| 161989 Cacus (1978 CA) |
| Classification: Apollo [NEO, PHA] SPK-ID: 2161989 |
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Orbital Elements at Epoch 2459200.5 (2020-Dec-17.0) TDB
Reference: JPL 180 (heliocentric ecliptic J2000)
| Element | Value | Uncertainty (1-sigma) | Units |
| e | .2139591156145607 | 1.988e-08 | |
| a | 1.123168985782361 | 7.9316e-10 | au |
| q | .8828567428986642 | 2.1972e-08 | au |
| i | 26.06088239836219 | 1.0666e-06 | deg |
| node | 161.2296146692731 | 1.6528e-06 | deg |
| peri | 102.1921603183097 | 2.3107e-06 | deg |
| M | 259.0497008914565 | 2.8995e-06 | deg |
| tp | 2459322.418943402761
(2021-Apr-17.91894340) | 3.5949e-06 | TDB |
| period | 434.7765188669906
1.19 | 4.6055e-07
1.261e-09 | d
yr |
| n | .8280115976321466 | 8.7709e-10 | deg/d |
| Q | 1.363481228666058 | 9.6286e-10 | au |
|
| | Orbit Determination Parameters
Additional Information
|
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Physical Parameter Table
| Parameter |
Symbol |
Value |
Units |
Sigma |
Reference |
Notes |
| absolute magnitude |
H |
17.2 |
|
n/a |
MPO366964 |
|
| diameter |
diameter |
1.9 |
km |
n/a |
Hazards due to Comets and Asteroids (1994), Ed. T. Gehrels, pp.540-543 |
|
| rotation period |
rot_per |
3.7538 |
h |
n/a |
LCDB (Rev. 2020-October); Warner et al., 2009 |
Published Reference List:
[Degewij, J. (1978) Messenger 13, 5; IAUC 3193.]
[Schuster, H.E.; Surdej, A.; Surdej, J. (1979) Astron. Astrophys. Suppl. Ser. 37, 483-486.]
[Pravec, P.; Wolf, M.; Sarounova, L. (2003) http://www.asu.cas.cz/~ppravec/neo.htm]
[Koehn, B.W.; Bowell, E.L.G.; Skiff, B.A.; Sanborn, J.J.; et al. (2014) Minor Planet Bull. 41, 286-300.]
[Durech, J.; Vokrouhlicky, D.; Pravec, P.; Hanus, J.; et al. (2018) Astron. Astrophys. 609, A86.]
[Skiff, B.A.; McLelland, K.P.; Sanborn, J.; Pravec, P.; Koehn, B.W. (2019). Minor Planet Bull. 46, 458-503.] |
| geometric albedo |
albedo |
0.09 |
|
n/a |
Hazards due to Comets and Asteroids (1994), Ed. T. Gehrels, pp.540-543 |
|
| B-V |
BV |
0.910 |
|
0.017 |
EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 |
#obs=3; phase (min.=8.42, mean=14.40, max.=26.34) deg. |
| U-B |
UB |
0.484 |
|
0.020 |
EAR-A-5-DDR-UBV-MEAN-VALUES-V1.2 |
#obs=3; phase (min.=8.42, mean=14.40, max.=26.34) deg. |
| Tholen spectral type |
spec_T |
S |
|
n/a |
EAR-A-5-DDR-TAXONOMY-V4.0 |
used 2 color indices |
|
| 161989 Cacus | Discovered 1978 Feb. 8 by H.-E. Schuster at the European Southern Observatory. |
| The fire-breathing monster Cacus, son of Vulcan, stole cattle Hercules had acquired as his tenth labor. Although Cacus tried to make it appear that the cattle had gone in the opposite direction, Hercules found them and strangled Cacus, erecting an altar at the spot that later became the Forum Boarium, the Rome cattle market. |
| NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character) |
| Reference: 20071124/MPCPages.arc | Last Updated: 2007-11-26 |
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