(5496) 1973 NA
Discovery [1] | |
---|---|
Discovered by | E. F. Helin |
Discovery site | Palomar Obs. |
Discovery date | 4 July 1973 |
Designations | |
MPC designation | (5496) 1973 NA |
1973 NA · 1992 OA | |
Apollo · NEO | |
Orbital characteristics [1] | |
Epoch 31 July 2016 (JD 2457600.5) | |
Uncertainty parameter 0 | |
Observation arc | 41.30 yr (15,086 days) |
Aphelion | 3.9838 AU |
Perihelion | 0.8866 AU |
2.4352 AU | |
Eccentricity | 0.6359 |
3.80 yr (1,388 days) | |
137.18° | |
0° 15m 33.84s / day | |
Inclination | 67.993° |
101.06° | |
118.01° | |
Earth MOID | 0.0902 AU |
Physical characteristics | |
Dimensions | 1.88 km (calculated)[2] |
±0.001 2.855h[lower-alpha 1] | |
0.20 (assumed)[2] | |
C/X [3] · S [2] | |
16.0[1][2] | |
|
(5496) 1973 NA, is a very eccentric and heavily tilted asteroid, classified as near-Earth object of the Apollo group, approximately 2 kilometers in diameter. It was discovered on 4 July 1973, by American astronomer Eleanor Helin at the U.S. Palomar Observatory in California.[4] At the time of its discovery, it was the most highly inclined minor planet known to exist.
The asteroid orbits the Sun at a distance of 0.9–4.0 AU once every 3 years and 10 months (1,388 days). Its orbit has a high eccentricity of 0.64 and an exceptionally high inclination of 68° with respect to the ecliptic.[1] No precoveries were taken. The asteroid's observation arc even begins 2 days after its discovery.[4]
The body was also one of the first known near-Earth asteroids. Its discovery happened just two days after it had passed 0.07984 AU (11,900,000 km) from Earth on one of its closest approaches ever computed.[5] It was then tracked for more than a month, but was not seen again until its next close approach in 1992, when it was recovered by the Siding Spring Observatory in Australia.[4] Its minimum orbit intersection distance with Earth is now 0.0902 AU (13,500,000 km).[1]
The stony S-type asteroid is also classified as a transitional C/X-type according to observations by the NASA IRTF telescope.[3] A rotational light-curve for this asteroid was obtained by American astronomer Brian Skiff from photometric observations made in June 2011. The light-curve gave a rotation period of ±0.001 hours with a brightness variation of 0.15 in 2.855magnitude (U=3).[lower-alpha 1] The Collaborative Asteroid Lightcurve Link assumes a standard albedo for stony asteroids of 0.20 and calculates a diameter of 1.88 kilometers, based on an absolute magnitude of 16.0.[2]
The asteroid is expected to be related to the Quadrantids January meteor shower.[6]
References
- 1 2 Skiff (2011) web: rotation period ±0.001 hours with a brightness amplitude of 2.855 mag. Observation rated Quality Code (U) of 3. Summary figures at 0.15Collaborative Asteroid Lightcurve Link (CALL) for (5496) 1973 NA
- 1 2 3 4 5 "JPL Small-Body Database Browser: 5496 (1973 NA)" (2014-10-25 last obs.). Jet Propulsion Laboratory. Retrieved 1 March 2016.
- 1 2 3 4 5 "LCDB Data for (5496)". Asteroid Lightcurve Database (LCDB). Retrieved 24 May 2016.
- 1 2 Thomas, Cristina A.; Emery, Joshua P.; Trilling, David E.; Delbó, Marco; Hora, Joseph L.; Mueller, Michael (January 2014). "Physical characterization of Warm Spitzer-observed near-Earth objects". Icarus. 228: 217–246. arXiv:1310.2000. Bibcode:2014Icar..228..217T. doi:10.1016/j.icarus.2013.10.004. Retrieved 24 May 2016.
- 1 2 3 "5496 (1973 NA)". Minor Planet Center. Retrieved 1 March 2016.
- ↑ "JPL Small-Body Database Browser: 5496 (1973 NA) – Close-Approach Data". Jet Propulsion Laboratory. Retrieved 1 March 2016.
- ↑ Williams, Iwan P.; Collander-Brown, S. J. (February 1998). "The parent of the Quadrantid meteoroid stream". Monthly Notices of the Royal Astronomical Society. 294: 127. Bibcode:1998MNRAS.294..127W. doi:10.1046/j.1365-8711.1998.01168.x. Retrieved 1 March 2016.
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
- Discovery Circumstances: Numbered Minor Planets (5001)-(10000) – Minor Planet Center
- (5496) 1973 NA at the JPL Small-Body Database