893 Leopoldina
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| Discovery[1] | |
|---|---|
| Discovered by | M. F. Wolf |
| Discovery site | Heidelberg Obs. |
| Discovery date | 31 May 1918 |
| Designations | |
| (893) Leopoldina | |
Named after | Academy of Sciences Leopoldina (Germany's nat'l academy)[2] |
| A918 KD · 1935 OL 1918 DS | |
| main-belt[1][3] · (outer) background[4][5] | |
| Orbital characteristics[3] | |
| Epoch 31 May 2020 (JD 2459000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 101.67 yr (37,134 d) |
| Aphelion | 3.5069 AU |
| Perihelion | 2.6027 AU |
| 3.0548 AU | |
| Eccentricity | 0.1480 |
| 5.34 yr (1,950 d) | |
| 291.98° | |
| 0° 11m 4.56s / day | |
| Inclination | 17.025° |
| 144.94° | |
| 222.40° | |
| Physical characteristics | |
| Dimensions | 82.8 km × 59.8 km[5] |
| 14.115±0.003 h[9][a] | |
| 9.6[1][3] | |
893 Leopoldina (prov. designation: A918 KD or 1918 DS) is a large and elongated background asteroid from the outer regions of the asteroid belt. It was discovered by German astronomer Max Wolf at the Heidelberg Observatory on 31 May 1918.[1] The dark carbonaceous C-type asteroid has a rotation period of 14.1 hours and measures approximately 76 kilometers (47 miles) in diameter. It was named for Germany's national academy, the Academy of Sciences Leopoldina in Halle.[2]
Leopoldina 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 outer asteroid belt at a distance of 2.6–3.5 AU once every 5 years and 4 months (1,950 days; semi-major axis of 3.05 AU). Its orbit has an eccentricity of 0.15 and an inclination of 17° with respect to the ecliptic.[3] The body's observation arc begins with its official discovery observation at Heidelberg Observatory on 31 May 1918.[1]
Physical characteristics
In the Tholen classification, Leopoldina's asteroid spectral type is closest to that of an X-type, and somewhat similar to that of a dark F-type asteroid (XF), while in both the Tholen- and SMASS-like taxonomy of the Small Solar System Objects Spectroscopic Survey (S3OS2), it is a common carbonaceous C-type asteroid.[3][5][10]
Naming
This minor planet was named for Germany's national academy, the Academy of Sciences Leopoldina (German: Carolinisch-Leopoldinische Akademie der Naturforscher) in Halle, Saxony-Anhalt. The naming citation was mentioned in The Names of the Minor Planets by Paul Herget in 1955 (H 86).[2]
Rotation period
In April 2008, a rotational lightcurve of Leopoldina was obtained from photometric observations by Brian Warner at the Palmer Divide Observatory (716) in Colorado. Analysis gave a classically shaped bimodal lightcurve with a well-defined rotation period of 14.115±0.003 hours and a brightness variation of 0.18±0.02 magnitude (U=3).[9][a] The result supersedes Warner's previous observation from August 2005, which determined a period of 10.51±0.01 hours and an amplitude of 0.35±0.02 magnitude (U=2).[11]
Diameter and albedo
According to the survey 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), Leopoldina measures (75.55±0.97), (76.14±4.5) and (85.992±0.577) kilometers in diameter and its surface has an albedo of (0.051±0.001), (0.0497±0.006) and (0.039±0.007), respectively.[6][7][8] The Collaborative Asteroid Lightcurve Link adopts the results obtained by IRAS, that is, an albedo of 0.0497 and a diameter of 76.14 kilometers based on an absolute magnitude of 9.47.[12]
Alternative mean-diameter measurements published by the WISE team include (57.900±15.097 km), (68.91±23.37 km), (76±8 km), (76.1±15.2 km) and (76.623±2.309 km) with albedos in the range of 0.049 to 0.06.[5][12]
Three asteroid occultation were obtained on 29 January 1996, 30 August 2010 and 16 May 2015. They gave a best-fit ellipse dimension of 79.0 × 72.0 kilometers, 82.8 × 59.8 kilometers (best), and 75.0 × 75.0 kilometers, respectively. These timed observations are taken when the asteroid passes in front of a distant star.[5]
