2008 ST291

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2008 ST291
Discovery[1]
Discovered by M. E. Schwamb
M. E. Brown
D. L. Rabinowitz
Discovery date September 24, 2008
Designations
MPC designation 2008 ST291
TNO (SDO)[2][3]
Orbital characteristics[4]
Epoch December 9, 2014
Aphelion 154.8±1.7 AU
Perihelion 42.50±0.17 AU
98.6±1.1 AU
Eccentricity 0.5691±0.0064
979±16 yr
22.28±0.41° (M)
Inclination 20.8248±0.0032°
331.1557±0.0070°
324.62±0.19°
Physical characteristics
Dimensions 370–820 km[4][5]
612 km[6][7]
22.2[1][8]
4.2[4]

2008 ST291, also written as 2008 ST291, is a trans-Neptunian object with an absolute magnitude of 4.2,[4] making it possibly a dwarf planet.[9]

Size estimate[edit]

2008 ST291 is estimated to be about 612 kilometres (380 mi) in diameter, assuming a typical albedo of 0.09 for trans-Neptunian objects.[6] However, because its albedo is unknown and it has an absolute magnitude of 4.3,[4] it could be anywhere between 370 to 820 km in diameter.[5]

Distance[edit]

2008 ST291, currently 59.0 AU from the Sun,[8] came to perihelion around 1954[4] and will have moved beyond a distance of 60 AU by 2016. It takes over one thousand years to orbit the Sun. Of the known and suspected dwarf planets, only Sedna and 2005 QU182 are known to have longer orbits.

2008 ST291 has only been observed 26 times over three oppositions and has an orbit quality of 4 (0 being best; 9 being worst).[4]

The orbit of 2008 ST291 compared to Pluto and Neptune

See also[edit]

References[edit]

  1. ^ a b "MPEC 2009-V68 : 2008 ST291". IAU Minor Planet Center. 2009-11-14. Retrieved 2009-12-06. 
  2. ^ "List Of Centaurs and Scattered-Disk Objects". Minor Planet Center. Retrieved 2009-12-06. 
  3. ^ Marc W. Buie. "Orbit Fit and Astrometric record for 08ST291" (last observation: 2010-10-09 using 20 of 23 observations over 2.04 years). SwRI (Space Science Department). Retrieved 2009-12-06. 
  4. ^ a b c d e f g "JPL Small-Body Database Browser: (2008 ST291)" (last observation: 2010-10-09; arc: 2.04 years). Retrieved 2008-12-06. 
  5. ^ a b "Absolute Magnitude (H)". NASA/JPL. Archived from the original on 26 November 2009. Retrieved 2009-12-06. 
  6. ^ a b Dan Bruton. "Conversion of Absolute Magnitude to Diameter for Minor Planets". Department of Physics & Astronomy (Stephen F. Austin State University). Archived from the original on 10 December 2008. Retrieved 2008-12-09. 
  7. ^ Assuming an albedo of 0.09
  8. ^ a b "AstDyS 2008 ST291 Ephemerides". Department of Mathematics, University of Pisa, Italy. Retrieved 2014-03-28. 
  9. ^ "How many dwarf planets are there in the outer solar system?". Gps.caltech.edu. 2015-07-21. Retrieved 2015-07-22. 

External links[edit]