225 Henrietta
| Discovery | |
|---|---|
| Discovered by | Johann Palisa |
| Discovery date | 19 April 1882 |
| Designations | |
| n/a | |
| Main belt (Cybele) | |
| Orbital characteristics[1] | |
| Epoch 31 July 2016 (JD 2457600.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 120.87 yr (44148 d) |
| Aphelion | 4.28364 AU (640.823 Gm) |
| Perihelion | 2.4945 AU (373.17 Gm) |
| 3.38907 AU (506.998 Gm) | |
| Eccentricity | 0.26396 |
| 6.24 yr (2278.9 d) | |
Average orbital speed | 16.2 km/s |
| 159.155° | |
| 0° 9m 28.703s / day | |
| Inclination | 20.872° |
| 197.113° | |
| 104.149° | |
| Earth MOID | 1.57755 AU (235.998 Gm) |
| Jupiter MOID | 1.70696 AU (255.358 Gm) |
| Jupiter Tisserand parameter | 2.990 |
| Physical characteristics | |
| Dimensions | 120.49±2.5 km |
| 7.3556 h (0.30648 d) | |
| 0.0396±0.002 | |
| C | |
| 8.72 | |
|
| |
225 Henrietta is a very large outer main-belt asteroid. It was discovered by Johann Palisa on April 19, 1882, in Vienna and named after Henrietta, wife of astronomer Pierre J. C. Janssen.
This is classified as a C-type asteroid and is probably composed of privitive carbonaceous material. It has very dark surface, with an albedo of 0.040. Photometric measurements made from the Oakley Southern Sky Observatory during 2012 gave a light curve with a period of 7.352 ± 0.003 hours and a variation in brightness of 0.18 ± 0.02 in magnitude. This is consistent with a synodic rotation period of 7.356 ± 0.001 hours determined in 2000.[2]
In 2001, the asteroid was detected by radar from the Arecibo Observatory at a distance of 1.58 AU. The resulting data yielded an effective diameter of 128 ± 16 km.[3]
225 Henrietta belongs to Cybele group of asteroids and is probably in a 4:7 orbital resonance with the planet Jupiter.
References
- ↑ "225 Henrietta". JPL Small-Body Database. NASA/Jet Propulsion Laboratory. Retrieved 12 May 2016.
- ↑ Moravec, Patricia; Cochren, Joseph; Gerhardt, Michael; et al. (October 2012), "Asteroid Lightcurve Analysis at the Oakley Southern Sky Observatory: 2012 January-April", The Minor Planet Bulletin, 39 (4): 213–216, Bibcode:2012MPBu...39..213M.
- ↑ Magri, Christopher; et al. (January 2007), "A radar survey of main-belt asteroids: Arecibo observations of 55 objects during 1999 2003" (PDF), Icarus, 186 (1): 126–151, Bibcode:2007Icar..186..126M, doi:10.1016/j.icarus.2006.08.018, retrieved 2015-04-14.
External links
- The Asteroid Orbital Elements Database
- Minor Planet Discovery Circumstances
- Asteroid Lightcurve Data File
- 225 Henrietta at the JPL Small-Body Database
