PROFILPELAJAR.COM

Beta Andromedae

Beta Andromedae
thumb
thumb

An image of Beta Andromedae (Mirach) next to a galaxy NGC 404 (Mirach's Ghost)
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Andromeda
Right ascension  01h 09m 43.91s
Declination +35° 37′ 13.8″
Apparent magnitude (V) 2.01 to 2.10
Characteristics
Evolutionary stage Red giant
Spectral type M0 III
Variable type Semiregular variable
Astrometry
Parallax (π)16.52 ± 0.56 mas
Distance197 ± 7 ly
(61 ± 2 pc)
Details
Mass2.49 M☉
Radius86.4 R☉
Luminosity1,675 L☉
Temperature3,762 ± 40 K
Age500 million-1 billion years
Other designations
Mirach, Beta Andromedae, Beta And, β And, 43 Andromedae, 43 And, HD 6860, HIP 5447, HR 337

Beta Andromedae (β And), also called Mirach, is a star in the constellation of Andromeda. It is the second-brightest star in the constellation and is easy to see without using a telescope. People often use it as a guide star to find the Andromeda Galaxy.[1] Its brightness changes slightly over time. It is a semiregular variable star, with an apparent magnitude that shifts between 2.01 and 2.10. It is located at around 197 light-years away from the Solar System.[2]

Mirach is a red giant star, with a radius 86.4 times that of the Sun. It was once a star like the Sun, but it depleted the hydrogen fuel in its core. Even though the star's surface is cooler than the Sun, it shines 1,675 times more brighter because of its size.[1]

In 2023, astronomers found out that this star has a substellar companion (likely a brown dwarf) orbiting it, using the radial velocity method. It orbits the star every 4.3 years.[3]

References

  1. ↑ 1.0 1.1 "bet and". simbad.cds.unistra.fr. Retrieved 2026-06-20.[permanent dead link]
  2. ↑ van Leeuwen, F. (November 2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357.
  3. ↑ Lee, Byeong-Cheol; Do, Hee-Jin (October 2023). "Long-period radial velocity variations of nine M red giants: The detection of sub-stellar companions around HD 6860 and HD 112300". Astronomy & Astrophysics. 678: A106. arXiv:2307.15897. Bibcode:2023A&A...678A.106L. doi:10.1051/0004-6361/202243725.


Content Disclaimer

Informasi ini disarikan dari Wikipedia dan disajikan kembali untuk tujuan edukasi. Konten tersedia di bawah lisensi CC BY-SA 3.0. Kami tidak bertanggung jawab atas ketidakakuratan data yang bersumber dari kontribusi publik tersebut.

  1. The information displayed on this website is sourced in part or in whole from Wikipedia and has been adapted for the purpose of restating it. We strive to provide accurate and relevant information, however:
  2. There is no guarantee of absolute accuracy. Wikipedia is an open, collaborative project that can be edited by anyone, so information is subject to change.
  3. It is not intended to constitute professional advice. The content displayed is for informational and educational purposes only. For important decisions (e.g., medical, legal, or financial), please consult a professional.
  4. Content copyright. Wikipedia is licensed under the Creative Commons Attribution-ShareAlike License (CC BY-SA). This means that content may be reused with appropriate attribution and shared under a similar license.
  5. Responsible use. Any risk arising from the use of information from this website is entirely the responsibility of the user.