Comet Borrelly /bɒˈrɛli/ or Borrelly's Comet (official designation: 19P/Borrelly) is a comet with a period of 6.85 years that was visited by the spacecraft Deep Space 1 in 2001. The comet last came to perihelion (closest approach to the Sun) on February 1, 2022[1][8] and will next come to perihelion on December 11, 2028.[2]
 | |
| Discovery | |
|---|---|
| Discovered by | Alphonse Borrelly |
| Discovery date | December 28, 1904 |
| Designations | |
| 1905 II; 1911 VIII; 1918 IV; 1925 VIII; 1932 IV; 1953 IV; 1960 V; 1967 VIII; 1974 VII; 1981 IV; 1987 XXXIII; 1994 XXX | |
| Orbital characteristics | |
| Epoch 2022-08-09 (JD 2459800.5) | |
| Aphelion | 5.90 AU[1] |
| Perihelion | 1.306 AU[1] |
| 3.61 AU | |
| Eccentricity | 0.6377 |
| 6.85 yr | |
| Inclination | 29.30° |
| 2028-Dec-11[2] February 1, 2022 (last)[1] | |
| Earth MOID | 0.36 AU (54 million km) |
| Physical characteristics | |
| Dimensions | 8×4×4 km[3] |
| 2.4 km[4] | |
| Mass | 2×1013 kg[5] |
Mean density | 0.3 g/cm3[6] |
| Albedo | 0.03[7] |
| Perihelion distance at recent epochs[1] | |||||||
| Epoch | Perihelion (AU) | ||||||
|---|---|---|---|---|---|---|---|
| 2028 | 1.310[2] | ||||||
| 2022 | 1.306 | ||||||
| 2015 | 1.349 | ||||||
| 2008 | 1.355 | ||||||
| Date & time of closest approach |
Earth distance (AU) |
Sun distance (AU) |
Velocity wrt Earth (km/s) |
Velocity wrt Sun (km/s) |
Uncertainty region (3-sigma) |
Reference |
|---|---|---|---|---|---|---|
| 2028-Dec-05 19:12 ± 6 min | 0.413 AU (61.8 million km; 38.4 million mi; 161 LD) | 1.31 AU (196 million km; 122 million mi; 510 LD) | 17.3 | 33.3 | ± 41 thousand km | Horizons |
Deep Space 1 returned images of the comet's nucleus from 3400 kilometers away. At 45 meters per pixel, it was the highest resolution view ever seen of a comet.[9]
Discovery
editThe comet was discovered by Alphonse Borrelly during a routine search for comets at Marseilles, France on December 28, 1904.
Exploration
editDeep Space 1 flyby
edit
Deep Space 1 · 9969 Braille · Earth · 19P/Borrelly
On September 21, 2001 the spacecraft Deep Space 1, which was launched to test new equipment in space, performed a flyby of Borrelly. It was steered toward the comet during the extended mission of the craft, and presented an unexpected bonus for the mission scientists. Despite the failure of a system that helped determine its orientation, Deep Space 1 managed to send back to Earth what were, at the time, the best images and other science data from a comet.
References
edit- ^ a b c d e MPC
- ^ a b c "Horizons Batch for 19P/Borrelly (90000304) on 2028-Dec-11" (Perihelion occurs when rdot flips from negative to positive). JPL Horizons. Archived from the original on 2023-02-11. Retrieved 2023-07-06. (JPL#K222/14 Soln.date: 2023-May-25)
- ^ Weaver, H. A.; Stern, S.A.; Parker, J. Wm. (2003). "Hubble Space Telescope STIS Observations of Comet 19P/BORRELLY during the Deep Space 1 Encounter". The Astronomical Journal. 126 (1). The American Astronomical Society: 444–451. Bibcode:2003AJ....126..444W. doi:10.1086/375752.
- ^ "19P/Borrelly: Facts & Figures". Archived from the original on 2014-08-09. Retrieved 2014-08-08.
- ^ Using the volume of an ellipsoid of 8x4x4km * a rubble pile density of 0.3 g/cm3 yields a mass (m=d*v) of 2.0E+13 kg.
- ^ D. T. Britt; G. J. Consol-magno SJ; W. J. Merline (2006). "Small Body Density and Porosity: New Data, New Insights" (PDF). Lunar and Planetary Science XXXVII. Archived (PDF) from the original on 17 December 2008. Retrieved 2008-12-16.
- ^ Robert Roy Britt (2001-11-29). "Comet Borrelly Puzzle: Darkest Object in the Solar System". Space.com. Archived from the original on 22 January 2009. Retrieved 2008-12-16.
- ^ Seiichi Yoshida (2021-04-03). "19P/Borrelly". Seiichi Yoshida's Comet Catalog. Retrieved 2022-06-15.
- ^ Beatty, Kelly (25 June 2004). "Meet Comet Borrelly". Sky & Telescope. Retrieved 27 January 2021.
External links
edit- http://jcometobs.web.fc2.com/pcmtn/0019p.htm
- 19P – Gary W. Kronk's Cometography
- Elements and Ephemeris for 19P/Borrelly – Minor Planet Center