381 Myrrha

381 Myrrha
	381 Myrrha photographed in the constellation of Leo, with Messier 65, Messier 66 and NGC 3628 nearby
Discovery
Discovered by	Auguste Charlois
Discovery date	10 January 1894
Designations
Pronunciation	/ˈmɪrə, ˈmɜːrə/
Named after	Myrrha
Alternative designations	1894 AS
Minor planet category	Main belt
Orbital characteristics
	Epoch 31 July 2016 (JD 2457600.5)
	Uncertainty parameter 0
Observation arc	122.27 yr (44658 d)
Aphelion	3.5124 AU (525.45 Gm)
Perihelion	2.93357 AU (438.856 Gm)
Semi-major axis	3.22298 AU (482.151 Gm)
Eccentricity	0.089797
Orbital period (sidereal)	5.79 yr (2113.4 d)
Mean anomaly	350.739°
Mean motion	0° 10m 13.224s / day
Inclination	12.558°
Longitude of ascending node	125.102°
Argument of perihelion	142.930°
Physical characteristics
Dimensions	147.2×126.6 km
Mean diameter	123.41 ± 6.30 km (composite estimate); 131 ± 4 km; 127.639±1.686 km
Mass	(1.81±0.58)×1018 kg
Mean density	1.66 g/cm3
Synodic rotation period	6.571953+0.000003; −0.000004 h
Pole ecliptic longitude	237°+3°; −5°
Pole ecliptic latitude	82°+3°; −13°
Geometric albedo	0.064±0.004
Spectral type	C
Absolute magnitude (H)	8.38

381 Myrrha is a main-belt asteroid that was discovered by the French astronomer Auguste Charlois on January 10, 1894, in Nice. It has been classified as a C-type asteroid and is most likely composed of carbonaceous material.

Photometric observations of this asteroid at the Oakley Observatory in Terre Haute, Indiana during 2006 gave a light curve with a period of 6.572 ± 0.002 hours and a brightness variation of 0.34 ± 0.05 in magnitude.

10μ radiometric data collected from Kitt Peak in 1975 gave a diameter estimate of 126 km. An occultation of the star Alhena (γ Geminorum) by Myrrha was observed in Japan and China on January 13, 1991, allowing the size and shape of Myrrha to be properly clarified.

Notes

↑ Calculated from its standard gravitational parameter GM = 0.121±0.039 km³/s².
↑ Assuming a diameter of 128 km.

References

1 2 3 4 Yeomans, Donald K., "381 Myrrha", JPL Small-Body Database Browser, NASA Jet Propulsion Laboratory, retrieved 10 May 2016.
↑ Carry, B. (December 2012), "Density of asteroids", Planetary and Space Science, vol. 73, pp. 98–118, arXiv:1203.4336, Bibcode:2012P&SS...73...98C, doi:10.1016/j.pss.2012.03.009. See Table 1.
1 2 3 4 Podlewska-Gaca, E.; Marciniak, A.; Alí-Lagoa, V.; Bartczak, P.; Müller, T. G.; Szakáts, R.; Duffard, R.; Molnár, L.; Pál, A.; Butkiewicz-Bąk, M.; Dudziński, G.; Dziadura, K.; Antonini, P.; Asenjo, V.; Audejean, M.; et al. (June 2020). "Physical parameters of selected Gaia mass asteroids". Astronomy & Astrophysics. 638: A11. arXiv:2001.07030. Bibcode:2020A&A...638A..11P. doi:10.1051/0004-6361/201936380. ISSN 0004-6361. S2CID 210839599.
1 2 Fuentes-Muñoz, Oscar; Farnocchia, Davide; Giorgini, Jon D.; Park, Ryan S. (1 December 2025). "Asteroid Mass Estimation by Mutual Perturbations During Close Encounters After Gaia Focused Product Release". The Astronomical Journal. 170 (6): 353. Bibcode:2025AJ....170..353F. doi:10.3847/1538-3881/ae0cc9. ISSN 0004-6256. S2CID 283347135.
↑ "Numbered Minor Planets 1–5000", Discovery Circumstances, IAU Minor Planet center, retrieved 7 April 2013.
↑ Ditteon, Richard; Hawkins, Scot (September 2007), "Asteroid Lightcurve Analysis at the Oakley Observatory - October-November 2006", The Minor Planet Bulletin, vol. 34, no. 3, pp. 59–64, Bibcode:2007MPBu...34...59D.
↑ Morrison, D.; Chapman, C. R. (March 1976), "Radiometric diameters for an additional 22 asteroids", Astrophysical Journal, vol. 204, pp. 934–939, Bibcode:2008mgm..conf.2594S, doi:10.1142/9789812834300_0469, ISBN 978-981-283-426-3.
↑ Sato, I.; Soma, M.; Hirose, T. (April 1993). "The occultation of gamma Geminorum by the asteroid 381 Myrrha". The Astronomical Journal. 105: 1553. Bibcode:1993AJ....105.1553S. doi:10.1086/116535.

