Hairy Woodpecker

2013 ND₁₅ (also written 2013 ND15) is an asteroid that is a temporary trojan of Venus, the first known Venus trojan.^[6]

2013 ND₁₅ was discovered on 13 July 2013 by N. Primak, A. Schultz, T. Goggia and K. Chambers, observing for the Pan-STARRS project. As of September 2014, it has been observed 21 times with a data-arc span of 26 days. It is an Aten asteroid and its semi-major axis (0.7235 AU) is very similar to that of Venus but it has high eccentricity (0.6115) and small orbital inclination (4.794°). With an absolute magnitude of 24.1, it has a diameter in the range 40–100 m (for an assumed albedo range of 0.04-0.20).

2013 ND₁₅ has been identified as a Venus trojan following a tadpole orbit around Venus' Lagrangian point L₄.^[6] Besides being a Venus co-orbital, this asteroid is also a Mercury crosser and an Earth crosser. 2013 ND₁₅ exhibits resonant (or near-resonant) behavior with Mercury, Venus and Earth.^[6] Its short-term dynamical evolution is different from that of the other three Venus co-orbitals, 2001 CK32, Zoozve, and 2012 XE133.^[6]

2013 ND₁₅ is not included in the Minor Planet Center list of potentially hazardous asteroids (PHAs) because its absolute magnitude is greater than 22.0, even though it comes to within 0.05 AU of Earth periodically. It approached Earth at 0.077 AU on 21 June 2016.

• (322756) 2001 CK32
• 524522 Zoozve
• 2012 XE133

Further reading

• Understanding the Distribution of Near-Earth Asteroids Bottke, W. F., Jedicke, R., Morbidelli, A., Petit, J.-M., Gladman, B. 2000, Science, Vol. 288, Issue 5474, pp. 2190–2194.
• A Numerical Survey of Transient Co-orbitals of the Terrestrial Planets Christou, A. A. 2000, Icarus, Vol. 144, Issue 1, pp. 1–20.
• Debiased Orbital and Absolute Magnitude Distribution of the Near-Earth Objects Bottke, W. F., Morbidelli, A., Jedicke, R., Petit, J.-M., Levison, H. F., Michel, P., Metcalfe, T. S. 2002, Icarus, Vol. 156, Issue 2, pp. 399–433.
• Transient co-orbital asteroids Brasser, R., Innanen, K. A., Connors, M., Veillet, C., Wiegert, P., Mikkola, S., Chodas, P. W. 2004, Icarus, Vol. 171, Issue 1, pp. 102–109.
• The population of Near Earth Asteroids in coorbital motion with Venus Morais, M. H. M., Morbidelli, A. 2006, Icarus, Vol. 185, Issue 1, pp. 29–38.
• Asteroid 2013 ND15: Trojan companion to Venus, PHA to the Earth de la Fuente Marcos, C., de la Fuente Marcos, R. 2013, Monthly Notices of the Royal Astronomical Society, Vol. 439, Issue 3, pp. 2970–2977.

• Discovery MPEC
• 2013 ND₁₅ data at MPC
• List of Potentially Hazardous Asteroids (PHAs)
• 2013 ND15 at NeoDyS-2, Near Earth Objects—Dynamic Site
  • Ephemerides · Observation prediction · Orbital info · MOID · Proper elements · Observational info · Close approaches · Physical info · Orbit animation
• 2013 ND15 at ESA–space situational awareness
  • Ephemerides · Observations · Orbit · Physical properties · Summary
• 2013 ND15 at the JPL Small-Body Database
  • Close approach · Discovery · Ephemeris · Orbit diagram · Orbital elements · Physical parameters