Gliese 229 B

binary brown dwarf in the Lupus constellation

Thing brown_dwarf Q1152575

Facts

24 properties

Instance of: brown dwarf, astronomical radio source^[2]
Part of: Gliese 229^[5]
Apparent magnitude: 14.4 (14–14.4, n=3)^[13]^[14]^[15]
Argument of periapsis: 358.285
Catalog code: GJ 229 B, HD 42581B, WDS J06106-2152B^[7]^[8]^[9]
Constellation: Lepus^[3]
Declination: -21.866667
Declination component of proper motion: -714.1
Discovery method: direct imaging^[11]
Distance from Earth: 5.8
Epoch: J2000.0
M sin i: 1.61971^[17]
Mass: 60.423^[18]
Orbital eccentricity: 0.853^[12]
Orbital inclination: 5.497^[16]
Orbital period: 79231.9^[20]
Parallax: 173.19^[21]
Parent astronomical body: Gliese 229 A^[6]
Radius: 1.105^[19]
Right ascension: 92.645
Right ascension component of proper motion: -137.0
Semi-major axis of an orbit: 28.933^[22]
Spectral class: T6.5^[4]
Time of discovery or invention: 1995^[10]

🏷️ Also known as

en HD 42581 B en HD 42581B en GJ 229 B en GJ 229B en Gliese 229 B en Gliese 229B ar جليزا 229B ar جليزا ٢٢٩B nl Gliese 229 nl HD 42581b uk Глізе 229 B

🔖 Identifiers · 6

Image (Wikimedia Commons): Brown Dwarf Gliese 229B.jpg ↗
ARICNS: 00490
Encyclopædia Britannica Online ID: topic/Gliese-229-B
Extrasolar Planets Encyclopaedia exoplanet ID: gj_229_ba--6536
Google Knowledge Graph ID: /g/120x5z_b
SIMBAD ID: HD 42581B

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🔗 Connections

Instance of 2

brown dwarf, astronomical radio source

Belongs to 1

Gliese 229

Constellation 1

Lepus

Epoch 1

J2000.0

Part of 1

Gliese 229

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Summary

Gliese 229 B is a brown dwarf^[1].

⭐ Popularity Graph

6/100 established

🌐 Wiki Languages

8 / 428 langs

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🌐 Available in 8 languages

enGliese 229 B arجليزا 229B itGliese 229 B nlGliese 229B noGliese 229 b plGliese 229B svGliese 229 b ukГлізе 229 B

References

Programmatic citations — every numbered marker resolves to a verifiable graph row below.

Direct Wikidata claims

[2] ↑ Gliese 229 B — instance of (P31): astronomical radio source. SIMBAD. wikidata.org.
[3] ↑ Gliese 229 B — constellation (P59): Lepus. wikidata.org.
[4] ↑ Gliese 229 B — spectral class (P215): T6.5. The Spectra of T Dwarfs. I. Near‐Infrared Data and Spectral Classification. wikidata.org.
[5] ↑ Gliese 229 B — part of (P361): Gliese 229. wikidata.org.
[6] ↑ Gliese 229 B — parent astronomical body (P397): Gliese 229 A. Extrasolar Planets Encyclopaedia. wikidata.org.
[7] ↑ Gliese 229 B — catalog code (P528): GJ 229 B. SIMBAD. wikidata.org.
[8] ↑ Gliese 229 B — catalog code (P528): HD 42581B. SIMBAD. wikidata.org.
[9] ↑ Gliese 229 B — catalog code (P528): WDS J06106-2152B. SIMBAD. wikidata.org.
[10] ↑ Gliese 229 B — time of discovery or invention (P575): 1995. Extrasolar Planets Encyclopaedia. wikidata.org.
[11] ↑ Gliese 229 B — discovery method (P1046): direct imaging. Extrasolar Planets Encyclopaedia. wikidata.org.
[12] ↑ Gliese 229 B — orbital eccentricity (P1096): {'amount': '+0.853'}. 3-D selection of 167 sub-stellar companions to nearby stars. wikidata.org.
[13] ↑ Gliese 229 B — apparent magnitude (P1215): {'amount': '+14.01'}. The Brown Dwarf Kinematics Project (BDKP). III. Parallaxes for 70 ultracool dwarfs. wikidata.org.
[14] ↑ Gliese 229 B — apparent magnitude (P1215): {'amount': '+14.36'}. The Brown Dwarf Kinematics Project (BDKP). III. Parallaxes for 70 ultracool dwarfs. wikidata.org.
[15] ↑ Gliese 229 B — apparent magnitude (P1215): {'amount': '+14.36'}. The Brown Dwarf Kinematics Project (BDKP). III. Parallaxes for 70 ultracool dwarfs. wikidata.org.
[16] ↑ Gliese 229 B — orbital inclination (P2045): 5.497 degree. 3-D selection of 167 sub-stellar companions to nearby stars. wikidata.org.
[17] ↑ Gliese 229 B — M sin i (P2051): 1.61971 Jupiter mass. Search for Nearby Earth Analogs. II. Detection of Five New Planets, Eight Planet Candidates, and Confirmation of Three Planets around Nine Nearby M Dwarfs. wikidata.org.
[18] ↑ Gliese 229 B — mass (P2067): 60.423 Jupiter mass. 3-D selection of 167 sub-stellar companions to nearby stars. wikidata.org.
[19] ↑ Gliese 229 B — radius (P2120): 1.105 Jupiter radius. Extrasolar Planets Encyclopaedia. wikidata.org.
[20] ↑ Gliese 229 B — orbital period (P2146): 79231.9 day. 3-D selection of 167 sub-stellar companions to nearby stars. wikidata.org.
[21] ↑ Gliese 229 B — parallax (P2214): 173.19 milliarcsecond. The Brown Dwarf Kinematics Project (BDKP). III. Parallaxes for 70 ultracool dwarfs. wikidata.org.
[22] ↑ Gliese 229 B — semi-major axis of an orbit (P2233): 28.933 astronomical unit. 3-D selection of 167 sub-stellar companions to nearby stars. wikidata.org.

Class ancestry

[1] ↑ Gliese 229 B is an instance of brown dwarf (Q101600) [P31, primary]. Wikidata. wikidata.org.

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APA 4ort.xyz Knowledge Graph. (2026). Gliese 229 B. Retrieved November 4, 2026, from https://4ort.xyz/entity/gliese-229-b

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BibTeX

@misc{4ortxyz_gliese-229-b_2026, author = {{4ort.xyz Knowledge Graph}}, title = {{Gliese 229 B}}, year = {2026}, url = {https://4ort.xyz/entity/gliese-229-b}, note = {Accessed: 2026-11-04}}

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