1293 Sonja

1293 Sonja

Discovery [1]

Discovered by
E. Delporte

Discovery site
Uccle Obs.

Discovery date
26 September 1933

Designations

MPC designation
1293 Sonja

Named after

unknown [2]

Alternative names

1933 SO

Minor planet category

Mars-crosser [1][3][4]

Orbital characteristics [1]

Epoch 16 February 2017 (JD 2457800.5)

Uncertainty parameter 0

Observation arc
83.28 yr (30,419 days)

Aphelion
2.8410 AU

Perihelion
1.6140 AU

Semi-major axis

2.2275 AU

Eccentricity
0.2754

Orbital period

3.32 yr (1,214 days)

Mean anomaly

45.125°

Mean motion

0° 17m 47.4s / day

Inclination
5.3636°

Longitude of ascending node

236.38°

Argument of perihelion

99.857°

Earth MOID
0.6163 AU

Physical characteristics

Dimensions
7000365000000000000♠3.65±0.45 km[5]
7.23 km (derived)[4]
7000780000000000000♠7.80±0.7 km (IRAS:3)[6]

Rotation period

7000287600000000000♠2.876±0.001 h[a]
7000287680000000000♠2.8768±0.0003 h[b][c]
7000287797000000000♠2.87797±0.00002 h[d][e]
7000287800000000000♠2.878±0.001 h[7]
7000287850000000000♠2.8785±0.0001 h[8]
7000287900000000000♠2.879±0.001 h[f][g]
7000287900000000000♠2.879±0.002 h[9]
7000288100000000000♠2.881±0.002 h[h]

Geometric albedo

0.1226 (derived)[4]
6999459800000000000♠0.4598±0.095 (IRAS:3)[6]
6999529000000000000♠0.529±0.133[5]

Spectral type

SMASS = Sq [1] · S [4]

Absolute magnitude (H)

12.00[6] · 13.50[5] · 13.6[1][4] · 7001138600000000000♠13.86±0.32[10]

1293 Sonja, provisional designation 1933 SO, is a stony asteroid and bright Mars-crosser from the innermost regions of the asteroid belt, approximately 7 kilometers in diameter. It was discovered on 26 September 1933, by Belgian astronomer Eugène Delporte at Uccle Observatory in Belgium.[3] Two nights later, Sonja was independently discovered by Soviet astronomer Grigory Neujmin at Simeiz on the Crimean peninsula. The origin of the asteroid’s name is unknown.[2]
Description[edit]
In the SMASS taxonomy, Sonja is classified as a Sq-type, an intermediary between the abundant S and rather rare Q-type asteroids. It orbits the Sun at a distance of 1.6–2.8 AU once every 3 years and 4 months (1,214 days). Its orbit has an eccentricity of 0.28 and an inclination of 5° with respect to the ecliptic.[1] Sonja’s observation arc begins with its official discovery observation at Uccle, as no