|Discovered by||H. E. Holt
N. G. Thomas
|Discovery site||Palomar Obs.|
|Discovery date||31 March 1989|
|MPC designation||(4581) Asclepius|
|Apollo · NEO · PHA |
|Orbital characteristics |
|Epoch 28 May 2014 (JD 2456805.5)|
|Uncertainty parameter 0|
|Observation arc||27.27 yr (9,959 days)|
|1.03 yr (378 days)|
|0° 57m 12.24s / day|
|Earth MOID||0.0036 AU|
|Dimensions||300 m|
4581 Asclepius (ə-SKLEE-pee-əs), provisional designation 1989 FC, is a sub-kilometer-sized asteroid, classified as near-Earth object and potentially hazardous asteroid of the Apollo group that makes close orbital passes with Earth. Discovered on 31 March 1989, by American astronomers Henry Holt and Norman Thomas at Palomar Observatory, Asclepius is named after the Greek demigod of medicine and healing.
Asclepius passed by Earth on 22 March 1989, at a distance of 0.00457 AU (684,000 km; 425,000 mi). Although this exceeds the Moon's orbital radius, the close pass received attention at that time, especially since the asteroid passed through the exact position of Earth only six hours earlier. "On the cosmic scale of things, that was a close call," said Dr. Henry Holt. Geophysicists estimate that collision with Asclepius would release energy comparable to the explosion of a 600 megaton atomic bomb. The asteroid was discovered 31 March 1989, nine days after its closest approach to the Earth.
Subsequent discoveries revealed that a whole class of such objects exists. Close approaches by objects the size of Asclepius pass by every two or three years, undetected until the start of computerized near-Earth object searches.
On 24 March 2051, the asteroid will pass 0.0123 AU (1,840,000 km; 1,140,000 mi) from the Earth. It will be the eighth pass of less than 30 Gm in this century. JPL shows that the uncertainty region of the asteroid will cause it to mostly likely pass from 0.02 AU to 0.17 AU from the Earth in 2135.
- "JPL Small-Body Database Browser: 4581 Asclepius (1989 FC)" (2016-07-06 last obs.). Jet Propulsion Laboratory. Retrieved 13 March 2017.
- Schmadel, Lutz D. (2007). Dictionary of Minor Planet Names – (4581) Asclepius. Springer Berlin Heidelberg. p. 394. ISBN 978-3-540-00238-3. Retrieved 13 March 2017.
- "4581 Asclepius (1989 FC)". Minor Planet Center. Retrieved 13 March 2017.
- "JPL Close-Approach Data: 4581 Asclepius (1989 FC)" (2015-08-10 last obs (arc=26.36 years)). Retrieved 2016-01-09.
- "NEODyS-2 Close Approaches for (4581) Asclepius". Near Earth Objects - Dynamic Site. Retrieved 2011-11-08.
- "Asteroid's Passing a 'Close Call' for Earth, NASA Says". Los Angeles Times. April 20, 1989. Retrieved 2010-05-07.
- Gilchrist, Tom (November 2008). "Effects of an impact event: an analysis of asteroid 1989FC". Geoverse: e-journal of Undergraduate Research in Geography. ISSN 1758-3411. Retrieved 2010-05-07.
- Brian G. Marsden (1998-03-29). "How the Asteroid Story Hit: An Aastronomer Reveals How a Discovery Spun Out of Control". Minor Planet Center and Boston Globe newspaper. Retrieved 2011-11-14.
- Asteroid Lightcurve Database (LCDB), query form (info)
- Dictionary of Minor Planet Names, Google books
- Discovery Circumstances: Numbered Minor Planets (1)-(5000) – Minor Planet Center
- 4581 Asclepius at the JPL Small-Body Database