2016 WF9
2016 WF9 (artist rendition) | |
Discovery [1][2] | |
---|---|
Discovered by | NEOWISE project |
Discovery site | NEOWISE |
Discovery date | 27 November 2016 |
Designations | |
Apollo · NEO · PHA [3] | |
Orbital characteristics [3] | |
Epoch 2457800.5 (2017-Feb-16.0) TDB[3] Reference: JPL 11 (heliocentric ecliptic J2000)[3] | |
Uncertainty parameter 5 | |
Observation arc | 111 days |
Aphelion | 4.759 AU[3] |
Perihelion | 0.9817 AU[3] |
2.870 AU[3] | |
Eccentricity | 0.6580[3] |
4.86 yr (1776 days)[3] | |
3.004 deg[3] | |
Inclination | 14.99 deg[3] |
125.4 deg[3] | |
342.4 deg[3] | |
Earth MOID | 0.014 AU |
Jupiter MOID | 0.52 AU[3] |
Jupiter Tisserand parameter | 2.893 (comet-like) |
Physical characteristics | |
Dimensions | 0.5–1.0 km (0.3–0.6 mi)[2] |
<0.05 (dark) | |
20+[4] | |
20.2[3] | |
|
2016 WF9 is an asteroid, classified as near-Earth object and potentially hazardous asteroid of the Apollo group.[3][4] The asteroid is somewhat dark, and possibly an extinct comet, but without the comet-like dust and gas cloud.[2] It was detected on 27 November 2016 by NEOWISE, the asteroid-and-comet-hunting portion of the Wide-Field Infrared Survey Explorer (WISE) mission.[2] According to NEOWISE, “2016 WF9 could have cometary origins. This object illustrates that the boundary between asteroids and comets is a blurry one; perhaps over time this object has lost the majority of the volatiles that linger on or just under its surface.”[5] 2016 WF9 is about 0.5–1.0 km (0.3–0.6 mi) across so is "relatively large" for a near-Earth object.[2]
2017 approach
2016 WF9 passed Earth on 25 February 2017 at a distance of 0.3407 AU (50,970,000 km; 31,670,000 mi) and is not considered a threat for the foreseeable future.[2][3] The 2017 approach did not bring it particularly close to Earth.[2] In December 1944 it passed about 0.19 AU (28,000,000 km; 18,000,000 mi) from Earth and in February 2149 it will pass about 0.06 AU (9,000,000 km; 5,600,000 mi) from Earth.[3]
Discovery
When 2016 WF9 was first announced and had a short insignificant 3 day observation arc, it was estimated to have a 7.6 year orbital period.[1] The preliminary orbit was also listed on the JPL Sentry Risk Table, but none of the virtual impact dates were before 2029.[6] As the observation arc became longer and the orbital parameters better constrained, it was removed from the Sentry Risk Table on 20 December 2016.[7] With a 111-day observation arc, it is now known that it has a 4.86 year orbital period and currently stays inside the orbit of Jupiter.[3]
A simulation of 2016 WF9's dynamics over a period of 100 million days (~274,000 years) found that it had roughly a 60% chance of originating from the outer solar system as a long-period comet.[8]
See also
References
- 1 2 "MPEC 2016-W125: 2016 WF9". IAU Minor Planet Center. 2016-11-30. Retrieved 2017-02-02. (K16W09F)
- 1 2 3 4 5 6 7 Agle, DC; Cantillo, Laurie; Brown, Dwayne (29 December 2016). "NASA's NEOWISE Mission Spies One Comet, Maybe Two". NASA. Retrieved 29 December 2016.
- 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Park, Ryan S.; Chamberlin, Alan B. (30 December 2016). "JPL Small-Body Database Browser (2016 WF9)". JPL. Retrieved 30 December 2016.
- 1 2 MPC
- ↑ Williams, Matt (30 December 2016). "NASA’S NEOWISE Missions Spots New Comets". Universe Today. Retrieved 31 December 2016.
- ↑ "Tracking News". hohmanntransfer. 2016-12-01. Retrieved 2017-02-02.
- ↑ "Date/Time Removed". NASA/JPL Near-Earth Object Program Office. Retrieved 2017-02-02.
- ↑ Odasso, Alessandro (9 January 2017). "2016 WF9 - a simulation based on Jan 5th orbital params". odassoastro.blogspot.it. Retrieved 9 January 2017.
External links
- 2016 WF9 at the IAU Minor Planet Center
- 2016 WF9 at the JPL Small-Body Database