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Artist's impression of 8405 Asbolus
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Discovery
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| Discovered by | J. V. Scotti and R. Jedicke |
| Discovery date | April 5, 1995 |
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Designations
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| Named after | Asbolus |
| Alternate name(s) | 1995 GO |
| Minor planet category |
centaur |
| Epoch November 30, 2008 (JD 2454800.5) | |
| Aphelion | 29.31 AU |
| Perihelion | 6.843 AU |
| Semi-major axis | 18.07 AU |
| Eccentricity | 0.6214 |
| Orbital period | 76.88 yr |
| Mean anomaly | 29.6 |
| Inclination | 17.61 |
| Longitude of ascending node | 6.0 |
| Argument of perihelion | 290.4 |
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Physical characteristics
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| Dimensions | 84 ± 8 km (Spitzer)[2] 76 km (Johnston)[3] |
| Rotation period | 8.87 hr[1] |
| Albedo | 0.05[2] 0.12±0.03[4] |
| Apparent magnitude | ~21.1[5] |
| Absolute magnitude (H) | 9.0[1] |
8405 Asbolus ( /ˈæzbɵləs/; from Greek: Άσβολος) is a centaur orbiting between the orbits of Jupiter and Neptune. It was discovered by James V. Scotti and Robert Jedicke of Spacewatch at Kitt Peak Observatory on April 5, 1995. It is named after Asbolus (Greek for sooty), a centaur in Greek mythology. Its provisional designation was 1995 GO.
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Observations with the Spitzer Space Telescope in 2007 resulted in a diameter calculation of about 84 ± 8 km.[2]
No resolved images of it have ever been made but, in 1998, spectral analysis of its composition by the Hubble Space Telescope revealed a fresh impact crater on its surface, less than 10 million years old.[6] Centaurs are dark in colour, because their icy surfaces have darkened after long exposure to solar radiation and the solar wind. However, fresh craters excavate more reflective ice from below the surface, and that is what Hubble has detected on Asbolus.
Centaurs have short dynamical lifetimes due to perturbations by the giant planets. Asbolus is estimated to have an orbital half-life of about 860 kiloannum.[7] Asbolus is currently classified as a SN centaur since Saturn is considered to control the perihelion and Neptune controls the aphelion.[7] Asbolus currently has a perihelion (q) of 6.8AU,[1] so is also influenced by Jupiter. Centaurs with a perihelion less than 6.6AU are very strongly influenced by Jupiter and for classification purposes are considered to have a perihelion under the control of Jupiter.[7] In about ten thousand years, clones of the orbit of Asbolus suggest that its perihelion classification may come under the control of Jupiter.[8]
Predicting the overall orbit and position of Asbolus beyond a few thousand years is difficult because of errors in the known trajectory, error amplification by perturbations due to all of the gas giants, and the possibility of perturbation as a result of cometary outgassing/fragmentation. Compared to centaur Nessus, the orbit of Asbolus is currently much more chaotic.
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