# 17246 Christophedumas

(Redirected from (17246) 2000 GL74)
Discovery [1] Orbit of 17246 Christophedumas LINEAR Lincoln Lab ETS 5 April 2000 2000 GL74 · 1973 VM main-belt · Koronis [2] Epoch 13 January 2016 (JD 2457400.5) Uncertainty parameter 0 16138 days (44.18 yr) 2.9016 AU (434.07 Gm) 2.7788 AU (415.70 Gm) 2.8402 AU (424.89 Gm) 0.021625 4.79 yr (1748.3 d) 57.137° 0° 12m 21.276s / day 2.4445° 34.453° 229.70° 1[a][3] 4.5 km[4] 5.04 km (calculated)[2] 10 h (0.42 d)[5] 0.21[3] S [2][4] 13.8[1][4]

17246 Christophedumas, provisional designation 2000 GL74, is a binary[a] asteroid from the main-belt and member of the Koronis family, about 5 kilometers in diameter.[2] It was discovered on 5 April 2000, by the Lincoln Near-Earth Asteroid Research (LINEAR) program at Lincoln Laboratory's Experimental Test Site near Socorro, New Mexico.[6] It is known to possess an asteroid moon, designated S/2004 (17246) 1. The S-type asteroid orbits the Sun at a distance of 2.8–2.9 AU once every 4 years and 9 months (1,748 days) and shows an eccentricity of 0.02 and an inclination of 2 degrees from the plane of the ecliptic.[1]

## Characteristics

17246 Christophedumas is more reflective than most asteroids, with an albedo of 0.21. Even so, it is not very large, having a size of only 4.5 kilometres.[4] Its rotation period of 10 hours is not unusual, however.[5]

### Close approaches

3 Juno, the asteroid that 17246 Christophedumas will approach on January 9, 2129

On January 9, 2129, the asteroid will come within 3,639,998 kilometers of 3 Juno, one of the largest asteroids in the main-belt, and will pass it with a relative velocity of 6.597 km/s.[1]

## Moon

17246 Christophedumas has one moon, S/2004 (17246) 1. It is 44% the size of its primary, at 2 km.[4] While its rotation period and orbital eccentricity is not yet known, it is known that the moon completes one orbit every 90 days at a distance of about 250 km. From the surface of 17246 Christophedumas, S/2004 (17246) 1 would have an apparent diameter of about 0.668°, slightly larger than the Moon appears from Earth.[b]

## Notes

1. ^ a b IAUC 8293, S/2004 (17246) 1: reports the discovery on Jan. 14.9 UT, on six direct images (two sets of three images taken 20 min apart in time) made with the Hubble Space Telescope (+ ACS/HRC), of a satellite of minor planet (17246) 2000 GL_74 (V about 18.5). The satellite is clearly separated from the primary in five images. On Jan. 14.9195, the satellite was at separation 0".16 (projected separation 230 km) in p.a. 280 deg. Using the average albedo of the Koronis family (about 0.21), to which (17246) belongs, the size of the primary is estimated to be 4.5 km. The brightness difference is about 2 mag, giving an estimated diameter of the secondary of about 2 km.
Reported by: P. M. Tamblyn, Southwest Research Institute (SwRI) and Binary Astronomy; W. J. Merline, C. R. Chapman, D. Nesvorny, and D. D. Durda, SwRI; C. Dumas, Jet Propulsion Laboratory; A. D. Storrs, Towson University; L. M. Close, University of Arizona; and F. Menard, Observatoire de Grenoble
2. ^ Calculated by solving ${\displaystyle \scriptstyle {\mathrm {tan} \left({\frac {\theta }{2}}\right)={\frac {\mathrm {radius~of~moon} }{\mathrm {distance~from~surface~of~asteroid~to~center~of~moon} }}}}$.

## References

1. "JPL Small-Body Database Browser: 17246 Christophedumas (2000 GL74)" (2015-06-22 last obs.). Jet Propulsion Laboratory. Retrieved 5 April 2016.
2. ^ a b c d "LCDB Data for (17246)". Asteroid Lightcurve Database (LCDB). Retrieved February 2016.
3. ^ a b Tamblyn, P. M.; Merline, W. J.; Chapman, C. R.; Nesvorny, D.; Durda, D. D.; Dumas, C.; et al. (February 2004). "S/2004 (17246) 1". IAU Circular (8293). Bibcode:2004IAUC.8293....3T.
4. Johnston, W. R. (1 September 2005). "(17246) 2000 GL74". Johnston's Archive. Retrieved 2013-09-24.
5. ^ a b Polishook, D.; Brosch, N.; Prialnik, D. (March 2011). "Rotation periods of binary asteroids with large separations - Confronting the Escaping Ejecta Binaries model with observations". Icarus 212 (1): 167–174. arXiv:1012.4810. Bibcode:2011Icar..212..167P. doi:10.1016/j.icarus.2010.12.020.
6. ^ "17246 Christophedumas". Minor Planet Center. Retrieved February 2016.