(419624) 2010 SO16

The orbit was described by Apostolos Christou and David Asher at the Armagh Observatory in Northern Ireland. The object has an absolute magnitude of 20.5. Observations by the discovering WISE telescope give a diameter of 357 meters and an albedo of 0.084.

2010 SO₁₆ has a horseshoe orbit that allows it to stably share Earth's orbital neighborhood without colliding with it. It is one of a handful of known asteroids with an Earth-following orbit, a group that includes 3753 Cruithne, and the only known asteroid in an horseshoe orbit with Earth. It is, however, neither an Aten asteroid nor an Apollo asteroid because the semi-major axis of its orbit is neither less than nor greater than 1 AU, but oscillates between approximately 0.996 and 1.004 AU, with a period of about 350 years. In its ~350 yr horseshoe cycle, it never approaches Earth more closely than about 0.15 AU, alternately trailing and leading.

According to various simulations 2010 SO₁₆ will remain in this orbit for at least 120,000 years and possibly for more than a million years, which is unusually stable compared to other similar objects. One reason for this stability is its low orbital eccentricity, ${\displaystyle <0.084}$ .

A precovery of 2010 SO₁₆ may have been located in a 2005 Spitzer Space Telescope image.

• 3753 Cruithne – a horseshoe companion of the Earth
• 2006 RH120 – a small asteroid that sometimes temporarily gets caught in Earth orbit
• 2002 AA29 – a horseshoe companion of the Earth
• Natural satellite
• 2001 GO2
• 2002 AA29
• 2003 YN107
• 2006 JY26
• 2012 FC71
• Orbital resonance

• (419624) 2010 SO16 at NeoDyS-2, Near Earth Objects—Dynamic Site
  • Ephemerides · Observation prediction · Orbital info · MOID · Proper elements · Observational info · Close approaches · Physical info · Orbit animation
• (419624) 2010 SO16 at ESA–space situational awareness
  • Ephemerides · Observations · Orbit · Physical properties · Summary
• (419624) 2010 SO16 at the JPL Small-Body Database
  • Close approach · Discovery · Ephemeris · Orbit diagram · Orbital elements · Physical parameters