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Beta Pictoris c
Discovery
Discovered byLagrange et al. [1]
Discovery site La Silla Observatory
Discovery date19 August 2019 [1]
Radial velocity method
Orbital characteristics [2]
2.680+0.016
−0.015
  AU
Eccentricity0.314+0.024
−0.034
3.266+0.015
−0.012
  yr
Inclination88.947°+0.083°
−0.091°
31.081°+0.060°
−0.048°
243.890°+2.201°
−3.326°
Semi-amplitude137.999+16.442
−15.079
  m/s
Star Beta Pictoris
Physical characteristics
Mean radius
1.2±0.1  RJ [3]
Mass10.139+1.175
−1.031
  MJ
[2]
Temperature1250±50  K [3]

Beta Pictoris c (abbreviated as β Pic c) is the second exoplanet discovered orbiting the young star Beta Pictoris, located approximately 63 light-years away from Earth in the constellation of Pictor. Its mass is around nine times that of Jupiter, and it orbits at around 2.7 astronomical units (AU) from Beta Pictoris, about 3.5 times closer to its parent star than Beta Pictoris b. [1] It has an orbital period of 1,200 days (3.3 years). [1] The orbit of Beta Pictoris c is moderately eccentric, with an eccentricity of 0.24. [4] [5]

This exoplanet is notable for having been detected by three different methods: initially radial velocity, [1] then direct imaging [3] and astrometry. [6]

Physical characteristics

Mass and radius

Beta Pictoris c is a super-Jupiter, an exoplanet that has a radius and mass greater than that of the planet Jupiter. It has a mass of around 10 Jupiter masses (MJ) [1] and a radius of about 1.2 times that of Jupiter. [3]

Host star

The planet orbits an A-type main sequence star named Beta Pictoris. The star has a mass of 1.75 solar masses (M) and a radius of 1.8 solar radii (R). It has a surface temperature of 8056 K and is only 12 million years old. [7] It is slightly metal-rich, with a metallicity ( Fe/ H) of 0.06, or 112% of that found in the Sun. [8] Its luminosity ( L) is 8.7 times that of the Sun.

Orbit

Beta Pictoris c orbits at around 2.7 astronomical units (400 million kilometres) from Beta Pictoris, about 3.5 times closer than Beta Pictoris b. [5] It has an orbital period of 1,200 days (3.3 years). [1] The planet spends most or all of its orbit in the habitable zone. [9]

Discovery

Beta Pictoris c was detected indirectly, through 10 years of observation [10] of radial velocity data from the High Accuracy Radial Velocity Planet Searcher (HARPS) spectroscope on the European Southern Observatory's ESO 3.6 m Telescope at La Silla Observatory in Chile by a worldwide team led by Anne-Marie Lagrange, as the discovery of the planet was publicly announced in August 2019. [1] This discovery was described as being able to help scientists further understand the formation of planetary systems and their evolution in the early stages. [4] In October 2020, new images of the exoplanet were revealed. [11]

The European Southern Observatory confirmed the presence of Beta Pictoris c, on 6 October 2020, through the use of optical interferometry. [3] With a semi-major axis of approximatively 2.7 astronomical units, Beta Pictoris c is, as of 2020, the closest extrasolar planet to its star ever photographed. [4]

As of 2022, the orbital parameters and mass of Beta Pictoris c have been measured using a combination of data from radial velocity, astrometry, and imaging, [12] showing that it is about 10.1 times the mass of Jupiter, on an eccentric orbit (eccentricity 0.31) with a semi-major axis of about 2.7 AU and an orbital period of about 3.3 years. [2]

References

  1. ^ a b c d e f g h Lagrange, A.-M.; Meunier, Pascal Rubini; Keppler, Miriam; Galland, Franck; et al. (19 August 2019). "Evidence for an additional planet in the β Pictoris system". Nature Astronomy. 3 (12): 1135–1142. Bibcode: 2019NatAs...3.1135L. doi: 10.1038/s41550-019-0857-1. S2CID  202126059. Retrieved 20 August 2019.
  2. ^ a b c Feng, Fabo; Butler, R. Paul; et al. (August 2022). "3D Selection of 167 Substellar Companions to Nearby Stars". The Astrophysical Journal Supplement Series. 262 (21): 21. arXiv: 2208.12720. Bibcode: 2022ApJS..262...21F. doi: 10.3847/1538-4365/ac7e57. S2CID  251864022.
  3. ^ a b c d e Nowak, M.; et al. (6 October 2020). "Direct confirmation of the radial-velocity planet β Pictoris c". Astronomy & Astrophysics. 642: L2. arXiv: 2010.04442. Bibcode: 2020A&A...642L...2N. doi: 10.1051/0004-6361/202039039. Retrieved 26 August 2020.
  4. ^ a b c Lagrange, Anne-Marie (October 2020). Forveille, Thierry (ed.). "Unveiling the β Pictoris system, coupling high contrast imaging, interferometric, and radial velocity data". Astronomy & Astrophysics. 642. EDP Sciences: A18. Bibcode: 2020A&A...642A..18L. doi: 10.1051/0004-6361/202038823. hdl: 20.500.11850/447629. ISSN  0004-6361. Retrieved 7 October 2020.
  5. ^ a b Young, Monica (19 August 2019). "Beta Pic's New Planet, Jupiter's Fuzzy Core & An Ancient Star". Sky & Telescope. Retrieved 19 August 2019.
  6. ^ Brandt, G. Mirek; Brandt, Timothy D.; Dupuy, Trent J.; Li, Yiting; Michalik, Daniel (2021). "Precise Dynamical Masses and Orbital Fits for β Pic b and β Pic C". The Astronomical Journal. 161 (4): 179. arXiv: 2011.06215. Bibcode: 2021AJ....161..179B. doi: 10.3847/1538-3881/abdc2e. S2CID  226306610.
  7. ^ Webb, R. A.; Bessell, M. S.; Song, Inseok; Zuckerman, B. (30 October 2001). "The β Pictoris Moving Group". The Astrophysical Journal Letters. 562 (1): L87–L90. Bibcode: 2001ApJ...562L..87Z. doi: 10.1086/337968. S2CID  120493760.
  8. ^ Gray, R. O.; et al. (2006). "Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 pc—The Southern Sample". The Astronomical Journal. 132 (1): 161–170. arXiv: astro-ph/0603770. Bibcode: 2006AJ....132..161G. doi: 10.1086/504637. S2CID  250741593.
  9. ^ "What is the habitable zone around my star?". Worldbuilding Stack Exchange. Retrieved 30 November 2023.
  10. ^ "A second planet in the Beta Pictoris system". Nanowerk. 19 August 2019. Retrieved 20 August 2019.
  11. ^ Starr, Michelle (2 October 2020). "Scientists Reveal First Direct Image of an Exoplanet Only 63 Light-Years Away". sciencealert.com. Retrieved 2 October 2020.
  12. ^ Lacour, S.; et al. (2021). "The mass of β Pictoris c from β Pictoris b orbital motion". Astronomy & Astrophysics. 654: L2. arXiv: 2109.10671. Bibcode: 2021A&A...654L...2L. doi: 10.1051/0004-6361/202141889. S2CID  237592885.