GJ 3634

Last updated

GJ 3634
Observation data
Epoch J2000       Equinox J2000
Constellation Hydra
Right ascension 10h 58m 35.08837s [1]
Declination −31° 08 38.2008 [1]
Apparent magnitude  (V)11.95 [2]
Characteristics
Evolutionary stage Main sequence
Spectral type M2.5V [2]
Astrometry
Radial velocity (Rv)4.93±0.26 [1]  km/s
Proper motion (μ)RA: -566.980  mas/yr [1]
Dec.: -91.397  mas/yr [1]
Parallax (π)49.0331 ± 0.0241  mas [1]
Distance 66.52 ± 0.03  ly
(20.39 ± 0.01  pc)
Details
Mass 0.45 (± 0.05) [2]   M
Radius 0.43 (±0.03) [2]   R
Luminosity 0.02 [3]   L
Metallicity [Fe/H]+0.04±0.06 [4]   dex
Age > 3 [3]   Gyr
Other designations
LP 905-36
LHS 2335
2MASS J10583513-3108382
Database references
SIMBAD data
Exoplanet Archive data
ARICNS data

GJ 3634 (sometimes Gliese 3634) is a red dwarf star in the Hydra constellation. One planet has been discovered in its orbit, GJ 3634 b. GJ 3634 is under half the mass and size of the Sun, and is estimated to be at least a billion years younger, and lies near to Earth, with a distance of 66.5 light-years (20.4 parsecs ). [1] It was targeted by astronomers during an over six-year survey of red dwarfs. The astronomers had recently changed their strategy to search for planets with extremely short orbits so they could narrow down candidates that transited, or crossed in front of, their host stars as seen from the Earth. The super-Earth GJ 3634 b was the first planet discovered using this new strategy. [3] The planet was confirmed using Doppler spectroscopy, or the observation and extrapolation of data from a recorded Doppler effect in the star's light, but later observations found no transiting pattern. [3] The planet was published by its discoverers on February 8, 2011.

Contents

Naming and discovery

GJ 3634 is named for its location in the Gliese Catalogue of Nearby Stars; a later expansion of the original catalogue was compiled jointly by Gliese and Hartmut Jahreiß. The Third Catalogue, the most recent catalogue, was formed to tag all then-known stars within 25 parsecs of Earth (81.54 light years). [5] GJ 3634 was first catalogued in 1987. [3] The discoverers of GJ 3634 b worked through the High Accuracy Radial Velocity Planet Searcher (HARPS) at the European Southern Observatory's La Silla Observatory in Chile for over six years in search of planets that orbited low-mass red dwarfs. After the discoveries of eleven prior planets, the researchers changed their strategy to search for planets with extremely short orbits. They would first discover the system using the radial velocity method, in which an observed Doppler shift in the star's light would be measured and interpreted; and would then follow up with a search for transits, in which the planet crosses in front of and dims its star as seen from Earth. Radial velocity measurements would help determine the most efficient and time-effective means of observing potential planetary transits. [3]

Radial velocity measurements revealed the existence of a planet with a mass of at least 7 Earths. This planet, GJ 3634 b, became the first planet to be discovered under the new strategy. [3] The team of astronomers then followed up with transit measurements using instruments on the Spitzer Space Telescope; they found that there was most likely no transit event present at the star, but they were able to discover its true mass. [3] GJ 3634 b was published to the journal Astronomy and Astrophysics on February 8, 2011. [3]

Characteristics

GJ 3634 is an M-type red dwarf, a cool, small and dim star that shines with reddish light. It lies in the Hydra constellation. The star is 45% the mass of the Sun, and is 43% the Sun's size. GJ 3634, described by its discoverers as an "intermediately active star," has a luminosity of 0.02, meaning that it releases about 2% of the energy that the Sun radiates. The star is relatively metal-poor; with a metallicity of [Fe/H] -0.10, GJ 3634 has 79% the amount of iron that has been measured in the Sun. With an estimated age of more than three billion years, the star is similar in age to that of the Sun. [3]

GJ 3634 has an apparent magnitude of 11.95. Thus, despite its relative proximity at 66.5 light-years (20.4 parsecs ) away from the Earth, it cannot be seen with the unaided eye. [2] The star is of a similar distance from Earth as planet-bearing 51 Pegasi, which lies at a distance of 50.6 light-years (15.5 parsecs). [6]

Planetary system

The GJ 3634 planetary system [2]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b 8.4 +4.0
1.5
  M🜨
0.02872.645610.0859+18
24
°
(unconfirmed)>32 M🜨 >0.6>200

