GJ 1151
 Artist's impression of GJ 1151 and GJ 1151 b. | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Ursa Major |
| Right ascension | 11h 50m 57.72145s[1] |
| Declination | +48° 22′ 38.5625″[1] |
| Apparent magnitude (V) | 14.008[2] |
| Characteristics | |
| Spectral type | dM4.5[2] |
| B−V color index | 1.787[3] |
| Astrometry | |
| Radial velocity (Rv) | −36.01±0.28[4] km/s |
| Proper motion (μ) | RA: -1545.069[1] mas/yr Dec.: -962.724[1] mas/yr |
| Parallax (π) | 124.3378 ± 0.0549[1] mas |
| Distance | 26.23 ± 0.01 ly (8.043 ± 0.004 pc) |
| Absolute magnitude (MV) | 14.482±0.022[2] |
| Details | |
| Mass | 0.1540[3] M☉ |
| Radius | 0.1903[3] R☉ |
| Temperature | 3,143±26[2] K |
| Metallicity [Fe/H] | +0.04[2] dex |
| Rotational velocity (v sin i) | 2.0[4] km/s |
| Age | 2.5[3] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
GJ 1151 is a star located in the northern circumpolar constellation of Ursa Major at a distance of 26.2 light years from the Sun. It has a reddish hue and is too faint to be visible to the naked eye with an apparent visual magnitude of 14.0[2] The star is moving closer with a radial velocity of −36 km/s,[4] and has a relatively large proper motion, traversing the celestial sphere at a rate of 1.815″·yr−1.[6]
This is a small red dwarf star of spectral type dM4.5.[2] It is 2.5[3] billion years old and is spinning with a projected rotational velocity of 2.0 km/s.[4] The star has 15.4%[3] of the mass of the Sun and 19.0%[3] of the Sun's radius, with an effective temperature of 3,143 K.[2]
Planetary system?[]
In 2020, astronomers announced the discovery of radio emissions from the star which are consistent with the star having a magnetic interaction with a planet approximately the size of Earth, revolving in a 1-5 day long orbit.[7][8][9][10][11][12] Such an interaction would be analogous to a scaled-up version of the Jupiter-Io magnetic interaction, with GJ 1151 taking the role of Jupiter and its planet the role of Io. The discovery was confirmed in February 2021 utilizing a radial velocity method,[13] but refuted a month later as more data has become available.[14]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| (unconfirmed) | ≤1.2[14] M
|