Observation data Epoch J2000.0 Equinox J2000.0 | |
---|---|
Constellation | Ursa Major |
Right ascension | 11h 50m 57.72053s [1] |
Declination | +48° 22′ 38.5612″ [1] |
Apparent magnitude (V) | 14.008 [2] |
Characteristics | |
Spectral type | dM4.5 [2] |
B−V color index | 1.787 [3] |
Astrometry | |
Radial velocity (Rv) | −36.13±0.26 [1] km/s |
Proper motion (μ) | RA: -1545.069 mas/yr [1] Dec.: -962.724 mas/yr [1] |
Parallax (π) | 124.3378 ± 0.0549 mas [1] |
Distance | 26.23 ± 0.01 ly (8.043 ± 0.004 pc) |
Absolute magnitude (MV) | 14.482±0.022 [2] |
Details | |
Mass | 0.1639±0.0093 [4] M☉ |
Radius | 0.1781±0.0042 [4] R☉ |
Luminosity (bolometric) | 0.003315±0.000018 [4] L☉ |
Surface gravity (log g) | 5.09±0.09 [4] cgs |
Temperature | 3,143±26 [2] K |
Metallicity [Fe/H] | −0.12±0.10 [4] dex |
Rotation | 140±10 d |
Rotational velocity (v sin i) | 2.0 [5] 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 (8.0 parsecs ) 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, [5] and has a relatively large proper motion, traversing the celestial sphere at a rate of 1.815″ ·yr−1. [7]
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. [5] 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]
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. [8] [9] [10] [11] [12] [13] 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.
Two papers published only a month apart in 2021 discussed planet detection at GJ 1151 by the radial velocity method. One claimed the detection of a planet with a minimum mass of 2.5 M🜨 and a period of 2 days, supporting the radio emission detection, [14] while the other was unable to confirm this candidate planet, finding that the 2-day signal is likely caused by long-term variability, possibly connected to a more distant planet. [15] This second study placed an upper limit of 0.7-1.2 M🜨 on the minimum masses of any undetected planets with periods from 1-5 days. [15]
In 2023, a different planet was found, with a minimum mass of 10.6 M🜨 and a 390-day orbit, along with additional radial velocity variations. This new planet was referred to by the preprint version of the discovery paper as GJ 1151 b, but the published version of the paper, as well as the NASA Exoplanet Archive, refer to it as GJ 1151 c to differentiate it from the previous candidate. While the presence of a short-period planet associated with the radio emissions could not be completely ruled out, if such a planet exists its minimum mass must be less than 1.2 M🜨. [4]
Companion (in order from star) | Mass | Semimajor axis (AU) | Orbital period (days) | Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
c | ≥10.62+1.31 −1.47 M🜨 | 0.5714+0.0053 −0.0064 | 389.7+5.4 −6.5 | — | — | — |
Gliese 229 is a binary system composed of a red dwarf and the first brown dwarf seen by astronomers, 18.8 light years away in the constellation Lepus. The primary component has 58% of the mass of the Sun, 69% of the Sun's radius, and a very low projected rotation velocity of 1 km/s at the stellar equator.
Groombridge 34 is a binary star system in the northern constellation of Andromeda. It was listed as entry number 34 in A Catalogue of Circumpolar Stars, published posthumously in 1838 by British astronomer Stephen Groombridge. Based upon parallax measurements taken by the Gaia spacecraft, the system is located about 11.6 light-years from the Sun. This positions the pair among the nearest stars to the Solar System.
Gliese 674(GJ 674) is a small red dwarf star with an exoplanetary companion in the southern constellation of Ara. It is too faint to be visible to the naked eye, having an apparent visual magnitude of 9.38 and an absolute magnitude of 11.09. The system is located at a distance of 14.8 light-years from the Sun based on parallax measurements, but is drifting closer with a radial velocity of −2.9 km/s. It is a candidate member of the 200 million year old Castor stream of co-moving stars.
Gliese 849, or GJ 849, is a small, solitary star in the equatorial constellation of Aquarius. It has a reddish hue and is invisible to the naked eye with an apparent visual magnitude of 10.41. The distance to this star is 28.8 light-years based on parallax, but it is drifting closer to the Sun with a radial velocity of −15.3 km/s. It has a pair of confirmed gas giant companions.
Gliese 176 is a red dwarf in the constellation of Taurus. Based upon parallax measurements from the Hipparcos mission, it is located approximately 30 light-years away. The star is orbited by a Super-Earth.
HD 115404 is a binary star system located in the constellation Coma Berenices. Parallax measurements made by Hipparcos put the system at 36 light-years, or 11 parsecs, away. The combined apparent magnitude of the system is 6.52, with the magnitudes of the components being 6.66 and 9.50.
