Astronomy:132 Aethra
.png) Lightcurve-based 3D-model of Aethra | |
| Discovery | |
|---|---|
| Discovered by | James C. Watson |
| Discovery date | 13 June 1873 |
| Designations | |
| (132) Aethra | |
| Pronunciation | /ˈiːθrə/[1] |
| Named after | Aethra |
| A873 LA; 1922 XB; 1949 MD; 1953 LF | |
| Minor planet category | Mars crosser |
| Orbital characteristics[2] | |
| Epoch 31 July 2016 (JD 2457600.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 142.50 yr (52049 d) |
| |{{{apsis}}}|helion}} | 3.6250 astronomical unit|AU (542.29 Gm) |
| |{{{apsis}}}|helion}} | 1.5895 AU (237.79 Gm) |
| 2.6073 AU (390.05 Gm) | |
| Eccentricity | 0.39036 |
| Orbital period | 4.21 yr (1537.7 d) |
| Average Orbital speed | 17.72 km/s |
| Mean anomaly | 38.271° |
| Mean motion | 0° 14m 2.796s / day |
| Inclination | 24.997° |
| Longitude of ascending node | 258.408° |
| 255.216° | |
| Physical characteristics | |
| Dimensions | 35.83±6.59 km[3] 42.87±1.6 km[2] |
| Mass | (0.41±2.71)×1018 kg[3] |
| Rotation period | 5.1684 h (0.21535 d)[2] |
| Geometric albedo | 0.1990±0.015[2] |
| M | |
| Absolute magnitude (H) | 9.38[2] |
Aethra (minor planet designation: 132 Aethra) is a metallic asteroid and Mars-crosser on an eccentric orbit from the asteroid belt. It measures approximately 40 kilometers in diameter.
It was discovered by James Craig Watson in 1873 and is the first such Mars-crosser asteroid to be identified. As a Mars-crosser asteroid, Aethra is the lowest numbered asteroid to not have proper orbital elements due to recurring perturbations by Mars. It has a rather eccentric orbit that sometimes brings it closer to the Sun than the planet Mars.
With an original observation arc of only 22 days, 132 Aethra was a lost asteroid between 1873 and 1922.[4][5]
The varying light curve of the asteroid implies an elongated or irregular shape for its body.
It is named after Aethra, the mother of Theseus in Greek mythology.
References
- ↑ Noah Webster (1884) A Practical Dictionary of the English Language
- ↑ 2.0 2.1 2.2 2.3 2.4 "JPL Small-Body Database Browser: 132 Aethra". https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=132. Retrieved 12 May 2016.
- ↑ 3.0 3.1 Carry, B. (December 2012). "Density of asteroids". Planetary and Space Science 73 (1): 98–118. doi:10.1016/j.pss.2012.03.009. Bibcode: 2012P&SS...73...98C. See Table 1.
- ↑ Herget, Paul (1938). "The orbit and perturbations of (132) Aethra". Astronomical Journal 47 (1081): 17–23. doi:10.1086/105455. Bibcode: 1938AJ.....47...17H.
- ↑ Fred William Price (2000). The Planet Observer's Handbook. Cambridge University Press. p. 192. ISBN 978-0-521-78981-3. https://archive.org/details/planetobserversh00pric.
External links
- 132 Aethra at AstDyS-2, Asteroids—Dynamic Site
- 132 Aethra at the JPL Small-Body Database
 |  |
