(192642) 1999 RD32

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(192642) 1999 RD32
1999rd32.jpg
Goldstone radar image showing the two lobes of suspected contact binary 1999 RD32.
Discovery[1]
Discovered by LINEAR (704)
Discovery date 8 September 1999
Designations
MPC designation (192642) 1999 RD32
Apollo Apollo
NEO, PHA[2]
Orbital characteristics[2]
Epoch 13 January 2016 (JD 2457400.5)
Uncertainty parameter 0
Observation arc 7702 days (21.09 yr)
Aphelion 4.6785 AU (699.89 Gm) (Q)
Perihelion 0.60926 AU (91.144 Gm) (q)
2.6439 AU (395.52 Gm) (a)
Eccentricity 0.76956 (e)
4.30 yr (1570.2 d)
311.50° (M)
0° 13m 45.372s / day (n)
Inclination 6.7925° (i)
310.06° (Ω)
299.87° (ω)
Earth MOID 0.0497973 AU (7.44957 Gm)
Jupiter MOID 0.669115 AU (100.0982 Gm)
Physical characteristics
Dimensions ~5 kilometers (3 mi)[3]
17.08 h (0.712 d)
17.08 hr[2][3][4]
~0.04[3]
16.3[2]

(192642) 1999 RD32, provisionally known as 1999 RD32, is a near-Earth asteroid and potentially hazardous object.[2] It was discovered on 8 September 1999 by Lincoln Near-Earth Asteroid Research (LINEAR) at an apparent magnitude of 18 using a 1.0-meter (39 in) reflecting telescope.[1]

With two precovery images from January 1995,[5] the asteroid has a very well determined orbit with an observation arc of 17 years.[2] It is known that 1999 RD32 passed 0.0093 AU (1,390,000 km; 860,000 mi) from Earth on 27 August 1969.[6] During the 1969 close approach the asteroid reached about apparent magnitude 8.8.[7] The similarly-sized 4179 Toutatis also reached that brightness in September 2004. 1999 RD32 passed less than 0.007 AU (1,000,000 km; 650,000 mi) from asteroid 29 Amphitrite on 17 January 1939.[2]

Arecibo radar observations on 5–6 March 2012 showed that 1999 RD32 is approximately 5 kilometers (3 mi) in diameter[3] and has an albedo of only a few percent.[3] The two visible lobes suggest that 1999 RD32 is a tight binary asteroid or contact binary.[3] About 10–15% of near-Earth asteroids larger than 200 meters are expected to be contact binary asteroids with two lobes in mutual contact.[8]

Close-approaches to Earth[6]
Date Distance from Earth
1969-08-27 0.0093 AU (1,390,000 km; 860,000 mi)
2012-03-14 0.1487 AU (22,250,000 km; 13,820,000 mi)
2042-03-11 0.1428 AU (21,360,000 km; 13,270,000 mi)
2046-09-04 0.1071 AU (16,020,000 km; 9,960,000 mi)

References[edit]

  1. ^ a b "MPEC 1999-R32 : 1999 RD32". IAU Minor Planet Center. 1999-09-11. Retrieved 2014-02-28.  (J99R32D)
  2. ^ a b c d e f g "JPL Small-Body Database Browser: 192642 (1999 RD32)" (2012-11-03 last obs and observation arc=17.8 years). Jet Propulsion Laboratory. Retrieved 7 April 2016. 
  3. ^ a b c d e f "(192642) 1999 RD32 Goldstone Radar Observations Planning". NASA/JPL Asteroid Radar Research. 2012-03-12. Retrieved 2014-02-28. 
  4. ^ Warner, Brian D.; Megna, Ralph (2012). "Lightcurve Analysis of NEA (192642) 1999 RD32". The Minor Planet Bulletin 39 (3): 154. Bibcode:2012MPBu...39..154W. 
  5. ^ "(192642) = 1999 RD32 Orbit" (2012-11-03 (arc=6515 days)). Minor Planet Center. Retrieved 2014-02-28. 
  6. ^ a b "JPL Close-Approach Data: 192642 (1999 RD32)" (2012-11-03 last obs and observation arc=17.8 years). Retrieved 2014-02-28. 
  7. ^ "1999RD32 Ephemerides for 25 August 1969 through 31 August 1969". NEODyS (Near Earth Objects – Dynamic Site). Retrieved 2014-02-28. 
  8. ^ Michael Busch (2012-03-12). "Near-Earth Asteroids and Radar Speckle Tracking" (PDF). Retrieved 2014-02-28. 

External links[edit]