1615 Bardwell
| Discovery [1] | |
|---|---|
| Discovered by |
Indiana University (Indiana Asteroid Program) |
| Discovery site | Goethe Link Obs. |
| Discovery date | 28 January 1950 |
| Designations | |
| MPC designation | 1615 Bardwell |
Named after |
Conrad M. Bardwell (astronomer)[2] |
|
1950 BW · 1926 TO 1937 TJ · 1948 RB1 1948 RH1 · 1948 TG | |
| main-belt · Themis [3] | |
| Orbital characteristics [1] | |
| Epoch 31 July 2016 (JD 2457600.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 89.55 yr (32708 days) |
| Aphelion | 3.6822 AU (550.85 Gm) |
| Perihelion | 2.5686 AU (384.26 Gm) |
| 3.1254 AU (467.55 Gm) | |
| Eccentricity | 0.17816 |
| 5.53 yr (2018.1 d) | |
| 99.560° | |
| 0° 10m 42.168s / day | |
| Inclination | 1.6890° |
| 152.54° | |
| 252.18° | |
| Earth MOID | 1.57686 AU (235.895 Gm) |
| Jupiter MOID | 1.72107 AU (257.468 Gm) |
| Jupiter Tisserand parameter | 3.189 |
| Physical characteristics | |
| Dimensions |
27.78 km[4] 31.579±0.250 km[5] 25.01±1.49 km[6] 31±3 km[7] |
Mean radius | 13.89 ± 0.8 km |
| 18 h (0.75 d)[lower-alpha 1][1] | |
|
0.0642[4] 0.0497±0.0192[5] 0.079±0.015[6] 0.05±0.01[7] 0.0642 ± 0.008[1] | |
|
B–V = 0.692 U–B = 0.329 Tholen = B B [3] | |
| 11.38 | |
|
| |
1615 Bardwell, provisional designation 1950 BW, is a rare-type bluish asteroid from the outer region of the asteroid belt, that measures about 30 kilometers in diameter. It was discovered by the Indiana Asteroid Program at the U.S. Goethe Link Observatory near Brooklyn, Indiana at on 28 January 1950.[8]
The dark asteroid is a member of the Themis family, a dynamical family of outer-belt asteroids with nearly coplanar ecliptical orbits. It orbits the Sun at a distance of 2.6–3.7 AU once every five and a half years (2,014 days). Its orbit shows an eccentricity of 0.18 and is tilted by 2 degrees to the plane of the ecliptic. It has a rotation period of 18 hours[lower-alpha 1] and an albedo between 0.05 and 0.08, based on data from the IRAS, WISE and NEOWISE surveys.[4][5][6][7]
It is a B-type asteroid under the Tholen classification taxonomy, a rare subtype of the abundant carbonaceous C-types found in the outer belt. The spectra of B-type bodies show a broad absorption feature at one mircon wavelength that is associated with the presence of magnetite and is what gives the asteroid its blue tint.[9] There are only a few dozens asteroids known to display such a B-spectrum.[10]
The Themistian asteroids was named after Conrad M. Bardwell (1926–2010), a research associate at the Cincinnati Observatory and later associate director of the Minor Planet Center in Cambridge, Massachusetts, United States. Bardwell successfully established numerous identifications from observations in widely separated oppositions and provided observers with reliable data of orbital elements.[2]
References
- 1 2 Tedesco (1979): rotation period of 18 hours with a brightness amplitude of 0.2. Summary figures at Asteroid Lightcurve Database for (1615) Bardwell
- 1 2 3 4 "JPL Small-Body Database Browser: 1615 Bardwell (1950 BW)" (2015-10-11 last obs.). Jet Propulsion Laboratory. Retrieved 25 April 2016.
- 1 2 Schmadel, Lutz D. (2003). Dictionary of Minor Planet Names – (1615) Bardwell. Springer Berlin Heidelberg. p. 128. ISBN 978-3-540-29925-7. Retrieved 15 November 2015.
- 1 2 "LCDB Data for (1615) Bardwell". Asteroid Lightcurve Database (LCDB). Retrieved 15 November 2015.
- 1 2 3 Tedesco, E. F.; Noah, P. V.; Noah, M.; Price, S. D. (October 2004). "IRAS Minor Planet Survey V6.0". NASA Planetary Data System. Bibcode:2004PDSS...12.....T. Retrieved 15 November 2015.
- 1 2 3 Mainzer, A.; Grav, T.; Masiero, J.; Hand, E.; Bauer, J.; et al. (November 2011). "NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results". The Astrophysical Journal. 741 (2): 25. arXiv:1109.6407
. Bibcode:2011ApJ...741...90M. doi:10.1088/0004-637X/741/2/90. Retrieved 15 November 2015. - 1 2 3 Masiero, Joseph R.; Mainzer, A. K.; Grav, T.; Bauer, J. M.; Cutri, R. M.; et al. (November 2012). "Preliminary Analysis of WISE/NEOWISE 3-Band Cryogenic and Post-cryogenic Observations of Main Belt Asteroids". The Astrophysical Journal Letters. 759 (1): 5. arXiv:1209.5794. Bibcode:2012ApJ...759L...8M. doi:10.1088/2041-8205/759/1/L8. Retrieved 15 November 2015.
- 1 2 3 Alí-Lagoa, V.; de León, J.; Licandro, J.; Delbó, M.; Campins, H.; et al. (June 2013). "Physical properties of B-type asteroids from WISE data". Astronomy and Astrophysics. 554: 16. arXiv:1303.5487. Bibcode:2013A&A...554A..71A. doi:10.1051/0004-6361/201220680. Retrieved 1 December 2015.
- ↑ "1615 Bardwell (1950 BW)". Minor Planet Center. Retrieved 15 November 2015.
- ↑ Yang, Bin; Jewitt, David (September 2010), "Identification of Magnetite in B-type Asteroids", The Astronomical Journal, 140 (3), pp. 692–698, arXiv:1006.5110, Bibcode:2010AJ....140..692Y, doi:10.1088/0004-6256/140/3/692
- ↑ "JPL db query spectral type = B (SMASSII and/or Tholen)". JPL Small-Body Database. Jet Propulsion Laboratory. Retrieved 15 November 2015.
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 (1)-(5000) – Minor Planet Center
- 1615 Bardwell at the JPL Small-Body Database
