29 Amphitrite

Discovery

Amphitrite was discovered by Albert Marth on 1 March 1854, at the private South Villa Observatory, in Regent's Park, London. It was Marth's only asteroid discovery. Its name was chosen by George Bishop, the owner of the observatory, who named it after Amphitrite, a sea goddess in Greek mythology. Its historical symbol was a shell and star; it was encoded in Unicode 17.0 as U+1CECF 𜻏 ([[File:Amphitrite symbol (fixed width).svg|12px]]).{{cite web | access-date = September 9, 2025 | url-status = live

Characteristics

Amphitrite's orbit is less eccentric and inclined than those of its larger cousins; indeed, it is the most circular of any asteroid discovered up to that point. As a consequence, it never becomes as bright as Iris or Hebe, especially as it is much further from the Sun than those asteroids. It can reach magnitudes of around +8.6 at a favorable opposition, but usually is around the binocular limit of +9.5.

In 2007, James Baer and Steven R. Chesley estimated Amphitrite to have a mass of 1.9 kg. A 2008 estimate by Baer suggests it has a mass of 1.18 kg.

A satellite of the asteroid is suspected to exist, based on lightcurve data collected by Edward F. Tedesco. In 1988 a search for satellites or dust orbiting this asteroid was performed using the UH88 telescope at the Mauna Kea Observatories, but neither were found.

Proposed exploration

In 1984, while determining the Galileo mission's prelaunch trajectory to Jupiter, JPL engineers found out that if the spacecraft launched on May 1986, it could perform a flyby of 29 Amphitrite at a distance of 6200 mi on 6 December 1986. However, with the Challenger disaster delaying the launch to October 1989, the flyby was ultimately cancelled.

Notes

References

References

1. Noah Webster (1884) ''A Practical Dictionary of the English Language''
2. P. Vernazza et al. (2021) VLT/SPHERE imaging survey of the largest main-belt asteroids: Final results and synthesis. ''Astronomy & Astrophysics'' 54, A56
3. (18 September 2023). "Unicode request for historical asteroid symbols". Unicode.
4. Baer, James. (2008). "Astrometric masses of 21 asteroids, and an integrated asteroid ephemeris". Celestial Mechanics and Dynamical Astronomy.
5. Tedesco, E. F.. (March 1979). "Binary Asteroids: Evidence for Their Existence from Lightcurves". Science.
6. van Flandern, T. C.. (1979). "Satellites of asteroids". [[University of Arizona Press]].
7. "JPL Small-Body Database Browser: 29 Amphitrite". [[Jet Propulsion Laboratory]].
8. Schmadel, Lutz D.. (2007). "Dictionary of Minor Planet Names – (29) Amphitrite". Springer Berlin Heidelberg.
9. "29 Amphitrite". Minor Planet Center.
10. (August 2014). "Main-belt Asteroids with WISE/NEOWISE: Near-infrared Albedos". The Astrophysical Journal.
11. "LCDB Data for (29) Amphitrite". Asteroid Lightcurve Database (LCDB).
12. "Asteroid 29 Amphitrite". Small Bodies Data Ferret.
13. "Asteroid (29) Amphitrite". AstDyS-2, Asteroids – Dynamic Site.
14. (November 2011). "NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results". The Astrophysical Journal.
15. (October 2004). "IRAS Minor Planet Survey V6.0". NASA Planetary Data System.
16. (October 2011). "Asteroid Catalog Using Akari: AKARI/IRC Mid-Infrared Asteroid Survey". Publications of the Astronomical Society of Japan.
17. (September 2013). "Sizes of main-belt asteroids by combining shape models and Keck adaptive optics observations". Icarus.
18. (March 1988). "A Search for Satellites and Dust Belts Around Asteroids: Negative Results". Abstracts of the Lunar and Planetary Science Conference.