1175 Margo
Stony background asteroid
From Wikipedia, the free encyclopedia
1175 Margo, provisional designation 1930 UD, is a stony background asteroid from the outermost regions of the asteroid belt, approximately 24 kilometers in diameter. It was discovered on 17 October 1930, by astronomer Karl Reinmuth at the Heidelberg-Königstuhl State Observatory in southwest Germany.[15] The meaning of the asteroids's name is unknown.[2]
_Margo.png)
Modelled shape of Margo from its lightcurve | |
| Discovery[1] | |
|---|---|
| Discovered by | K. Reinmuth |
| Discovery site | Heidelberg Obs. |
| Discovery date | 17 October 1930 |
| Designations | |
| (1175) Margo | |
Named after | unknown[2] |
| 1930 UD · 1953 VK 1957 KU · A907 VA | |
| main-belt · (outer)[1][3] background[4] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 109.91 yr (40,146 days) |
| Aphelion | 3.4345 AU |
| Perihelion | 2.9979 AU |
| 3.2162 AU | |
| Eccentricity | 0.0679 |
| 5.77 yr (2,107 days) | |
| 61.257° | |
| 0° 10m 15.24s / day | |
| Inclination | 16.307° |
| 237.19° | |
| 102.79° | |
| Physical characteristics | |
| Dimensions | 22.99±0.85 km[5] 24.266±0.276 km[6] 25.394±0.250 km[7] 58.29 km (calculated)[3] |
| 6.01±0.02 h[8] 6.01±0.03 h[9] 6.0136±0.0002 h[9] 6.01375±0.00005 h[10] 6.015±0.001 h[11] 6.017±0.001 h[12] 11.99±0.03 h[13] | |
| 0.057 (assumed)[3] 0.2409±0.0329[7] 0.249±0.042[6] 0.302±0.026[5] | |
| S[14] · C (assumed)[3] | |
| 9.9[3] · 10.0[1] · 10.06±0.23[14] · 10.20[5][7] | |
Orbit and classification
Margo is a non-family asteroid from the main belt's background population.[4] It orbits the Sun in the outermost asteroid belt at a distance of 3.0–3.4 AU once every 5 years and 9 months (2,107 days; semi-major axis of 3.22 AU). Its orbit has an eccentricity of 0.07 and an inclination of 16° with respect to the ecliptic.[1]
The body's observation arc begins with its first identification as A907 VA at Heidelberg in November 1907, almost 23 years prior to its official discovery observation.[15]
Physical characteristics
Margo has been characterized as a stony S-type asteroid by Pan-STARRS photometric survey.[14] Conversely, the Collaborative Asteroid Lightcurve Link (CALL) assumes it to be a carbonaceous C-type.[3]
Rotation period and poles
In November 2005, a rotational lightcurve of Margo was obtained from photometric observations by astronomers Raymond Poncy (177), Gino Farroni, Pierre Antonini, Donn Starkey (H63) and Raoul Behrend. Lightcurve analysis gave a well-defined rotation period of 6.0136 hours with a brightness amplitude of 0.31 magnitude (U=3).[9] Since then, several other, lower-rated lightcurves have been published (U=3-/2+/2+/2/2).[8][9][11][12][13]
In 2016, the asteroid lightcurve has also been modeled using photometric data from various sources. It gave a concurring period of 6.01375 hours and two spin axis in ecliptic coordinates of (184.0°, −43.0°) and (353.0°, −17.0°).[10]
Diameter and albedo
According to the surveys carried out by the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Margo measures between 22.99 and 25.394 kilometers in diameter and its surface has an albedo between 0.2409 and 0.302.[5][6][7] CALL assumes a standard albedo for carbonaceous asteroids of 0.057 and consequently calculates a much larger diameter of 58.29 kilometers based on an absolute magnitude of 9.9.[3]
Naming
This minor planet was named by the discoverer Karl Reinmuth. Any reference of its name to a person or occurrence is unknown.[2]
Unknown meaning
Among the many thousands of named minor planets, Margo is one of 120 asteroids, for which no official naming citation has been published. All of these low-numbered asteroids have numbers between 164 Eva and 1514 Ricouxa and were discovered between 1876 and the 1930s, predominantly by astronomers Auguste Charlois, Johann Palisa, Max Wolf and Karl Reinmuth.[16]
