64 Angelina
 Lightcurve-based 3D-model ofAngelina | |
| Discovery | |
|---|---|
| Discovered by | Ernst Wilhelm Tempel |
| Discovery date | March 4, 1861 |
| Designations | |
| (64) Angelina | |
| Pronunciation | /ˌændʒəˈliːnə/AN-jə-LEE-nə[1] |
| Main belt[2] | |
| Adjectives | Angelinian (/ˌændʒəˈlɪniən/AN-jə-LIN-nee-ən) |
| Orbital characteristics | |
| EpochDecember 31, 2006 (JD2454100.5) | |
| Aphelion | 451.375Gm(3.017AU) |
| Perihelion | 351.784 Gm (2.352 AU) |
| 401.580 Gm (2.684 AU) | |
| Eccentricity | 0.124 |
| 1606.452 d (4.40yr) | |
| 107.758° | |
| Inclination | 1.308° |
| 309.285° | |
| 179.641° | |
| Physical characteristics | |
| Dimensions | 48 x 53 km[3] 52 ± 10 km[4] 60 x 53 x 45 km[5] |
| Mass | 1.5×1017kg (assumed)[6] |
| 8.752 hr[2](0.365 d) | |
| 0.28 [7] 0.157 (IRAS)[2] | |
| E | |
| 7.67 [2] | |
64 Angelinais anasteroidfrom the central region of theasteroid belt,approximately 50 kilometers in diameter. It is an unusually bright form ofE-type asteroid.
Discovery and naming
[edit]Angelina was discovered on March 4, 1861, by a prolificcometdiscoverer,E. W. Tempel,observing fromMarseilles,France. It was the first of his five asteroid discoveries.
The naming of Angelina caused some controversy. It was chosen byBenjamin Valz,director of theMarseilles Observatory,in honour of the astronomical station of that name operated byBaron Franz Xaver von Zachon the mountains above the city. At the time, asteroids were supposed to receive names from classical mythology, and several astronomers protested the choice. Tempel noted that if the second 'n' were removed, the complaints would be satisfied (referring toAngelia,a minor Greek deity). However, Valz's choice stayed.[8]
Physical characteristics
[edit]Angelina is an uncommon form ofE-type asteroid;it is the third largest E-type after44 Nysaand55 Pandora,and has an exceptionally highalbedo.[9]As of 1991, it is thought to have an average radius of about 30 kilometers (19 mi).[10]Back when asteroids were generally assumed to have lowalbedos,Angelina was thought to be the largest of this class, but modern research has shown that its diameter is only a quarter of what was previously assumed, an error caused by its exceptional brightness. Traditional calculations had suggested that since Angelina has anabsolute magnitudeof 7.7 and analbedoof 0.15,[2]its diameter would have been around 100 km. However, a 2004occultationshowed a cross-sectional profile of only 48x53 km.[3]Angelina was observed byAreciboradarin January 2010.[5]
References
[edit]- ^"Angelina".Oxford English Dictionary(Online ed.).Oxford University Press.(Subscription orparticipating institution membershiprequired.)
- ^abcde"JPL Small-Body Database Browser: 64 Angelina".Retrieved5 September2010.
2010-06-01 last obs
- ^abDavid Dunham (2–3 July 2004)."IOTA Meeting, Apple Valley, Calif".IOTA.Retrieved21 February2007.
- ^Ďurech, Josef; Kaasalainen, Mikko; Herald, David; Dunham, David; Timerson, Brad; Hanuš, Josef; et al. (2011)."Combining asteroid models derived by lightcurve inversion with asteroidal occultation silhouettes"(PDF).Icarus.214(2): 652–670.arXiv:1104.4227.Bibcode:2011Icar..214..652D.doi:10.1016/j.icarus.2011.03.016.S2CID119271216.Archived fromthe original(PDF)on 3 March 2016.Retrieved26 January2012.
- ^abShepard, Michael K.; Harris, Alan W.; Taylor, Patrick A.; Clark, Beth Ellen; Ockert-Bell, Maureen; Nolan, Michael C.; et al. (2011)."Radar observations of Asteroids 64 Angelina and 69 Hesperia"(PDF).Icarus.215(2): 547–551.arXiv:1104.4114.Bibcode:2011Icar..215..547S.doi:10.1016/j.icarus.2011.07.027.S2CID119290080.
- ^Using a spherical radius of 26 km;volume of a sphere* density of 2 g/cm3yields a mass (m=d*v) of 1.472E+17 kg
- ^Morrison, D.; Chapman, C. R. (1976). "Radiometric diameters for an additional 22 asteroids".Astrophysical Journal.204:934–939.Bibcode:1976ApJ...204..934M.doi:10.1086/154242.
- ^Schmadel, Lutz D. (2003).Dictionary of Minor Planet Names.Springer Science & Business Media. p. 21.ISBN978-3-540-00238-3.
- ^Kiselev, N.N; Shakhovskoy, N.M; Efimov, Yu.S (1996), "On the Polarization Opposition Effect of E-Type Asteroid 64 Angelina",Icarus,120(2): 408,Bibcode:1996Icar..120..408K,doi:10.1006/icar.1996.0060
- ^Lionel Wilson and Klaus Keil -Explosive Eruptions on Asteroids: The Missing Basalts on the Aubrite Parent Body- Abstracts of the Lunar and Planetary Science Conference, volume 22, page 1515, (1991)
External links
[edit]- 2004 Angelina occultation(cross-sectional profile of 48x53 km)
- 64 AngelinaatAstDyS-2, Asteroids—Dynamic Site
- 64 Angelinaat theJPL Small-Body Database