External links

381 Myrrha at AstDyS-2, Asteroids—Dynamic Site
- Ephemeris · Observation prediction · Orbital info · Proper elements · Observational info
381 Myrrha at the JPL Small-Body Database
- Close approach · Discovery · Ephemeris · Orbit viewer · Orbit parameters · Physical parameters

This article about a C-type asteroid native to the asteroid belt is a stub. You can help Wikipedia by adding missing information.

[5] Calculated from its standard gravitational parameter GM = 0.121±0.039 km³/s².

[6] Assuming a diameter of 128 km.

[JPL-1] 1 2 3 4 Yeomans, Donald K., "381 Myrrha", JPL Small-Body Database Browser, NASA Jet Propulsion Laboratory, retrieved 10 May 2016.

[Carry2012-2] Carry, B. (December 2012), "Density of asteroids", Planetary and Space Science, vol. 73, pp. 98–118, arXiv:1203.4336, Bibcode:2012P&SS...73...98C, doi:10.1016/j.pss.2012.03.009. See Table 1.

[Podlewska-Gaca2020-3] 1 2 3 4 Podlewska-Gaca, E.; Marciniak, A.; Alí-Lagoa, V.; Bartczak, P.; Müller, T. G.; Szakáts, R.; Duffard, R.; Molnár, L.; Pál, A.; Butkiewicz-Bąk, M.; Dudziński, G.; Dziadura, K.; Antonini, P.; Asenjo, V.; Audejean, M.; et al. (June 2020). "Physical parameters of selected Gaia mass asteroids". Astronomy & Astrophysics. 638: A11. arXiv:2001.07030. Bibcode:2020A&A...638A..11P. doi:10.1051/0004-6361/201936380. ISSN 0004-6361. S2CID 210839599.

[Fuentes-Muñoz2025-4] 1 2 Fuentes-Muñoz, Oscar; Farnocchia, Davide; Giorgini, Jon D.; Park, Ryan S. (1 December 2025). "Asteroid Mass Estimation by Mutual Perturbations During Close Encounters After Gaia Focused Product Release". The Astronomical Journal. 170 (6): 353. Bibcode:2025AJ....170..353F. doi:10.3847/1538-3881/ae0cc9. ISSN 0004-6256. S2CID 283347135.

[IAU_MPC-7] "Numbered Minor Planets 1–5000", Discovery Circumstances, IAU Minor Planet center, retrieved 7 April 2013.

[Warner2008-8] Ditteon, Richard; Hawkins, Scot (September 2007), "Asteroid Lightcurve Analysis at the Oakley Observatory - October-November 2006", The Minor Planet Bulletin, vol. 34, no. 3, pp. 59–64, Bibcode:2007MPBu...34...59D.

[Morrison1976-9] Morrison, D.; Chapman, C. R. (March 1976), "Radiometric diameters for an additional 22 asteroids", Astrophysical Journal, vol. 204, pp. 934–939, Bibcode:2008mgm..conf.2594S, doi:10.1142/9789812834300_0469, ISBN 978-981-283-426-3.

[Sato1993-10] Sato, I.; Soma, M.; Hirose, T. (April 1993). "The occultation of gamma Geminorum by the asteroid 381 Myrrha". The Astronomical Journal. 105: 1553. Bibcode:1993AJ....105.1553S. doi:10.1086/116535.