyear=2006] and 46.70 milliarcseconds for 16 Cygni B. [cite web|url=http://vizier.u-strasbg.fr/viz-bin/VizieR-S?HIP%2096901|title=HIP 96901|work=The Hipparcos and Tycho Catalogues|publisher=ESA|year=1997|accessmonthday=27 June|accessyear=2006] Since the two components are associated, it is reasonable to assume they lie at the same distance, so the different parallaxes are a result of experimental error (indeed, when the associated parallax errors are taken into account, the ranges of the parallaxes overlap). Using the parallax of the A component, the distance is 21.6 parsecs. The parallax of the B component corresponds to a distance of 21.4 parsecs.

Stellar components

16 Cygni is a hierarchial triple system. Stars A and C form a close binary with a projected separation of 73 AU.Raghavan, D. et al. (2006) [http://fr.arxiv.org/abs/astro-ph/0603836 "Two Suns in The Sky: Stellar Multiplicity in Exoplanet Systems"] (preprint)] The orbital elements of the A-C binary are currently unknown. At a distance of 860 AU from A is a third component designated 16 Cygni B. The orbit of B relative to the A-C pair was determined in 1999 and not updated since (as of June 2007): plausible orbits range in period from 18,200 to 1.3 million years, with a semimajor axis ranging from 877 to 15,180 AU. In addition B orbits between 100 and 160 degrees inclination, that is against the A-C pole such that 90 degrees would be ecliptical. [cite journal |url=http://www.journals.uchicago.edu/PASP/journal/issues/v111n757/980185/brief/980185.abstract.html |author=Hauser, H., Marcy, G.|title=The Orbit of 16 Cygni AB|journal=Publications of the Astronomical Society of the Pacific|volume=111|pages=321 – 334|year=1999|doi=10.1086/316328|format=abstract]

Both 16 Cygni A and 16 Cygni B are yellow dwarf stars like our Sun. According to data from the Geneva-Copenhagen survey, both stars have masses similar to the sun. [cite web|url=http://vizier.u-strasbg.fr/viz-bin/VizieR-5?-out.add=.&-source=V/117/table1&recno=13627 |title=Record 13627|work=Geneva-Copenhagen Survey of Solar neighbourhood|author=Nordstrom et al.|year=2004|accessmonthday=4 July|accessyear=2006] [cite web|url=http://vizier.u-strasbg.fr/viz-bin/VizieR-5?-out.add=.&-source=V/117/table1&recno=13631 |title=Record 13631|work=Geneva-Copenhagen Survey of Solar neighbourhood|author=Nordstrom et al.|year=2004|accessmonthday=4 July|accessyear=2006] Age estimates for the two stars vary slightly, but 16 Cygni is likely to be much older than our solar system, at around 10,000 million years old. 16 Cygni C is much fainter than either of these stars, and may be a red dwarf.

Planetary system

In 1996 an extrasolar planet in an eccentric orbit was announced around the star 16 Cygni B. [cite journal | url=http://www.journals.uchicago.edu/doi/full/10.1086/304245 | author=Cochran "et al." | title=The Discovery of a Planetary Companion to 16 Cygni B | journal=The Astrophysical Journal | year=1997 | volume=483 | issue=1 | pages=457–463 | doi=10.1086/304245 ] The planet's orbit takes 798.5 days to complete, with a semimajor axis of 1.68 AU. [cite journal | url=http://www.journals.uchicago.edu/doi/abs/10.1086/504701 | author=Butler "et al." | title=Catalog of Nearby Exoplanets | journal=The Astrophysical Journal| volume=646 | issue=1 | pages=505–522 | year=2006 | doi=10.1086/504701 |format=abstract ( [http://exoplanets.org/planets.shtml web version] )] 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.

There was a METI message sent to the 16 Cygni system. It was transmitted from Eurasia's largest radar — 70-meter 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. [ru icon http://www.cplire.ru/rus/ra&sr/VAK-2004.html]

"For the 16 Cyg B system, only particles inside of about 0.3 AU remained stable [within a million years of formation] , leaving open the possibility of short-period planets". For them, observation rules out any such planet of over a Neptune mass. [cite journal | author=WITTENMYER R., ENDL M., COCHRAN W. & LEVISON H. | year=2007 |title=Dynamical and Observational Constraints on Additional Planets in Highly Eccentric Planetary Systems | journal=Astronomical Journal | volume=134 | url=http://arxiv.org/abs/0706.1962v1 | page=1276]

PlanetboxOrbit
exoplanet = b
mass = >1.68 ± 0.15
period = 798.5 ± 1.0
semimajor = 1.681 ± 0.097
eccentricity = 0.681 ± 0.017

See also

* 61 Cygni
* 83 Leonis
* 54 Piscium (HD 3651)
* HD 20782
* HD 80606
* HD 89744
* HD 222582

References

External links

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