astro.wikisort.org - Asteroid

(88710) 2001 SL₉ is a sub-kilometer asteroid and binary system, classified as near-Earth object of Apollo group[1] discovered by NEAT at Palomar Observatory on 18 September 2001. It measures approximately 960 meters in diameter, while its 2001-discovered minor-planet moon has an estimated diameter of 200 meters based on a secondary to primary mean-diameter ration of 0.28.[2]

(88710) 2001 SL₉

Orbit of 2001 SL9
Discovery[1][2]
Discovered by	NEAT
Discovery site	Palomar Obs.
Discovery date	18 September 2001
Designations
Alternative designations	2001 SL9
Orbital characteristics[1]
Epoch 13 January 2016 (JD 2457400.5)
Uncertainty parameter 0
Observation arc	22318 days (61.10 yr)
Aphelion	1.3480 AU (201.66 Gm)
Perihelion	0.77471 AU (115.895 Gm)
Semi-major axis	1.0613 AU (158.77 Gm)
Eccentricity	0.27006
Orbital period (sidereal)	1.09 yr (399.37 d)
Mean anomaly	239.06°
Mean motion	0° 54m 5.112s / day
Inclination	21.900°
Longitude of ascending node	202.86°
Argument of perihelion	329.30°
Known satellites	1
Earth MOID	0.197987 AU (29.6184 Gm)
Jupiter MOID	3.64009 AU (544.550 Gm)
Physical characteristics
Mean diameter	1 km (0.62 mi)[3]
Mass	109 mt
Mean density	1.8 g/cm3[2]
Equatorial surface gravity	0.02565 mm/s2[4]
Equatorial escape velocity	0.05116 mm/s[4]
Synodic rotation period	2.4004 h (0.10002 d)
Sidereal rotation period	2.40035±0.00005 hours[1][5]
Geometric albedo	0.16[2]
Temperature	230-303 K (-43-30°C)[4]
Absolute magnitude (H)	17.6[1]

Near-Earth asteroid

Although 2001 SL₉ is classified as a near-Earth object, it does not pose any threats. It has never, nor will it ever in the next century, come closer than 15,000,000 km (0.1 AU) from Earth or Venus.[1] However, the asteroid would make a good target for a spacecraft flyby, as a flyby to 2001 SL₉ would only require a delta-v of 5.4 km/s.[6]

Moon

2001 SL₉ has one minor-planet moon, S/2001 (88710) 1. It was discovered from lightcurve observations[6] made by Czech astronomer Petr Pravec and collaborators.[2] This moon is approximately 200 m (660 ft) in diameter. Its semi-major axis is 1.6 km (0.99 mi) and its orbital period is 16.4 hours.[2]

References

External links

• Lightcurve plot of (88710) 2001 SL9, Palmer Divide Observatory, B. D. Warner (2001)
• Asteroids with Satellites, Robert Johnston, johnstonsarchive.net
• Asteroid Lightcurve Database (LCDB), query form (info Archived 16 December 2017 at the Wayback Machine)
• Dictionary of Minor Planet Names, Google books
• Asteroids and comets rotation curves, CdR – Observatoire de Genève, Raoul Behrend
• Discovery Circumstances: Numbered Minor Planets (85001)-(90000) – Minor Planet Center
• (88710) 2001 SL9 at NeoDyS-2, Near Earth Objects—Dynamic Site
  • Ephemeris · Obs prediction · Orbital info · MOID · Proper elements · Obs info · Close · Physical info · NEOCC
• (88710) 2001 SL9 at ESA–space situational awareness
  • Ephemerides · Observations · Orbit · Physical Properties · Summary
• (88710) 2001 SL9 at the JPL Small-Body Database
  • Close approach · Discovery · Ephemeris · Orbit diagram · Orbital elements · Physical parameters

---