  | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Eridanus |
| Right ascension | 01h 42m 29.3145s[1] |
| Declination | −53° 44′ 26.991″[1] |
| Apparent magnitude (V) | 5.52[2] |
| Characteristics | |
| Spectral type | F9V[3] |
| B−Vcolor index | 0.551[2] |
| Astrometry | |
| Radial velocity (Rv) | 27.64(12)[1] km/s |
| Proper motion (μ) | RA: 166.041(34)mas/yr[1] Dec.: −105.496(46)mas/yr[1] |
| Parallax (π) | 57.6409±0.0453 mas[1] |
| Distance | 56.58 ± 0.04 ly (17.35 ± 0.01 pc) |
| Absolute magnitude (MV) | 4.32 |
| Details | |
| Mass | 1.11 ± 0.02[3] M☉ |
| Radius | 1.10 ± 0.02[3] R☉ |
| Luminosity | 1.41[3] L☉ |
| Temperature | 6,218 ± 20[3] K |
| Metallicity [Fe/H] | 0.00 ± 0.01[3] dex |
| Rotation | 10 ± 3[3] |
| Rotational velocity (v sin i) | 4.9[3] km/s |
| Age | 1.4 ± 0.9[3] Gyr |
| Other designations | |
| q1 Eridani,5 G. Eridani,CPD−54°365,GJ 3109,HIP 7978,HR 506,SAO 232501[4] | |
| Database references | |
| SIMBAD | data |
HD 10647 (q1 Eridani) is a 6th-magnitudeyellow-white dwarfstar, 57light-years away in theconstellation ofEridanus. The star is visible to the unaided eye under very dark skies. It is slightly hotter andmore luminous than theSun, and at 1.75 billion years old, it is also younger. Anextrasolar planet was discovered orbiting this star in 2003.
![Millimetre image of the disk from the REASONS survey[5]](/mt/?noimg=&dark=on&url=http%3a%2f%2fwww.wikipedia.org%2fwiki%2fFile%3aThe_74_exocomet_belts_imaged_by_ALMA%25E2%2580%2599s_REASONS_survey%2c_showing_belts_of_all_shapes%2c_sizes_and_ages_(REASONS_comboplot_full_nonames).jpg)
In 2003,Michel Mayor's team announced the discovery of a new planet,HD 10647 b, in Paris at the XIX IAP ColloquiumExtrasolar Planets: Today & Tomorrow*[1]. TheAnglo-Australian Planet Search team initially did not detect the planet in 2004,[6] though a solution was made by 2006.[7] TheCORALIE data was finally published in 2013.[3]
TheIRASinfrared spacetelescope detected anexcess of infrared radiation from the star, indicating a possiblecircumstellar disk.[8] Out of the 300 nearest Sun-like stars, the disk has the highest fractionalluminosity out of all of them.[9] It is unusually bright, but not unusually massive; the lower bound of the mass is 8 times that of the Earth.[9]
The inclination of the disk is relatively high,[10] and the disk is asymmetrical, being more extended in the northeast direction than the southwest.[9] It extends from 34astronomical units (AU) at the inner edge to 134 AU at the outer edge. The inner edge is sharp, suggesting the existence of a planet that carved out the edge. HD 10647 b, with a semimajor axis of about 2 AU, is too far to be responsible. However, other potential planets may be responsible for this feature.[9]
There is some evidence for an additional, warmasteroid belt-like component further in, at 3 to 10 AU away from the star.[9]
| Companion (in order from star) | Mass | Semimajor axis (AU) | Orbital period (days) | Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b[3] | >0.94 ± 0.08 MJ | 2.015 ± 0.011 | 989.2 ± 8.1 | 0.15 ± 0.08 | — | — |
| Dust disk[9] | 3–10AU | — | — | |||
| Dust disk[9] | 34–134AU | 76.1 ± 1.0° | — | |||
