869 Mellena (prov. designation: A917 JB or 1917 BV) is a dark background asteroid from the central region of the asteroid belt. It was discovered on 9 May 1917, by astronomer Richard Schorr at the Bergedorf Observatory in Hamburg.[1] The carbonaceous C-type asteroid has a shorter than average rotation period of 6.5 hours and measures approximately 19 kilometers (12 miles) in diameter. It was named after Werner von Melle (1853–1937), mayor of Hamburg, who founded the discovering observatory.[2]

869 Mellena
Discovery [1]
Discovered byR. Schorr
Discovery siteBergedorf Obs.
Discovery date9 May 1917
Designations
(869) Mellena
Named after
Werner von Melle
(mayor of Hamburg)[2]
A917 JB · 1931 RC
1944 OB · 1952 DL2
1917 BV
main-belt[1][3] · (middle)
background[4][5]
Orbital characteristics[3]
Epoch 31 May 2020 (JD 2459000.5)
Uncertainty parameter 0
Observation arc102.66 yr (37,496 d)
Aphelion3.2807 AU
Perihelion2.0966 AU
2.6887 AU
Eccentricity0.2202
4.41 yr (1,610 d)
90.376°
0° 13m 24.96s / day
Inclination7.8385°
154.88°
107.09°
Physical characteristics
  • 18.45±0.32 km[6]
  • 18.52±0.8 km[7]
  • 21.193±0.090 km[8]
6.5155±0.0005 h[9]
  • 0.0565±0.005[7]
  • 0.057±0.022[8]
  • 0.058±0.002[6]
11.9[1][3]

Orbit and classification

edit

Mellena is a non-family asteroid of the main belt's background population when applying the hierarchical clustering method to its proper orbital elements.[4][5] It orbits the Sun in the central asteroid belt at a distance of 2.1–3.3 AU once every 4 years and 5 months (1,610 days; semi-major axis of 2.69 AU). Its orbit has an eccentricity of 0.22 and an inclination of 8° with respect to the ecliptic.[3]

Discovery

edit

Mellena was discovered by German astronomer Richard Schorr at the Bergedorf Observatory in Hamburg on 9 May 1917.[1] On the following night, it was independently discovered by Max Wolf at Heidelberg Observatory on 10 May 1917.[2] The Minor Planet Center, however, only credits the first discoverer. Schorr only discovered one more asteroid, 1240 Centenaria, and was honored with the naming of Mars-crosser 1235 Schorria, discovered by Wolf. Mellena's observation arc begins at Algiers Observatory in Northern Africa on 26 March 1930, almost 13 years after its official discovery observation at Bergedorf.[1]

Naming

edit

This minor planet was named after Werner von Melle (1853–1937), who was the mayor of Hamburg, Germany, in 1915 and during 1918–1919. He promoted the establishment of the University of Hamburg and founded the Bergedorf–Hamburg Observatory where this minor planet was discovered. The naming was also mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 85).[2]

Physical characteristics

edit

In both the Tholen- and SMASS-like taxonomy of the Small Solar System Objects Spectroscopic Survey (S3OS2) as well as in the SDSS-based taxonomy, Mellena is a common, carbonaceous C-type asteroid.[5][10][11]

Rotation period

edit

In May 2010, a rotational lightcurve of Mellena was obtained from photometric observations by Robert Stephens at the Santana (646) and GMARS (G79) observatories in California. Lightcurve analysis gave a well-defined rotation period of 6.5155±0.0005 hours with a brightness variation of 0.27±0.03 magnitude (U=3).[9] Subsequent observations were taken by Andrea Ferrero at the Bigmuskie Observatory (B88) in Mombercelli, Italy (U=2),[12] and Larry Owings at the Barnes Ridge Observatory in California in June 2010 (U=3),[13] as well as by Albino Carbognani Astronomical at the OAVdA Observatory (B04) in July 2010 (U=3−).[14] These observations gave a concurring period of (6.510±0.003), (6.510±0.001) and (6.515±0.001) hours with an amplitude of (0.25±0.02), (0.20±0.02) and (0.26±0.03) magnitude, respectively.[12]

