| 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 | 2.5750AU |
| Perihelion | 2.2643 AU |
| 2.4196 AU | |
| Eccentricity | 0.0642 |
| 3.76yr (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±0.01h[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] | |
1998 Titius, provisional designation1938 DX1, is a metallic–carbonaceousasteroid from the inner regions of theasteroid belt, approximately 14 kilometers in diameter.
It was discovered on 24 February 1938, by German astronomerAlfred Bohrmann atHeidelberg Observatory in southern Germany.[9] On the same night, the body was also observed at the FinnishTurku Observatory.[9] It was later named after astronomerJohann Daniel Titius.[2]
Titius orbits the Sun in theinner main-belt at a distance of 2.3–2.6 AU once every 3 years and 9 months (1,375 days). Its orbit has aneccentricity of 0.06 and aninclination of 8° with respect to theecliptic.[1] It stays in a 2:1orbital resonance with the planetMars.[10]Titius'observation arc starts on the night following its official discovery observation.[9]
According to observations carried out by the JapaneseAkari and NASA'sWide-field Infrared Survey Explorer (WISE) with its subsequentNEOWISE mission,Titius has analbedo between 0.093 and 0.126, and its diameter measures between 14.2 and 16.0 kilometers.[4][5][6] TheCollaborative Asteroid Lightcurve Link assumes a standard albedo of 0.20 and calculates a diameter of 10.8 kilometers with anabsolute magnitude of 12.2.[3]
Itsspectral classification is that of a Xc-type asteroid in theSMASS taxonomy, a transitional spectral type between the two large main groups of metallicX-type and carbonaceousC-type asteroids. Both types are much darker than the stonyS-type asteroids, which are also very common in the inner main-belt.[1][3] In addition,Titius is also classified as aM-type asteroid by WISE.[5]
A rotationallightcurve ofTitius was obtained from photometric observations by American astronomerRobert Stephens at the Californian Santana Observatory in March 2002. Lightcurve analysis gave arotation period of6.13±0.01 hours, during which its brightness amplitude varies by0.30±0.04magnitude (U=3).[7]
Thisminor planet was named after German astronomerJohann Daniel Titius (1729–1796), best known for formulating theTitius-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 craterTitius.[2] The officialnaming citation was published by theMinor Planet Center on 15 October 1977 (M.P.C. 4237).[11]
