Astronomy:7336 Saunders
| Discovery [1] | |
|---|---|
| Discovered by | E. F. Helin |
| Discovery site | Palomar Obs. |
| Discovery date | 6 September 1989 |
| Designations | |
| (7336) Saunders | |
| Named after | R. Stephen Saunders (JPL scientist)[2] |
| 1989 RS1 | |
| Minor planet category | NEO · Amor [1][3] |
| Orbital characteristics [1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 34.63 yr (12,647 days) |
| |{{{apsis}}}|helion}} | 3.4148 AU |
| |{{{apsis}}}|helion}} | 1.1956 AU |
| 2.3052 AU | |
| Eccentricity | 0.4813 |
| Orbital period | 3.50 yr (1,278 days) |
| Mean anomaly | 353.72° |
| Mean motion | 0° 16m 53.76s / day |
| Inclination | 7.1958° |
| Longitude of ascending node | 174.49° |
| 181.51° | |
| Earth MOID | 0.1908 AU · 74.3 LD |
| Physical characteristics | |
| Dimensions | 0.467 km (derived)[4] |
| Rotation period | 6 h[5] 6.423±0.004 h[lower-alpha 1] |
| Geometric albedo | 0.20 (assumed)[4] |
| SMASS = Sq [1] · S [4] | |
| Absolute magnitude (H) | 18.0[5] · 18.45±0.2 (R)[lower-alpha 1] · 18.8[1] · 19.02±0.112[4][6] |
7336 Saunders, provisional designation 1989 RS1, is a stony asteroid and near-Earth object of the Amor group, approximately 0.5 kilometers in diameter.
The asteroid was discovered on 6 September 1989, by American astronomer Eleanor Helin at Palomar Observatory in California, United States.[3] It was named for JPL-project scientist R. Stephen Saunders.[2]
Orbit and classification
Saunders orbits the Sun at a distance of 1.2–3.4 AU once every 3 years and 6 months (1,278 days). Its orbit has an eccentricity of 0.48 and an inclination of 7° with respect to the ecliptic.[1]
A first precovery was taken at the Australian Siding Spring Observatory in 1982, extending the body's observation arc by 7 years prior to its official discovery at Palomar.[3] It has a minimum orbital intersection distance with Earth of 0.1908 AU (28,500,000 km), which corresponds to 74.3 lunar distances.[4]
Physical characteristics
In the SMASS classification, Saunders is a Sq-type, which transitions from the common S-type to the Q-type asteroids.[1] The Collaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and derives a diameter of 467 meters, based on an absolute magnitude of 19.02.[4]
Lightcurve
In October 1989, the first photometric observations of Saunders were made with the ESO 1-metre telescope at La Silla in Chile.[5] It gave a rotation period of 6 hours with a brightness variation of 0.3 magnitude ({{{1}}}). Another rotational lightcurve was obtained by Czech astronomer Petr Pravec at Ondřejov Observatory in August 2003, giving a period of 6.423±0.004 and an amplitude of 0.2 magnitude ({{{1}}}).[lower-alpha 1]
Naming
This minor planet was named in honor of JPL-project scientist R. Stephen Saunders (born 1940), director of the RPIF and head scientist of the Solar System Exploration Office. He worked on the Mars Surveyor 2001/03 program and on the Magellan spacecraft, that visited and mapped Venus in 1990.[2] The official naming citation was published by the Minor Planet Center on 26 July 2000 (M.P.C. 41028).[7]
Notes
- ↑ 1.0 1.1 1.2 Pravec (2003): rotation period 6.423±0.004 hours with a brightness amplitude of 0.2 mag. Summary figures for (7336) Saunders at Collaborative Asteroid Lightcurve Link (CALL) and Pravec, P.; Wolf, M.; Sarounova, L. (2003)
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 "JPL Small-Body Database Browser: 7336 Saunders (1989 RS1)". Jet Propulsion Laboratory. https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2007336.
- ↑ 2.0 2.1 2.2 Schmadel, Lutz D. (2007). "(7336) Saunders". Dictionary of Minor Planet Names – (7336) Saunders. Springer Berlin Heidelberg. p. 591. doi:10.1007/978-3-540-29925-7_6435. ISBN 978-3-540-00238-3.
- ↑ 3.0 3.1 3.2 "7336 Saunders (1989 RS1)". Minor Planet Center. https://www.minorplanetcenter.net/db_search/show_object?object_id=7336.
- ↑ 4.0 4.1 4.2 4.3 4.4 4.5 "LCDB Data for (7336) Saunders". Asteroid Lightcurve Database (LCDB). http://www.minorplanet.info/PHP/generateOneAsteroidInfo.php?AstInfo=7336%7CSaunders.
- ↑ 5.0 5.1 5.2 Hoffmann, Martin; Rebhan, Helge; Neukum, Gerhard; Geyer, Edward H. (January 1993). "Photometric observations of four near-earth asteroids". Acta Astronomica 43: 61–67. ISSN 0001-5237. Bibcode: 1993AcA....43...61H. http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=1993AcA....43...61H. Retrieved 26 September 2016.
- ↑ Pravec, Petr; Harris, Alan W.; Kusnirák, Peter; Galád, Adrián; Hornoch, Kamil (September 2012). "Absolute magnitudes of asteroids and a revision of asteroid albedo estimates from WISE thermal observations". Icarus 221 (1): 365–387. doi:10.1016/j.icarus.2012.07.026. Bibcode: 2012Icar..221..365P. http://adsabs.harvard.edu/cgi-bin/bib_query?bibcode=2012Icar..221..365P. Retrieved 26 September 2016.
- ↑ "MPC/MPO/MPS Archive". Minor Planet Center. https://www.minorplanetcenter.net/iau/ECS/MPCArchive/MPCArchive_TBL.html.
External links
- Asteroid Lightcurve Database (LCDB), query form (info )
- Dictionary of Minor Planet Names, Google books
- Asteroids and comets rotation curves, CdR – Observatoire de Genève, Raoul Behrend
- 7336 Saunders at NeoDyS-2, Near Earth Objects—Dynamic Site
- Ephemeris · Obs prediction · Orbital info · MOID · Proper elements · Obs info · Close · Physical info · NEOCC
- 7336 Saunders at ESA–space situational awareness
- 7336 Saunders at the JPL Small-Body Database
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