Astronomy:405 Thia
| Discovery | |
|---|---|
| Discovered by | Auguste Charlois |
| Discovery date | 23 July 1895 |
| Designations | |
| (405) Thia | |
| Pronunciation | /ˈθaɪə/[1] |
| Named after | Theia |
| 1895 BZ | |
| Minor planet category | Main belt |
| Orbital characteristics[2] | |
| Epoch 2023-Feb-25 (JD 2460000.5) | |
| Uncertainty parameter 0 | |
| Observation arc | 123.54 years |
| |{{{apsis}}}|helion}} | 3.2145 astronomical unit|AU (480.88 Gm) |
| |{{{apsis}}}|helion}} | 1.9592 AU (293.09 Gm) |
| 2.5861 AU (386.88 Gm) | |
| Eccentricity | 0.24341 |
| Orbital period | 4.16 yr (1518.3 d) |
| Mean anomaly | 336.81° |
| Mean motion | 0° 14m 13.164s / day |
| Inclination | 11.937° |
| Longitude of ascending node | 255.19° |
| |{{{apsis}}}|helion}} | 2 June 2023[2] |
| 308.65° | |
| Earth MOID | 0.975 AU (145.9 million km; 379 LD) |
| Physical characteristics | |
| Dimensions | 124.90±2.3 km[2] 122.14 ± 7.69 km[3] |
| Mass | (1.38 ± 0.14) × 1018 kg[3] |
| Mean density | 1.44 ± 0.30 g/cm3[3] |
| Rotation period | 10.08 h (0.420 d) |
| Geometric albedo | 0.0468±0.002 |
| C[2] | |
| Absolute magnitude (H) | 8.65 |
Thia (minor planet designation: 405 Thia) is a very large main-belt asteroid. It is classified as a C-type asteroid and is probably composed of carbonaceous material. This object was discovered by Auguste Charlois on July 23, 1895, in Nice, and was named after Theia (sometimes written Thea or Thia), a Titaness in Greek mythology.[4]
In 2002, the asteroid was detected by radar from the Arecibo Observatory at a distance of 1.31 AU. The resulting data yielded an effective diameter of 125 ± 16 km.[5] NEOWISE data suggests the asteroid is 110 km in diameter.[2]
On 4 May 1990 Thia passed 0.969 AU (145.0 million km; 377 LD) from Earth[6] and will pass that close again on 29 April 2073.
405 Thia currently has a Minimum orbit intersection distance with Earth of 0.975 AU (145.9 million km; 379 LD)[2] and on 20 March 2023 will be 1.057 astronomical unit|AU (158.1 million km; 411 LD) from Earth. Then on 2 June 2023 the asteroid will reach perihelion (closest approach to the Sun).[2]
| Date & time of closest approach |
Earth distance (AU) |
Sun distance (AU) |
Velocity wrt Earth (km/s) |
Velocity wrt Sun (km/s) |
Uncertainty region (3-sigma) |
Reference |
|---|---|---|---|---|---|---|
| 2023-03-20 19:40 | 1.057 astronomical unit|AU (158.1 million km; 411 LD) | 2.006 AU (300.1 million km; 781 LD) | 6.8 | 23.3 | ± 16 km | Horizons |
References
- ↑ Noah Webster (1884) A Practical Dictionary of the English Language
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 "JPL SBDB: 405 Thia (1895 BZ)". JPL Small-Body Database. NASA/Jet Propulsion Laboratory. https://ssd.jpl.nasa.gov/tools/sbdb_lookup.html#/?sstr=405&view=OPC.
- ↑ 3.0 3.1 3.2 Carry, B. (December 2012), "Density of asteroids", Planetary and Space Science 73: pp. 98–118, doi:10.1016/j.pss.2012.03.009, Bibcode: 2012P&SS...73...98C. See Table 1.
- ↑ Schmadel, Lutz D. (2003). Dictionary of Minor Planet Names. Berlin, Heidelberg, New York: Springer. p. 48. ISBN 3-540-00238-3. https://www.scribd.com/doc/5570999/Dictionary-of-Minor-Planet-Names.
- ↑ Magri, Christopher et al. (January 2007), "A radar survey of main-belt asteroids: Arecibo observations of 55 objects during 1999 2003", Icarus 186 (1): 126–151, doi:10.1016/j.icarus.2006.08.018, Bibcode: 2007Icar..186..126M, http://echo.jpl.nasa.gov/asteroids/MBAs/magri.etal.2007.mbas.pdf, retrieved 2015-04-14.
- ↑ "Horizons Batch for Thia in May 1990". JPL Horizons. https://ssd.jpl.nasa.gov/horizons_batch.cgi?batch=1&COMMAND=%27405%27&START_TIME=%271990-05-04%27&STOP_TIME=%271990-05-05%27&STEP_SIZE=%271%20hour%27&QUANTITIES=%2720%27. Retrieved 2023-02-20.
External links
- 405 Thia at AstDyS-2, Asteroids—Dynamic Site
- 405 Thia at the JPL Small-Body Database
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