GJ 3379 is the nearest star in the Orion constellation, located at a distance of 17 light years from the Sun based on parallax. It is a single star with an apparent visual magnitude of +11.31 and an absolute magnitude of +12.71, therefore, the star is not visible with the naked eye. It is positioned in the upper left part of the Orion constellation, to the SSE of Betelgeuse. This star is drifting further away with a radial velocity of +30.0 kilometers per second. In the past, this star had a relatively close encounter with the Solar System. Some 161,000±6,000 years ago, it achieved a minimum distance of 4.08 ± 0.20 ly (1.25 ± 0.06 pc).
Gliese 806 is a star in the northern constellation of Cygnus, located about a degree to the southeast of the bright star Deneb. It is invisible to the naked eye with an apparent visual magnitude of +10.79. The star is located at a distance of 39.3 light years from the Sun based on stellar parallax. It is drifting closer with a radial velocity of −24.6 km/s, and is predicted to come to within 30.1 light-years in ~198,600 years. The star hosts two known planetary companions.
Gliese 179 is a small red dwarf star with an exoplanetary companion in the equatorial constellation of Orion. It is much too faint to be visible to the naked eye with an apparent visual magnitude of 11.94. The system is located at a distance of 40.5 light-years from the Sun based on parallax measurements, but is drifting closer with a radial velocity of –9 km/s. It is a high proper motion star, traversing the celestial sphere at an angular rate of 0.370″·yr−1.
Gliese 180, is a small red dwarf star in the equatorial constellation of Eridanus. It is invisible to the naked eye with an apparent visual magnitude of 10.9. The star is located at a distance of 39 light years from the Sun based on parallax, and is drifting closer with a radial velocity of −14.6 km/s. It has a high proper motion, traversing the sky at the rate of 0.765 arcseconds per year.
GJ 3323 is a nearby single star located in the equatorial constellation Eridanus, about 0.4° to the northwest of the naked eye star Psi Eridani. It is invisible to the naked eye with an apparent visual magnitude 12.20. Parallax measurements give a distance estimate of 17.5 light-years from the Sun. It is drifting further away with a radial velocity of +42.3 km/s. Roughly 104,000 years ago, the star is believed to have come to within 7.34 ± 0.16 light-years of the Solar System.
Gliese 251, also known as HIP 33226 or HD 265866, is a star located about 18 light years away from the Solar System. Located in the constellation of Gemini, it is the nearest star in this constellation. It is located near the boundary with Auriga, 49 arcminutes away from the bright star Theta Geminorum; due to its apparent magnitude of +9.89 it cannot be observed with the naked eye. The closest star to Gliese 251 is QY Aurigae, which is located 3.5 light years away.
GJ 625 is a small red dwarf star with an exoplanetary companion in the northern constellation of Draco. The system is located at a distance of 21.1 light-years from the Sun based on parallax, but is drifting closer with a radial velocity of −13 km/s. It is too faint to be visible to the naked eye, having an apparent visual magnitude of 10.13 and an absolute magnitude of 11.06.
Gliese 393, or GJ 393, is a single star in the equatorial constellation of Sextans, positioned about 1.5° to the NNW of Beta Sextantis. At an apparent visual magnitude of 9.65, it is much too faint to be seen with the unaided eye. This star is located at a distance of 22.9 light years from the Sun based on parallax, and is drifting further away with a radial velocity of +8.3 km/s. It has a large proper motion, traversing the celestial sphere at the rate of 0.950″ per year. The net velocity of this star relative to the Sun is 32.9 km/s. It shares a similar space motion as members of the AB Doradus moving group, but is considered a random interloper.
GJ 3512 is a nearby star in the northern circumpolar constellation of Ursa Major. It is invisible to the naked eye but can be observed using a telescope, having an apparent visual magnitude of +15.05. The star is located at a distance of 31 light-years from the Sun based on parallax. It has a high proper motion, traversing the celestial sphere at the rate of 1.311″ yr−1. The measurement of the star's radial velocity is poorly constrained, but it appears to be drifting further away at a rate of ~8 km/s.
Gliese 15 Ac is an exoplanet orbiting the nearby red dwarf star Gliese 15 A, which is part of a binary star system located about 11.6 light-years from the Sun. The planet was first proposed in October 2017 using radial velocity data from the CARMENES spectrograph, combined with measurements from the HARPS and HIRES spectrographs, and its existence was confirmed in April 2018 using HARPS-N data. It has a minimum mass 36 times that of Earth and orbits at around 5.4 astronomical units with a period of 7,600 days, an orbit which may have been sculpted by interaction with the companion star, Gliese 15 B. As of 2020, Gliese 15 Ac is the longest-period sub-Jovian planet discovered by radial velocity.