(332446) 2008 AF4

Last updated

(332446) 2008 AF4
Discovery [1]
Discovered by LINEAR
Discovery site Lincoln Lab's ETS
Discovery date10 January 2008
Designations
(332446) 2008 AF4
2008 AF4
NEO  · Apollo  · PHA [1]
Orbital characteristics [1]
Epoch 4 September 2017 (JD 2458000.5)
Uncertainty parameter 0
Observation arc 13.78 yr (5,032 days)
Aphelion 1.9506 AU
Perihelion 0.8144 AU
1.3825 AU
Eccentricity 0.4109
1.63 yr (594 days)
8.0690°
0° 36m 22.68s / day
Inclination 8.9193°
109.38°
293.39°
Earth  MOID 0.0025 AU ·1 LD
Physical characteristics
Dimensions390 m
Mass 8.3×1010  kg
19.7 [1]

    (332446) 2008 AF4 is a sub-kilometer asteroid, classified as near-Earth object and potentially hazardous asteroid of the Apollo group, which was listed on the Sentry Risk Table in January 2008 with a Torino Scale rating of 1. [2] The asteroid showed a 1 in 71,000 chance of impact on 9 January 2089. [2] It was briefly downgraded to Torino Scale 0 in February 2008, but still showed a cumulative 1 in 53,000 chance of an impact. [3] In March it was back at Torino Scale 1 with a 1 in 28,000 chance of impact on 9 January 2089. [4] By mid April 2008, it was back to Torino Scale 0. It was removed from the Sentry Risk Table on 19 December 2009. [5]

    Contents

    2183 passage

    2008 AF4 may pass as close as 0.002  AU (300,000  km ; 190,000  mi ) from Earth on 12 January 2183. [6] But the nominal solution shows the asteroid passing 0.009 AU (1,300,000 km; 840,000 mi) from Earth. [6]

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    References

    1. 1 2 3 4 "JPL Small-Body Database Browser: 2008 AF4" . Retrieved 20 April 2016.
    2. 1 2 "WayBack Machine archive from 1 January 2008". Wayback Machine. 15 January 2008. Archived from the original on 15 January 2008. Retrieved 7 September 2013.
    3. "WayBack Machine archive from 14 February 2008". Wayback Machine. 14 February 2008. Archived from the original on 14 February 2008. Retrieved 7 September 2013.
    4. "WayBack Machine archive from 16 March 2008". Wayback Machine. 16 March 2008. Archived from the original on 16 March 2008. Retrieved 7 September 2013.
    5. "Date/Time Removed". NASA/JPL Near-Earth Object Program Office. Archived from the original on 2 June 2002. Retrieved 6 November 2011.
    6. 1 2 "JPL Close-Approach Data: 332446 (2008 AF4)" (last observation: 2013-03-19; arc: 10.8 years). Retrieved 7 September 2013.