1139 Atami

1139 Atami
Discovery
Discovered byO. Oikawa
K. Kubokawa
Discovery siteTokyo Astronomical Obs. (389)
Discovery date1 December 1929
Designations
(1139) Atami
PronunciationJapanese: [atami]
Named after
Atami (Japanese city)
1929 XE
Mars-crosser
Orbital characteristics
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc87.50 yr (31,960 days)
Aphelion2.4451 AU
Perihelion1.4505 AU
1.9478 AU
Eccentricity0.2553
2.72 yr (993 days)
110.80°
0° 21m 45.36s / day
Inclination13.087°
213.35°
206.62°
Known satellites1
Earth MOID0.4722 AU · 184 LD
Mars MOID0.0298 AU
Physical characteristics
Dimensions8.24±0.82 km
9.35 km (calculated)
15 h
20 h
24 h
27.43±0.05
27.446±0.001 h
27.45±0.01 h
27.45±0.05 h
27.472±0.002 h
27.56±0.01 h
0.20 (assumed)
0.258±0.052
S (Tholen) · S (SMASS)
S
B–V = 0.920
U–B = 0.497
12.51 · 12.59±0.37 · 12.86±0.02

1139 Atami, provisional designation 1929 XE, is a stony asteroid and sizable Mars-crosser, as well as a synchronous binary system near the innermost region of the asteroid belt, approximately 9 kilometers in diameter. It was discovered on 1 December 1929, by Japanese astronomers Okuro Oikawa and Kazuo Kubokawa at the Tokyo Astronomical Observatory (389) near Tokyo. It was named after the Japanese city of Atami. It has the lowest Minimum orbit intersection distance (MOID) to Mars of any asteroid as large as it, its orbit intersecting only 0.03 astronomical units from the planet.