2009 DD45 is a very small Apollo asteroid that passed near Earth at an altitude of 63,500 km (39,500 mi) on 2 March 2009 at 13:44 UTC. It was discovered by Australian astronomers with the Siding Spring Survey at the Siding Spring Observatory on 27 February 2009, only three days before its closest approach to the Earth.[4][5] Its estimated diameter is between 15 and 23 metres.[2] This is about the same size as a hypothetical object that could have caused the Tunguska event in 1908.[6]
Discovery[1] | |
---|---|
Discovered by | SSS |
Discovery site | Siding Spring Obs. |
Discovery date | 27 February 2009 |
Designations | |
2009 DD45 | |
NEO · Apollo[1][2] | |
Orbital characteristics[2] | |
Epoch 31 May 2020 (JD 2459000.5) | |
Uncertainty parameter 4[2] · 2[1] | |
Observation arc | 7 days |
Aphelion | 1.4952 AU |
Perihelion | 0.9868 AU |
1.2410 AU | |
Eccentricity | 0.2048 |
1.38 yr (505 d) | |
39.793° | |
0° 42m 46.8s / day | |
Inclination | 13.743° |
161.92° | |
13.919° | |
Earth MOID | 0.000339 AU (0.132 LD) |
Physical characteristics | |
Mean diameter | 19±4 m (est. at 0.36)[2] |
1.2 h (poor)[2][3] | |
0.36 (est.)[2] | |
SMASS = S[2] | |
25.8[1][2] | |
BBC News Online cites the minimum distance as 72,000 km (45,000 mi) (about 1/5 lunar distances).[6][7] 2009 DD45 passed farther away (40 thousand miles versus 4 thousand miles) but was substantially larger than 2004 FU162, a small asteroid about 6 m (20 ft) across which came within about 6,500 km (4,000 mi) in 2004,[6] and is more similar in size to 2004 FH. With an observation arc of 7 days and an uncertainty parameter of 3, the asteroid will make its next close encounter with Earth on 29 February 2056 and then potentially around 3 March 2067.[2]