|Discovered by||Alphonse Borrelly|
|1905 II; 1911 VIII; 1918 IV;|
1925 VIII; 1932 IV; 1953 IV;
1960 V; 1967 VIII; 1974 VII;
1981 IV; 1987 XXXIII; 1994 XXX
|Epoch September 8, 2001 (JD 2452160.5)|
(February 1, 2022)
Comet Borrelly or Borrelly's Comet (official designation: 19P/Borrelly) is a periodic comet, which was visited by the spacecraft Deep Space 1 in 2001. The comet last came to perihelion (closest approach to the Sun) on May 28, 2015. The comet's nucleus, seen in the adjacent image, is particularly notable for being shaped like a bowling pin.
Deep Space 1 flyby
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.
- Seiichi Yoshida (2014-08-10). "19P/Borrelly". Seiichi Yoshida's Comet Catalog. Retrieved 2014-10-29.
- 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 American Astronomical Society. 126 (1): 444–451. Bibcode:2003AJ....126..444W. doi:10.1086/375752. Retrieved 2008-12-16.
- 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.
- 19P – Gary W. Kronk's Cometography
- Elements and Ephemeris for 19P/Borrelly – Minor Planet Center