1009 Sirene

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1009 Sirene
Discovery[1]
Discovered by Karl Wilhelm Reinmuth
Heidelberg (024)
Discovery date October 31, 1923
Designations
MPC designation 1923 PE
Minor planet category Mars-crossing[1]
Orbital characteristics[1]
Epoch 2014-May-23
Aphelion 3.8201 AU (Q)
Perihelion 1.4238 AU (q)
2.622 AU (a)
Eccentricity 0.45696
4.25 yr
92.974° (M)
Inclination 15.7816°
229.47°
186.39°
Physical characteristics
Dimensions 5–10 km[2]
13.8[1]

1009 Sirene is a Mars-crosser asteroid. It was discovered by Karl Wilhelm Reinmuth on October 31, 1923, and observed for 4 months.[3] Its provisional designation was 1923 PE[1] and it was named after the mythological Sirens. It became a lost asteroid until it was recovered in 1982 from exposures on the 48-inch (120 cm) Schmidt at Palomar Observatory.[4]

Sirene's semi-major axis is 2.62 AU, well beyond that of Mars, but its highly eccentric orbit crosses Mars', allowing close approaches of the planet. On 8 June 1949 the asteroid passed 0.049 AU (7,300,000 km; 4,600,000 mi) from Mars.[1] With an absolute magnitude of 13.8,[1] the asteroid is about 5–10 km in diameter.[2]

References[edit]

  1. ^ a b c d e f g "JPL Close-Approach Data: 1009 Sirene (1923 PE)". 2014-06-01 last obs. Retrieved 2014-06-23. 
  2. ^ a b "Absolute Magnitude (H)". NASA/JPL. Retrieved 2014-06-09. 
  3. ^ "(1009) Sirene = A923PE". IAU Minor Planet Center. Retrieved 2014-06-23. 
  4. ^ (1009) Sirene Gibson, J.; Kristensen, L. K. IAU Circ., 3714, 1 (1982). Edited by Marsden, B. G.