(418993) 2009 MS9

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
(418993) 2009 MS9
Discovered by CFHT (568)
Discovery date 25 June 2009
MPC designation (418993) 2009 MS9
Centaur (DES)[3]
Orbital characteristics[4]
Epoch 13 January 2016 (JD 2457400.5)
Uncertainty parameter 2
Observation arc 2352 days (6.44 yr)
Aphelion 696 AU (barycentric 2050)[a]
684 AU
Perihelion 11.002 AU (1.6459 Tm)
353 AU (barycentric 2050)[a]
347.6 AU
Eccentricity 0.96835
6481.05 yr (2367202 d)
0° 0m 0.547s / day
Inclination 68.056°
Physical characteristics
Dimensions 30–60 km[5]

(418993) 2009 MS9, provisionally known as 2009 MS9, is a centaur roughly 30–60 km in diameter. It has a highly inclined orbit and a barycentric semi-major axis (average distance from the Sun) of ~353 AU.[a]

2009 MS9 has a well determined orbit and has been assigned a minor planet number. Objects such 2009 MS9 may be the origin of Halley-type comets.[2]

It came to perihelion in February 2013 at a distance of 11 AU from the Sun (outside the orbit of Saturn).[4] As of 2016, it is 12 AU from the Sun.[6]

It will not be 50 AU from the Sun until 2047. After leaving the planetary region of the Solar System, 2009 MS9 will have a barycentric aphelion of 696 AU with an orbital period of 6640 years.

In a 10 million year integration of the orbit, the nominal (best-fit) orbit and both 3-sigma clones remain outside 8.3AU (qmin) from the Sun.[3]

Orbital evolution
Epoch Barycentric
Aphelion (Q)
1950 694 6610
2050 696 6640


  1. ^ a b c Given the orbital eccentricity of this object, different epochs can generate quite different heliocentric unperturbed two-body best-fit solutions to the semi-major axis and orbital period. For objects at such high eccentricity, the Sun's barycentric coordinates are more stable than heliocentric coordinates. Using JPL Horizons, the barycentric semi-major axis is approximately 353 AU.[7]


  1. ^ "MPEC 2009-S59 : 2009 MS9". IAU Minor Planet Center. 2009-09-20. Retrieved 2016-02-11.  (K09M09S)
  2. ^ a b Parker, Joel; Jones, Lynne; Petit, Jean-Marc; Rousselot, Philippe (2010). "Scrutinizing the Extreme TNO 2009 MS9". National Optical Astronomy Observatory (NOAO). Bibcode:2010noao.prop..285P. 
  3. ^ a b Marc W. Buie. "Orbit Fit and Astrometric record for 418993". SwRI (Space Science Department). Retrieved 2016-02-11. 
  4. ^ a b c "JPL Small-Body Database Browser: 418993 (2009 MS9)" (last observation: 2015-12-03; arc: 6.44 yr). Jet Propulsion Laboratory. Retrieved 8 April 2016. 
  5. ^ "Absolute Magnitude (H)". NASA/JPL. Retrieved 2016-02-04. 
  6. ^ a b "AstDyS (418993) 2009MS9 Ephemerides". Department of Mathematics, University of Pisa, Italy. Retrieved 2016-02-11. 
  7. ^ Horizons output. "Barycentric Osculating Orbital Elements for 2009 MS9". Retrieved 2016-02-11.  (Solution using the Solar System Barycenter and barycentric coordinates. Select Ephemeris Type:Elements and Center:@0)

External links[edit]