Astronomy:HD 69830
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Puppis |
| Right ascension | 08h 18m 23.94697s[1] |
| Declination | −12° 37′ 55.8172″[1] |
| Apparent magnitude (V) | +5.98[2] |
| Characteristics | |
| Spectral type | G8V[3] |
| U−B color index | 0.33[2] |
| B−V color index | 0.75[2] |
| V−R color index | 0.40 |
| R−I color index | 0.36 |
| Variable type | none |
| Astrometry | |
| Radial velocity (Rv) | 30.09±0.12[1] km/s |
| Proper motion (μ) | RA: 278.790[1] mas/yr Dec.: −987.829[1] mas/yr |
| Parallax (π) | 79.4953 ± 0.0400[1] mas |
| Distance | 41.03 ± 0.02 ly (12.579 ± 0.006 pc) |
| Absolute magnitude (MV) | 5.47 ± 0.01[4] |
| Details | |
| Mass | 0.89 ± 0.03[5] M☉ |
| Radius | 0.905 ± 0.019[3] R☉ |
| Luminosity | 0.622 ± 0.014[3] L☉ |
| Surface gravity (log g) | 4.53[6] cgs |
| Temperature | 5,394 ± 62[3] K |
| Metallicity [Fe/H] | −0.04 ± 0.03[3] dex |
| Rotation | 35.1 ± 0.8 days[7] |
| Rotational velocity (v sin i) | 0.8±0.5[3] km/s |
| Age | 10.6 ± 4[3] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
| ARICNS | data |
| Extrasolar Planets Encyclopaedia | data |
HD 69830 (285 G. Puppis) is a yellow dwarf star located 41.0 light-years (12.6 parsecs) away in the constellation of Puppis. In 2005, the Spitzer Space Telescope discovered a narrow ring of warm debris orbiting the star.[10] The debris ring contains substantially more dust than the Solar System's asteroid belt. In 2006, three extrasolar planets with minimum masses comparable to Neptune were confirmed in orbit around the star, located interior to the debris ring.[11]
Distance and visibility
HD 69830 is a main sequence star of spectral type G8V. It has about 86% of the Sun's mass, 90% of its radius, 62% of its luminosity, and 89% of its iron abundance. The star's age has been estimated at 10.6 ± 4 billion years. HD 69830 is located about 40.7 light-years from the Sun, lying in the northeastern part of the constellation of Puppis (the Poop Deck). It can be seen east of Sirius, southwest of Procyon, northeast of Delta Canis Majoris, and north of Zeta Puppis.
Planetary system
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | ≥10.1+0.38 −0.37 M⊕ |
0.0764±0.0017 | 8.66897±0.00028 | 0.128±0.028 | — | — |
| c | ≥12.09+0.55 −0.54 M⊕ |
0.181±0.004 | 31.6158±0.0051 | 0.03±0.027 | — | — |
| d | ≥12.26+0.89 −0.88 M⊕ |
0.622±0.014 | 201.4±0.4 | 0.08±0.071 | — | — |
| Asteroid belt | 0.93–1.16 AU | — | — | |||
Planets
On May 17, 2006, a team of astronomers using the European Southern Observatory's (ESO) HARPS spectrograph on the 3.6-metre La Silla telescope in the Atacama desert, Chile , announced the discovery of three extrasolar planets orbiting the star. With minimum masses between 10 and 18 times that of the Earth, all three planets are presumed to be similar to the planets Neptune or Uranus.[11] (As of 2011), no planet with more than half the mass of Jupiter had been detected within three astronomical units of HD 69830.
The star rotates at an inclination of 13+27−13 degrees relative to Earth.[7] It has been assumed that the planets share that inclination.[13] However b and c are "hot Neptunes", and outside this system several are now known to be oblique relative to the stellar axis.[14]
The outermost planet discovered appears to be within the system's habitable zone, where liquid water would remain stable (more accurate data on the primary star's luminosity will be required to know for sure where the habitable zone is). HD 69830 is the first extrasolar planetary system around a Sun-like star without any known planets comparable to Jupiter or Saturn in mass.[11]
The planetary parameters were updated in 2023.[5]
Debris disk
In 2005, the Spitzer Space Telescope detected a debris disk in the HD 69830 system consistent with being produced by an asteroid belt twenty times more massive than that in our own system. The belt was originally thought to be located inside an orbit equivalent to that of Venus in the Solar System, which would place it between the orbits of the second and third planets. The disk contains sufficient quantities of dust that the nights on any nearby planets would be lit up by zodiacal light 1000 times brighter than that seen on Earth, easily outshining the Milky Way.
Further analysis of the spectrum of the dust revealed that it is composed of highly processed material, likely derived from a disrupted C-type asteroid of at least 30 km radius which contained many small olivine-rich (rocky) and once-wet grains which would not survive at close distances to the star. Instead, it seems more likely that the asteroid belt producing the dust is located outside the orbit of the outermost planet, around 1 AU from the star. This region contains the 2:1 and 5:2 mean motion resonances with HD 69830 d.[12]
Gallery
A comparison between the night sky of Earth and a planet of HD 69830.
The orbits of the planets of HD 69830 and the debris disk.