GJ 3634 has one confirmed planet in orbit: GJ 3634 b. The planet was called a super-Earth by its discoverers because of its mass, which was deduced to be 8.4 times that of Earth's [3] and 0.02 times that of Jupiter's. [2] GJ 3634 b has an extremely short orbital period, orbiting GJ 3634 every 2.64561 days. The planet orbits near to its star, and is at an average distance of 0.0287 AU away. It has an orbital eccentricity of 0.08, meaning that its orbit is very circular. [2]

The initial study into the system suggests that a second planet in the inner system is unlikely. The discoverers of GJ 3634 b, however, noted the possible signal of a secondary body of an unknown nature that most likely orbits GJ 3634 with a period longer than 200 days and a mass that is at least double that of Neptune. [3]

Related Research Articles

<span class="mw-page-title-main">Gliese 876</span> Star in the constellation Aquarius

Gliese 876 is a red dwarf star 15.2 light-years away from Earth in the constellation of Aquarius. It is one of the closest known stars to the Sun confirmed to possess a planetary system with more than two planets, after GJ 1061, YZ Ceti, Tau Ceti, and Wolf 1061; as of 2018, four extrasolar planets have been found to orbit the star. The planetary system is also notable for the orbital properties of its planets. It is the only known system of orbital companions to exhibit a near-triple conjunction in the rare phenomenon of Laplace resonance. It is also the first extrasolar system around a normal star with measured coplanarity. While planets b and c are located in the system's habitable zone, they are giant planets believed to be analogous to Jupiter.

<span class="mw-page-title-main">Gliese 436</span> Star in the constellation Leo

Gliese 436 is a red dwarf located 31.9 light-years away in the zodiac constellation of Leo. It has an apparent visual magnitude of 10.67, which is much too faint to be seen with the naked eye. However, it can be viewed with even a modest telescope of 2.4 in (6 cm) aperture. In 2004, the existence of an extrasolar planet, Gliese 436 b, was verified as orbiting the star. This planet was later discovered to transit its host star.

Gliese 581 is a red dwarf star of spectral type M3V which hosts a planetary system, 20.5 light-years away from Earth in the Libra constellation. Its estimated mass is about a third of that of the Sun, and it is the 101st closest known star system to the Sun. Gliese 581 is one of the oldest, least active M dwarfs known. Its low stellar activity improves the likelihood of its planets retaining significant atmospheres, and lessens the sterilizing impact of stellar flares.

<span class="mw-page-title-main">Gliese 581b</span> Gas giant orbiting Gliese 581

Gliese 581b or Gl 581b is an exoplanet orbiting within the Gliese 581 system, located 20.5 light-years away from Earth in the Libra constellation. It is the first planet discovered of three confirmed in the system so far, and the second in order from the star.

<span class="mw-page-title-main">Gliese 876 d</span> Super-Earth orbiting Gliese 876

Gliese 876 d is an exoplanet 15.2 light-years away in the constellation of Aquarius. The planet was the third planet discovered orbiting the red dwarf Gliese 876, and is the innermost planet in the system. It was the lowest-mass known exoplanet apart from the pulsar planets orbiting PSR B1257+12 at the time of its discovery. Due to its low mass, it can be categorized as a super-Earth.

<span class="mw-page-title-main">Gliese 581d</span> Contested super-Earth orbiting Gliese 581

Gliese 581d is a doubtful, and frequently disputed, exoplanet candidate orbiting within the Gliese 581 system, approximately 20.4 light-years away in the Libra constellation. It was the third planet claimed in the system and the fourth or fifth in order from the star. Multiple subsequent studies found that the planetary signal in fact originates from stellar activity, and thus the planet does not exist, but this remains disputed.

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.

<span class="mw-page-title-main">Gliese 581e</span> Terrestrial planet orbiting Gliese 581

Gliese 581e or Gl 581e is an exoplanet orbiting within the Gliese 581 system, located 20.5 light-years away from Earth in the Libra constellation. It is the third planet discovered in the system and the first in order from the star.

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.

GJ 3634 b is a super-Earth exoplanet in the orbit of the nearby red dwarf GJ 3634 at approximately 64.5 light-years in constellation Hydra. The planet is approximately eight times the mass of Earth, and orbits its star every two and a half days at a distance of 0.0287 AU. The planet was the first to be discovered by a group of astronomers searching for exoplanets in the orbit of very-low-mass stars after the team reorganized their strategy, choosing to search for targets that they could also confirm using the transit method. However, a transit event associated with GJ 3634 b was not detected. The planet's discovery was published in Astronomy and Astrophysics on February 8, 2011.

