311P/PanSTARRS
 P/2013 P5 as captured by the Hubble Space Telescope | |
| Discovery | |
|---|---|
| Discovered by | Pan-STARRS |
| Discovery date | 27 August 2013 |
| Designations | |
| asteroid Main-belt comet | |
| Orbital characteristics[1] | |
| Epoch 2013-Sep-07 | |
| Aphelion | 2.441 AU |
| Perihelion | 1.936 AU |
| 2.189 AU | |
| Eccentricity | 0.1152 |
| 3.24 yr (1182.638d) | |
Average orbital speed | 0.3044°/d |
| 292.8° | |
| Inclination | 4.969° |
| 279.3° | |
| 144.2° | |
| Physical characteristics | |
| Dimensions | ~480 meters (1,570 ft) [2] |
Mean density | 3300±200 kg m3 [3] |
| ~0.240 meters (9.4 in) per second | |
P/2013 P5 is an asteroid (or main-belt comet) discovered by the Pan-STARRS telescope on 27 August 2013.[4] Observations made by the Hubble Space Telescope revealed that it has six comet-like tails.[5] The tails are suspected to be streams of material ejected by the asteroid as a result of a rubble pile asteroid spinning fast enough to remove material from it.[2]
Three dimensional models constructed by Jessica Agarwal of the Max Planck Institute for Solar System Research in Lindau, Germany, showed that the tails could have formed by a series of periodic impulsive dust-ejection events,[6] radiation pressure from the sun then stretched the dust into streams.[7]
Characteristics
The asteroid has a radius of about 240 meters (790 ft).[2] The first images taken by Pan-STARRS revealed that the object had a unusual appearance, asteroids generally appear as small points of light, but P/2013 P5 was identified as a fuzzy-looking object by astronomers.[8] The multiple tails were observed by the Hubble Space Telescope on 10 September 2013, Hubble later returned to the asteroid on 23 September, its appearance had totally changed. It looked as if the entire structure had swung around.[9] The comet-like appearance has resulted in the asteroid being named as a comet.
References
- ^ "JPL Small-Body Database Browser: P/2013 P5 (PANSTARRS)". 2013-11-07 last obs. Retrieved 2013-11-09.
{{cite web}}: Check date values in:|date=(help) - ^ a b c Jewitt, David; Jessica, Agarwal; Stephen, Larson (2013). "The Extraordinary Multi-Tailed Main-Belt Comet P/2013 P5". The Astronomical Journal. arXiv:1311.1483. Bibcode:2013arXiv1311.1483J.
- ^ "The Extraordinary Multi-Tailed Main-Belt Comet P/2013 P5" (PDF). Spacetelescope.
- ^ "When is a comet not a comet?". Spacetelescope. 7 November 2013.
{{cite news}}: Cite has empty unknown parameter:|1=(help) - ^ "NASA's Hubble Sees Asteroid Spouting Six Comet-Like Tails". Hubblesite. 7 November 2013.
{{cite journal}}: Cite journal requires|journal=(help) - ^ "She calculated that dust-ejection events occurred on April 15, July 18, July 24, Aug. 8, Aug. 26 and Sept. 4"
- ^ "NASA's Hubble Sees Asteroid Spouting Six Comet-Like Tails". Hubblesite. 7 November 2013.
{{cite journal}}: Cite journal requires|journal=(help) - ^ "When is a comet not a comet?". ESA. 7 November 2013.
{{cite journal}}: Cite has empty unknown parameter:|1=(help); Cite journal requires|journal=(help) - ^ "Hubble astronomers observe bizarre six-tailed asteroid". Spacetelescope. 7 November 2013.
{{cite news}}: Cite has empty unknown parameter:|1=(help)
See also
- P/2010 A2
- Yarkovsky–O'Keefe–Radzievskii–Paddack effect (aka YORP effect)
External links
- The Extraordinary Multi-Tailed Main-Belt Comet P/2013 P5 (arXiv:1311.1483 : 6 Nov 2013)
- The Multi-Tailed Main-Belt Comet P/2013 P5 (Remanzacco Observatory : 8 Nov 2013)
- Confused Asteroid Sprouts Tails… Six of Them! (Phil Plait : 8 Nov 2013)
- Orbit diagram from JPL Small-Body Database