1998 Titius, provisional designation 1938 DX1, is a metallic–carbonaceous asteroid from the inner regions of the asteroid belt, approximately 14 kilometers in diameter.
| Discovery[1] | |
|---|---|
| Discovered by | A. Bohrmann |
| Discovery site | Heidelberg Obs. |
| Discovery date | 24 February 1938 |
| Designations | |
| (1998) Titius | |
Named after | Johann Titius (astronomer)[2] |
| 1938 DX1 · 1966 TF | |
| main-belt · (inner) [3] | |
| Orbital characteristics[1] | |
| Epoch 4 September 2017 (JD 2458000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 79.27 yr (28,955 days) |
| Aphelion | 2.5750 AU |
| Perihelion | 2.2643 AU |
| 2.4196 AU | |
| Eccentricity | 0.0642 |
| 3.76 yr (1,375 days) | |
| 335.11° | |
| 0° 15m 42.84s / day | |
| Inclination | 7.6265° |
| 351.78° | |
| 246.70° | |
| Physical characteristics | |
| Dimensions | 10.79 km (calculated)[3] 14.24±0.17 km[4] 14.782±0.081 km[5] 15.98±0.35 km[6] |
| 6.13±0.01 h[7] | |
| 0.093±0.004[6] 0.1066±0.0037[5] 0.126±0.031[4] 0.20 (assumed)[3] | |
| SMASS = Xc[1] M[5] · C[8] · X[3] | |
| 12.10[4] · 12.15±0.22[8] · 12.2[1][3][5][6] | |
It was discovered on 24 February 1938, by German astronomer Alfred Bohrmann at Heidelberg Observatory in southern Germany.[9] On the same night, the body was also observed at the Finnish Turku Observatory.[9] It was later named after astronomer Johann Daniel Titius.[2]
Orbit and classification
editTitius orbits the Sun in the inner main-belt at a distance of 2.3–2.6 AU once every 3 years and 9 months (1,375 days). Its orbit has an eccentricity of 0.06 and an inclination of 8° with respect to the ecliptic.[1] It stays in a 2:1 orbital resonance with the planet Mars.[10] Titius' observation arc starts on the night following its official discovery observation.[9]
Physical characteristics
editDiameter and albedo
editAccording to observations carried out by the Japanese Akari and NASA's Wide-field Infrared Survey Explorer (WISE) with its subsequent NEOWISE mission, Titius has an albedo between 0.093 and 0.126, and its diameter measures between 14.2 and 16.0 kilometers.[4][5][6] The Collaborative Asteroid Lightcurve Link assumes a standard albedo of 0.20 and calculates a diameter of 10.8 kilometers with an absolute magnitude of 12.2.[3]
Spectral type
editIts spectral classification is that of a Xc-type asteroid in the SMASS taxonomy, a transitional spectral type between the two large main groups of metallic X-type and carbonaceous C-type asteroids. Both types are much darker than the stony S-type asteroids, which are also very common in the inner main-belt.[1][3] In addition, Titius is also classified as a M-type asteroid by WISE.[5]
Rotation period
editA rotational lightcurve of Titius was obtained from photometric observations by American astronomer Robert Stephens at the Californian Santana Observatory in March 2002. Lightcurve analysis gave a rotation period of 6.13±0.01 hours, during which its brightness amplitude varies by 0.30±0.04 magnitude (U=3).[7]
Naming
editThis minor planet was named after German astronomer Johann Daniel Titius (1729–1796), best known for formulating the Titius-Bode law, which states that each subsequent planet in the Solar System is roughly twice as far from the Sun than the previous one. He is also honored by the lunar crater Titius.[2] The official naming citation was published by the Minor Planet Center on 15 October 1977 (M.P.C. 4237).[11]
References
edit- ^ a b c d e f "JPL Small-Body Database Browser: 1998 Titius (1938 DX1)" (2017-06-05 last obs.). Jet Propulsion Laboratory. Retrieved 1 July 2017.
- ^ a b c Schmadel, Lutz D. (2007). "(1998) Titius". Dictionary of Minor Planet Names – (1998) Titius. Springer Berlin Heidelberg. p. 162. doi:10.1007/978-3-540-29925-7_1999. ISBN 978-3-540-00238-3.
- ^ a b c d e f g "LCDB Data for (1998) Titius". Asteroid Lightcurve Database (LCDB). Retrieved 8 December 2016.
- ^ a b c d Masiero, Joseph R.; Mainzer, A. K.; Grav, T.; Bauer, J. M.; Cutri, R. M.; Nugent, C.; 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 8 December 2016.
- ^ a b c d e f Mainzer, A.; Grav, T.; Masiero, J.; Hand, E.; Bauer, J.; Tholen, D.; 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.
- ^ a b c d Usui, Fumihiko; Kuroda, Daisuke; Müller, Thomas G.; Hasegawa, Sunao; Ishiguro, Masateru; Ootsubo, Takafumi; et al. (October 2011). "Asteroid Catalog Using Akari: AKARI/IRC Mid-Infrared Asteroid Survey". Publications of the Astronomical Society of Japan. 63 (5): 1117–1138. Bibcode:2011PASJ...63.1117U. doi:10.1093/pasj/63.5.1117. (online, AcuA catalog p. 153)
- ^ a b Stephens, R. D. (September 2002). "Photometry of 973 Aralia, 1189 Terentia, 1040 Klumpkea, and 1998 Titius". The Minor Planet Bulletin. 29: 47–48. Bibcode:2002MPBu...29...47S. Retrieved 8 December 2016.
- ^ a b Veres, Peter; Jedicke, Robert; Fitzsimmons, Alan; Denneau, Larry; Granvik, Mikael; Bolin, Bryce; et al. (November 2015). "Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 - Preliminary results". Icarus. 261: 34–47. arXiv:1506.00762. Bibcode:2015Icar..261...34V. doi:10.1016/j.icarus.2015.08.007. Retrieved 8 December 2016.
- ^ a b c "1998 Titius (1938 DX1)". Minor Planet Center. Retrieved 8 December 2016.
- ^ Gallardo, Tabaré; Venturini, Julia; Roig, Fernando; Gil-Hutton, Ricardo (August 2011). "Origin and sustainability of the population of asteroids captured in the exterior resonance 1:2 with Mars". Icarus. 214 (2): 632–644. arXiv:1105.5108. Bibcode:2011Icar..214..632G. doi:10.1016/j.icarus.2011.05.029. Retrieved 15 December 2015.
- ^ Schmadel, Lutz D. (2009). "Appendix – Publication Dates of the MPCs". Dictionary of Minor Planet Names – Addendum to Fifth Edition (2006–2008). Springer Berlin Heidelberg. p. 221. doi:10.1007/978-3-642-01965-4. ISBN 978-3-642-01964-7.
External links
edit- 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 (1)-(5000) – Minor Planet Center
- 1998 Titius at AstDyS-2, Asteroids—Dynamic Site
- 1998 Titius at the JPL Small-Body Database