In fiction
- In the first-person shooter videogame franchise Halo, the homeworld of the Kig-Yar species is a moon orbiting within the HD 69830 system, with the system being known as "Y'Deio" the third planet in the system called "Chu'ot" and their homeworld being called Eayn.
See also
- HD 169830
- HD 40307
- HD 60532
- List of extrasolar planets
- List of star systems within 40–45 light-years
References
- ↑ 1.0 1.1 1.2 1.3 1.4 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940 Gaia DR3 record for this source at VizieR.
- ↑ 2.0 2.1 2.2 Mermilliod, J.-C. (1986), "Compilation of Eggen's UBV data, transformed to UBV (unpublished)", Catalogue of Eggen's UBV Data. SIMBAD, Bibcode: 1986EgUBV........0M.
- ↑ 3.0 3.1 3.2 3.3 3.4 3.5 3.6 Tanner, Angelle et al. (February 2015), "Stellar Parameters for HD 69830, a Nearby Star with Three Neptune Mass Planets and an Asteroid Belt", The Astrophysical Journal 800 (2): 5, doi:10.1088/0004-637X/800/2/115, 115, Bibcode: 2015ApJ...800..115T.
- ↑ Holmberg, J. et al. (2009). "The Geneva-Copenhagen survey of the solar neighbourhood. III. Improved distances, ages, and kinematics". Astronomy and Astrophysics 501 (3): 941–947. doi:10.1051/0004-6361/200811191. Bibcode: 2009A&A...501..941H. http://www.aanda.org/articles/aa/full_html/2009/27/aa11191-08/aa11191-08.html.Vizier catalog entry
- ↑ 5.0 5.1 5.2 Laliotis, Katherine et al. (February 2023). "Doppler Constraints on Planetary Companions to Nearby Sun-like Stars: An Archival Radial Velocity Survey of Southern Targets for Proposed NASA Direct Imaging Missions". The Astronomical Journal.
- ↑ Ramírez, I. et al. (February 2013), "Oxygen abundances in nearby FGK stars and the galactic chemical evolution of the local disk and halo", The Astrophysical Journal 764 (1): 78, doi:10.1088/0004-637X/764/1/78, Bibcode: 2013ApJ...764...78R.
- ↑ 7.0 7.1 Simpson, E. K. et al. (November 2010), "Rotation periods of exoplanet host stars", Monthly Notices of the Royal Astronomical Society 408 (3): 1666–1679, doi:10.1111/j.1365-2966.2010.17230.x, Bibcode: 2010MNRAS.408.1666S.
- ↑ "Uranometria Argentina". http://www.uranometriaargentina.com/.
- ↑ "HD 69830". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+69830.
- ↑ Beichman, C. A. et al. (2005). "An Excess Due to Small Grains around the Nearby K0 V Star HD 69830: Asteroid or Cometary Debris?". The Astrophysical Journal 626 (2): 1061–1069. doi:10.1086/430059. Bibcode: 2005ApJ...626.1061B.
- ↑ 11.0 11.1 11.2 11.3 Lovis, Christophe et al. (2006). "An extrasolar planetary system with three Neptune-mass planets". Nature 441 (7091): 305–309. doi:10.1038/nature04828. PMID 16710412. Bibcode: 2006Natur.441..305L. http://obswww.unige.ch/~pernier/publications-www/articles-pdf-ps/2006Natur.441..305L.pdf. Retrieved 2013-11-22.
- ↑ 12.0 12.1 Lisse, C. M. et al. (2007). "On the Nature of the Dust in the Debris Disk Around HD 69830". The Astrophysical Journal 658 (1): 584–592. doi:10.1086/511001. Bibcode: 2007ApJ...658..584L.
- ↑ "hd_69830_b". Extrasolar Planets Encyclopaedia. https://exoplanet.eu/catalog/hd_69830_b--326/.
- ↑ Roberto Sanchis-Ojeda; Josh N. Winn; Daniel C. Fabrycky (2012). "Starspots and spin-orbit alignment for Kepler cool host stars". Astronomische Nachrichten 334 (1–2): 180–183. doi:10.1002/asna.201211765. Bibcode: 2013AN....334..180S.
External links
- Clavin, Whitney (2005-04-20). "NASA's Spitzer Telescope Sees Signs of Alien Asteroid Belt". NASA. Spitzer Space Telescope. http://www.spitzer.caltech.edu/Media/releases/ssc2005-10/release.shtml.
- "HD 69830 / HR 3259". SolStation. http://www.solstation.com/stars2/hd69830.htm.
- "Notes for star HD 69830". Extrasolar Planets Encyclopaedia. http://exoplanet.eu/star.php?st=HD+69830. Retrieved 2008-06-13.
- Than, Ker (2006-05-17). "Planets Found in Potentially Habitable Setup". SPACE.com. http://www.space.com/scienceastronomy/060517_netpune_planets.html.
- "Trio Of Neptunes And Their Belt". SpaceDaily. 2006-05-18. http://www.spacedaily.com/reports/Trio_Of_Neptunes_And_Their_Belt.html.
- Extrasolar Planet Interactions by Rory Barnes & Richard Greenberg, Lunar and Planetary Lab, University of Arizona
Coordinates: 
08h 18m 23.9s, −12° 37′ 55.0″
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