Discovery date 3 August 2000 Alternative names 2000 PH5 Observation arc 1826 days (5.00 yr) Orbits Sun | MPC designation 54509 Minor planet category Apollo NEO Discovered 3 August 2000 Discovery site Socorro | |
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Named after Yarkovsky–O'Keefe–Radzievskii–Paddack effect Discoverer Lincoln Near-Earth Asteroid Research Similar 4769 Castalia, 2101 Adonis, C/1911 O1, 588 Achilles, 2002 VE68 | ||
54509 YORP (2000 PH5) is an Earth co-orbital asteroid discovered on August 3, 2000 by the Lincoln Laboratory Near-Earth Asteroid Research (LINEAR) Team at Socorro. Measurements of the rotation rate of this object provided the first observational evidence of the YORP effect, hence the name of the asteroid. The asteroid's rate of rotation is increasing at the rate of (2.0 ± 0.2) × 10−4 deg/day2 which between 2001 and 2005 caused the asteroid to rotate about 250° further than its spin rate in 2001 would have predicted. Simulations of the asteroid suggest that it may reach a rotation period of ~20 seconds near the end of its expected lifetime. The simulations also ruled out the possibility that close encounters with the Earth have been the cause of the increased spin rate.
On January 2, 2104, asteroid YORP will pass 0.00526 AU (787,000 km; 489,000 mi) from Earth.