2008 ST291

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
Minor planet
category		 TNO (SDO)[2][3]
Epoch February 8, 2011
Aphelion 159.12 AU (Q)
Perihelion 42.61 AU (q)
Semi-major axis 100.86 AU (a)
Eccentricity 0.5775
Orbital period 1013 yr
Mean anomaly 19.961° (M)
Inclination 20.75°
Longitude of ascending node 330.98°
Argument of perihelion 325.49°
Physical characteristics
Dimensions 380-860 km[4][5]
640 km[6][7]
Apparent magnitude ~22.1[1]
Absolute magnitude (H) 4.3[4]

2008 ST291, also written as 2008 ST291, is a trans-Neptunian object with an absolute magnitude of 4.4.[4] This makes it a dwarf-planet candidate.

Distance

It came to perihelion around 1954,[4] and is currently 56.8 AU from the Sun.

It has only been observed 23 times over three oppositions and has an orbit quality of 4 (0 being best; 9 being worst).[4]

Assuming a generic trans-Neptunian albedo of 0.09, it is about 583 km in diameter.[6] But since its true albedo is unknown and it has an absolute magnitude of 4.4,[4] it could easily be somewhere between 350 to 783 km in diameter.[5]

References

  1. ^ a b "MPEC 2009-V68 : 2008 ST291". IAU Minor Planet Center. 2009-11-14. http://minorplanetcenter.org/mpec/K09/K09V68.html. Retrieved 2009-12-06. 
  2. ^ "List Of Centaurs and Scattered-Disk Objects". Minor Planet Center. http://www.minorplanetcenter.org/iau/lists/Centaurs.html. Retrieved 2009-12-06. 
  3. ^ Marc W. Buie (2009-10-18 using 19 of 21 observations). "Orbit Fit and Astrometric record for 08ST291". SwRI (Space Science Department). http://www.boulder.swri.edu/~buie/kbo/astrom/08ST291.html. Retrieved 2009-12-06. 
  4. ^ a b c d e f g "JPL Small-Body Database Browser: (2008 ST291)". 2010-10-09 last obs. http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2008ST291. Retrieved 2008-12-06. 
  5. ^ a b "Absolute Magnitude (H)". NASA/JPL. http://neo.jpl.nasa.gov/glossary/h.html. 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). http://www.physics.sfasu.edu/astro/asteroids/sizemagnitude.html. Retrieved 2008-12-09. 
  7. ^ Assuming an albedo of 0.09

External links