20 Massalia

Source: Wikipedia, the free encyclopedia.

20 Massalia
SMASS = S[5]
8.3[12] to 12.0
6.50[5][11]
0.186" to 0.058"

Massalia (

minor planet designation: 20 Massalia) is a stony asteroid and the parent body of the Massalia family located in the inner region of the asteroid belt, approximately 145 kilometers (90 miles) in diameter. Discovered by Italian astronomer Annibale de Gasparis on 19 September 1852, it was named for the Latin name of the French city of Marseille, from which the independent discover Jean Chacornac sighted it the following night.[3] It was the first asteroid that was not assigned an iconic symbol by its discoverer.[13]

It came to

aphelion (farthest distance from the Sun) on 17 September 2023.[needs update
]

Classification and orbit

Massalia is the namesake and the

404), a very large inner belt asteroid family consisting of stony asteroids with very low inclinations.[6][15]: 23  It is by far the largest body in this family. The remaining family members are fragments ejected by a cratering event on Massalia.[16]

It orbits the Sun in the

semi-major axis of 2.41 AU). Its orbit has an eccentricity of 0.14 and an inclination of 1° with respect to the ecliptic.[5]

Physical characteristics

Massalia has an above-average density for S-type asteroids, similar to the density of

1 Ceres and 4 Vesta, most asteroids appear to have been significantly fractured, or are even rubble piles. In 1998, Bange estimated Massalia to have a mass of 5.2×1018 kg assuming that 4 Vesta has 1.35×10−10 solar mass.[10] The calculation of the mass of Massalia is dependent on the mass of 4 Vesta and perturbation of 44 Nysa.[10]

Light curve analysis indicates that Massalia's pole points towards ecliptic coordinates either (β, λ) = (45°, 10°) or (β, λ) = (45°, 190°) with a 10° uncertainty.[8] This gives an axial tilt of 45° in both cases. The shape reconstruction from light curves has been described as quite spherical with large planar, nonconvex parts of the surface.

In 1988 there was a search for satellites or dust orbiting this asteroid using the UH88 telescope at the Mauna Kea Observatories, but none were found.[17]

In February 2024, water molecules were discovered on 20 Massalia, alongside 7 Iris, marking the first time water molecules were detected on asteroids.[18][19]

Discovery

Massalia was discovered on 19 September 1852, by

Marseilles Observatory, France. It was Chacornac's discovery that was announced first. In the nineteenth century the variant spelling Massilia was often used. Asteroids discovered prior to Massalia were assigned iconic symbols, like the ones traditionally used to designate the planets. However, astronomers had begun to phase out this practice with the discovery of 16 Psyche in March 1852, and 20 Massalia (being the first object in the Solar System with a non-mythological name)[3]
was the first asteroid that was not assigned an iconic symbol.

References

  1. ^ a b "20 Massalia". Minor Planet Center. Retrieved 29 March 2018.
  2. ^ a b "Messalian, Massalian". Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription or participating institution membership required.)
  3. ^
    ISBN 978-3-540-00238-3
    .
  4. ^ John Craig (1869) The Universal English Dictionary
  5. ^ a b c d e f "JPL Small-Body Database Browser: 20 Massalia" (2018-01-24 last obs.). Jet Propulsion Laboratory. Retrieved 29 March 2018.
  6. ^ a b "Asteroid 20 Massalia". Small Bodies Data Ferret. Retrieved 24 October 2019.
  7. ^ a b c Jim Baer (2008). "Recent Asteroid Mass Determinations". Personal Website. Archived from the original on 2 July 2013. Retrieved 11 December 2008.
  8. ^
    doi:10.1006/icar.2002.6907
    .
  9. ^
    Bibcode:2004PDSS...12.....T
    . Retrieved 30 October 2019.
  10. ^
    Bibcode:1998A&A...340L...1B
    .
  11. ^ a b "LCDB Data for (20) Massalia". Asteroid Lightcurve Database (LCDB). Retrieved 29 March 2018.
  12. ISBN 978-0-395-34835-2
    .
  13. ^ Bala, Gavin Jared; Miller, Kirk (18 September 2023). "Unicode request for historical asteroid symbols" (PDF). unicode.org. Unicode. Retrieved 26 September 2023.
  14. ^ JPL Horizons (Opposition)
  15. ISBN 9780816532131
    .
  16. doi:10.1016/j.icarus.2005.12.010
    .
  17. Bibcode:1988LPI....19..405G
  18. doi:10.3847/PSJ/ad18b8
    .
  19. ^ Gamillo, Elizabeth (14 February 2024). "Water molecules identified on asteroids for the first time". Astronomy. Retrieved 27 March 2024.

External links

Retrieved from "https://en.wikipedia.org/w/index.php?title=20_Massalia&oldid=1220793705"