Diameter and albedo

edit

According to the surveys carried out by the Japanese Akari satellite, the Infrared Astronomical Satellite IRAS, and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer (WISE), Mellena measures (18.45±0.32), (18.52±0.8) and (21.193±0.090) kilometers in diameter and its surface has an albedo of (0.058±0.002), (0.0565±0.005) and (0.057±0.022), respectively.[6][7][8] The Collaborative Asteroid Lightcurve Link derives an albedo of 0.0884 and a diameter of 18.64 kilometers based on an absolute magnitude of 11.9.[12] Alternative mean diameter measurements published by the WISE team include (15.23±3.47 km), (16.39±3.30 km), (17.77±0.46 km) and (21.953±0.153 km) with corresponding albedos of (0.12±0.17), (0.09±0.04), (0.065±0.009) and (0.0377±0.0020).[5][12]

References

edit
  1. ^ a b c d e f "869 Mellena (A917 JB)". Minor Planet Center. Retrieved 3 March 2020.
  2. ^ a b c d Schmadel, Lutz D. (2007). "(869) Mellena". Dictionary of Minor Planet Names. Springer Berlin Heidelberg. p. 79. doi:10.1007/978-3-540-29925-7_870. ISBN 978-3-540-00238-3.
  3. ^ a b c d "JPL Small-Body Database Browser: 869 Mellena (A917 JB)" (2020-01-06 last obs.). Jet Propulsion Laboratory. Retrieved 3 March 2020.
  4. ^ a b "Asteroid 869 Mellena – Proper Elements". AstDyS-2, Asteroids – Dynamic Site. Retrieved 3 March 2020.
  5. ^ a b c d "Asteroid 869 Mellena". Small Bodies Data Ferret. Retrieved 3 March 2020.
  6. ^ a b c Usui, Fumihiko; Kuroda, Daisuke; Müller, Thomas G.; Hasegawa, Sunao; Ishiguro, Masateru; Ootsubo, Takafumi; et al. (October 2011). "Asteroid Catalog Using Akari: AKARI/IRC Mid-Infrared Asteroid Survey". Publications of the Astronomical Society of Japan. 63 (5): 1117–1138. Bibcode:2011PASJ...63.1117U. doi:10.1093/pasj/63.5.1117. (online, AcuA catalog p. 153)
  7. ^ a b c Tedesco, E. F.; Noah, P. V.; Noah, M.; Price, S. D. (October 2004). "IRAS Minor Planet Survey V6.0". NASA Planetary Data System. 12: IRAS-A-FPA-3-RDR-IMPS-V6.0. Bibcode:2004PDSS...12.....T. Retrieved 3 March 2020.
  8. ^ a b c Masiero, Joseph R.; Grav, T.; Mainzer, A. K.; Nugent, C. R.; Bauer, J. M.; Stevenson, R.; et al. (August 2014). "Main-belt Asteroids with WISE/NEOWISE: Near-infrared Albedos". The Astrophysical Journal. 791 (2): 11. arXiv:1406.6645. Bibcode:2014ApJ...791..121M. doi:10.1088/0004-637X/791/2/121.
  9. ^ a b Stephens, Robert D. (October 2010). "Asteroids Observed from GMARS and Santana Observatories: 2010 April - June" (PDF). Minor Planet Bulletin. 37 (4): 159–161. Bibcode:2010MPBu...37..159S. ISSN 1052-8091.
  10. ^ a b Lazzaro, D.; Angeli, C. A.; Carvano, J. M.; Mothé-Diniz, T.; Duffard, R.; Florczak, M. (November 2004). "S3OS2: the visible spectroscopic survey of 820 asteroids" (PDF). Icarus. 172 (1): 179–220. Bibcode:2004Icar..172..179L. doi:10.1016/j.icarus.2004.06.006. Retrieved 3 March 2020.
  11. ^ a b Carvano, J. M.; Hasselmann, P. H.; Lazzaro, D.; Mothé-Diniz, T. (February 2010). "SDSS-based taxonomic classification and orbital distribution of main belt asteroids". Astronomy and Astrophysics. 510: 12. Bibcode:2010A&A...510A..43C. doi:10.1051/0004-6361/200913322. Retrieved 3 March 2020. (PDS data set)
  12. ^ a b c d "LCDB Data for (869) Mellena". Asteroid Lightcurve Database (LCDB). Retrieved 3 March 2020.
  13. ^ Owings, Larry E. (January 2011). "Lightcurves for 869 Mellena, 2375 Radek, and (19261) 1995 MB" (PDF). Minor Planet Bulletin. 38 (1): 9–10. Bibcode:2011MPBu...38....9O. ISSN 1052-8091.
  14. ^ Carbognani, Albino (January 2011). "Lightcurves and Periods of Eighteen NEAs and MBAs" (PDF). Minor Planet Bulletin. 38 (1): 57–63. Bibcode:2011MPBu...38...57C. ISSN 1052-8091.
edit