Gliese 754 is a dim star in the southern constellation of Telescopium. It has an apparent visual magnitude of 12.25, which requires a telescope to view. The star is located at a distance of 19.3 light-years from the Sun based on parallax, and it is drifting further away with a radial velocity of +6 km/s. It is one of the hundred closest stars to the Solar System. Calculations of its orbit around the Milky Way showed that it is eccentric, and indicate that it might be a thick disk object.

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.

Luyten b is a confirmed exoplanet, likely rocky, orbiting within the habitable zone of the nearby red dwarf Luyten's Star. It is the fourth-closest potentially habitable exoplanet known, at a distance of 12 light-years. Only Proxima Centauri b, Ross 128 b, and GJ 1061 d are closer. Discovered alongside Gliese 273c in June 2017, Luyten b is a super-Earth of around 2.89 times the mass of Earth and receives only 6% more starlight than Earth, making it one of the best candidates for habitability.

GJ 3470, proper name Kaewkosin, is a red dwarf star located in the constellation of Cancer, 96 light-years away from Earth. With a faint apparent magnitude of 12.3, it is not visible to the naked eye. It hosts one known exoplanet, GJ 3470 b.

<span class="mw-page-title-main">Gliese 15 Ac</span> Subjovian planet orbiting Gliese 15 A

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.

<span class="mw-page-title-main">GJ 1002</span> Red dwarf star in the constellation Cetus

GJ 1002 is a nearby red dwarf star, located 15.8 light-years away from the Solar System in the constellation of Cetus. The star has 12% the mass and 14% the radius of the Sun, and a temperature of 3,024 K. It hosts a system of two known exoplanets.

<span class="mw-page-title-main">Wolf 1069</span> Red dwarf star in the constellation Cygnus

Wolf 1069 is a red dwarf star located 31.2 light-years away from the Solar System in the constellation of Cygnus. The star has 17% the mass and 18% the radius of the Sun, a temperature of 3,158 K, and a slow rotation period of 150–170 days. It hosts one known exoplanet called Wolf 1069 b which could possibly sustain life.

<span class="mw-page-title-main">GJ 3929</span> Red dwarf star in the constellation Corona Borealis

GJ 3929, also known as Gliese 3929 and TOI-2013, is a red dwarf star located 51.6 light-years from Earth, in the constellation Corona Borealis. With an apparent magnitude of 12, it is not visible to the naked eye. In 2022, two exoplanets were detected orbiting the star.

<span class="mw-page-title-main">Gliese 12</span> Red dwarf star

Gliese 12 is a red dwarf star located 39.7 light-years away in the constellation Pisces. It has about 24% the mass and 26% the radius of the Sun, and a temperature of about 3,296 K. It is an inactive star and hosts one known exoplanet.

References

  1. 1 2 3 4 5 6 7 Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv: 2208.00211 . Bibcode:2023A&A...674A...1G. doi: 10.1051/0004-6361/202243940 . S2CID   244398875. Gaia DR3 record for this source at VizieR.
  2. 1 2 3 4 5 6 7 8 Jean Schneider (2011). "Notes for star GJ 3634". Extrasolar Planets Encyclopaedia . Archived from the original on May 5, 2011. Retrieved 8 April 2011.
  3. 1 2 3 4 5 6 7 8 9 10 11 12 Bonfils, Xavier; Gillon, Michael (2011). "A short-period super-Earth orbiting the M2.5 dwarf GJ 3634: Detection with Harps velocimetry and transit search with Spitzer photometry". Astronomy and Astrophysics . 528. European Southern Observatory. arXiv: 1102.1420 . Bibcode:2011yCat..35280111B. doi: 10.1051/0004-6361/201015981 . S2CID   204933219.
  4. Lindgren, Sara; Heiter, Ulrike (2017). "Metallicity determination of M dwarfs. Expanded parameter range in metallicity and effective temperature". Astronomy and Astrophysics. 604: A97. arXiv: 1705.08785 . Bibcode:2017A&A...604A..97L. doi:10.1051/0004-6361/201730715. S2CID   119216828.
  5. Browse Software Development Team (12 May 2011). "CNS3 - Gliese Catalog of Nearby Stars, 3rd Edition". High Energy Astrophysics Science Archive Research Center at Goddard Space Flight Center . NASA . Retrieved 3 June 2011.
  6. Jean Schneider (2010). "Notes for Planet 51 Peg b". Extrasolar Planets Encyclopaedia . Retrieved 3 June 2011.