50000 Quaoar
50000 Quaoar (symbol: .svg){kind=small}
) is a Trans-Neptunian object and is also a dwarf planet. It was discovered on June 4, 2002 by Chad Trujillo and Michael Brown at the California Institute of Technology.
 Quaoar and its moon Weywot, imaged by the Hubble Space Telescope | |
| Discovery[1] | |
|---|---|
| Discovered by | Chad Trujillo, Michael Brown |
| Discovery date | 2002 Jun 05 10:48:08 PDT on an image taken 2002 June 04 05:41:40 UT |
| Designations | |
| 2002 LM60 | |
| Cubewano Dwarf planet KBO Plutoid TNO[2][3] | |
| Orbital characteristics[4] | |
| Epoch May 18, 2008 (JD 2 454 600.5) | |
| Aphelion | 6.716 275 Tm (45.286 AU) |
| Perihelion | 6.270 316 Tm (41.928 AU) |
| 6.493 296 Tm (43.607 AU) | |
| Eccentricity | 0.038 4 |
| 105 181.6 d (287.97 a) | |
Average orbital speed | 4.52 km/s |
| 284.861° | |
| Inclination | 7.988° |
| 188.893° | |
| 148.508° | |
| Physical characteristics | |
| Dimensions | 1260 ± 190 km (direct)[5] 844+207−190 km (thermal)[6] |
| Mass | (1.0–2.6)×1021 kg |
Mean density | 2.0? g/cm³ |
Equatorial surface gravity | 0.276–0.376 m/s² |
Equatorial escape velocity | 0.523–0.712 km/s |
| 0.088 +0.021−0.012 [5] 0.198 6 +0.13−0.07 [6] | |
| Temperature | ~43 K |
| (moderately red) B-V=0.94, V-R=0.65 | |
| 2.6 | |
.svg){kind=small}
Quaoar has one known moon, named Weywot. It also has a ring. Unexpectedly, the ring is at twice the distance of the Roche limit, which was thought to be the maximum distance of a ring: beyond the Roche limit, the particles in a ring should clump together and form a moon; yet this has not happened to Quaoar's ring. It is thought that the particles do not clump together because of tides created by Weywot. There may also be small shepherd moons on either side of the ring, as there are at Saturn's F Ring.
50000 Quaoar Media
Quaoar was discovered using the Samuel Oschin telescope at Palomar Observatory
Animation of three discovery images taken over a period of 4.5 hours, showing the slow movement of Quaoar (indicated by the arrow)
Ecliptic view of Quaoar's orbit (blue) compared to Pluto (red) and Neptune (white). The approximate perihelion (q) and aphelion (Q) dates are marked for their respective orbits.
Polar view of Quaoar's orbit (yellow) along with various other large Kuiper belt objects
Diagram showing three mutually orthogonal views of Quaoar's ellipsoidal shape
Artist's impression of Quaoar with its ring and its moon Weywot
Light curve graph of a star's brightness as seen by the Gemini North Observatory during the 9 August 2022 occultation by Quaoar and its two rings. The asymmetry of the outer Q1R ring's opacity is apparent from its differing brightness dips before and after the occultation by Quaoar at the center.
References
- ↑ "Frequently Asked Questions About Quaoar". Archived from the original on 2010-01-17. Retrieved 2009-02-19.
{{cite web}}: CS1 maint: bot: original URL status unknown (link) - ↑ Buie, Marc W. (2006-05-17). "Orbit Fit and Astrometric record for 50000". SwRI (Space Science Department). Retrieved 2008-09-19.
- ↑ Marsden, Brian G. (2008-07-17). "MPEC 2008-O05 : Distant Minor Planets (2008 Aug. 2.0 TT)". IAU Minor Planet Center. Harvard-Smithsonian Center for Astrophysics. Archived from the original on 2012-04-09. Retrieved 2008-10-01.
- ↑ "Asteroid Data Services by Lowell Observatory". Archived from the original on 2007-06-21. Retrieved 2020-09-14.
{{cite web}}: CS1 maint: bot: original URL status unknown (link) - ↑ 5.0 5.1 Brown, Michael E. and Chadwick A. Trujillo (2004). "Direct Measurement of the Size of the Large Kuiper Belt Object (50000) Quaoar". The Astronomical Journal. 127 (7018): 2413–2417. doi:10.1086/382513. S2CID 1877283. Archived from the original on 2022-05-17. Retrieved 2022-02-22. Reprint on Brown's site (pdf)
- ↑ 6.0 6.1 Stansberry J., Grundy W., Brown M, Cruikshank D., Spencer J., Trilling D., Margot J-L Physical Properties of Kuiper Belt and Centaur Objects: Constraints from Spitzer Space Telescope To Appear in: Kuiper Belt (M.A. Barucci et al., Eds.) U. Arizona Press, 2007 Preprint
Other websites
- Quaoar discoverers' webpageArchived 2010-08-08 at the Wayback Machine
- Orbital simulation from JPL (Java) /Ephemeris
