Editing 2002 AA29 (section)

{{DISPLAYTITLE:{{mp|2002 AA|29}}}}
{{Infobox planet
| minorplanet=yes
| background=#FFC2E0
| name={{mp|2002 AA|29}}
| image= 2002AA29.gif
| image_scale =
| discovery_ref=<ref name="MPEC2002-A92"/>
| discoverer=[[LINEAR]]
| discovered=January 9, 2002
| alt_names=''none''
| mp_category=[[Aten asteroid]]
| orbit_ref=<ref name="jpldata"/>
| epoch=13 January 2016 ([[Julian day|JD]] 2457400.5)
| semimajor={{Convert|0.99259|AU|Gm|abbr=on}}
| perihelion={{Convert|0.97963|AU|Gm|abbr=on}}
| aphelion={{Convert|1.0055|AU|Gm|abbr=on|lk=on}}
| eccentricity=0.013047
| period=0.99 [[Julian year (astronomy)|yr]] (361.2 [[Julian year (astronomy)|d]])
| inclination=10.748°
| asc_node=106.38°
| arg_peri=101.75°
| mean_anomaly=310.32[[Degree (angle)|°]]
| avg_speed=29.784 km/[[second|s]]
| dimensions=~0.06 km<br /><100 metres<ref name=Connors2002/><br />25±5 metres<ref name="Icarus2"/>
| mass=~2.3×10<sup>8</sup> kg
| density=2 ? g/cm<sup>3</sup>
| surface_grav=~0.000 017 m/s<sup>2</sup>
| escape_velocity=~0.000 032 km/s
| rotation={{Convert|0.55|h|min|abbr=on|lk=on}}<ref name="jpldata"/>
| spectral_type=[[S-type asteroid]]<ref name="Icarus2"/>
| abs_magnitude=24.1
| albedo=0.2 ?
| single_temperature=~279 [[kelvin|K]]
| mean_motion={{Deg2DMS|0.99667|sup=ms}} /day
| observation_arc=736 days (2.02 yr)
| uncertainty=0
| moid={{Convert|0.0116565|AU|Gm|abbr=on}}
| jupiter_moid={{Convert|3.96814|AU|Gm|abbr=on}}
}}
'''{{mp|2002 AA|29}}''' ([[Astronomical naming conventions#Minor planets|also written]] '''2002 AA29''') is a small [[near-Earth asteroid]] that was discovered on January 9, 2002 by the [[Lincoln Near-Earth Asteroid Research|LINEAR]] ''(Lincoln Near Earth Asteroid Research)'' automatic sky survey. The diameter of the [[asteroid]] is only about {{convert|20|-|100|m|ft|sigfig=1}}. It revolves about the [[Sun]] on an almost circular orbit very similar to that of the [[Earth]]. This lies for the most part inside the Earth's orbit, which it crosses near the asteroid's furthest point from the Sun, the [[aphelion]]. Because of this orbit, the asteroid is classified as [[Aten asteroid|Aten type]],<ref name=jpldata/> named after the asteroid [[2062 Aten]].

A further characteristic is that its mean [[orbital period]] about the Sun is exactly one [[sidereal year]]. This means that it is locked into a relationship with the Earth, since such an orbit is only stable under particular conditions. As yet only a few asteroids of this sort are known, locked into a 1:1 [[Orbital resonance|resonance]] with the Earth. The first was [[3753 Cruithne]], discovered in 1986.

Asteroids that have a 1:1 orbital resonance with a planet are also called [[Co-orbital configuration|co-orbital objects]], because they follow the orbit of the planet. The most numerous known co-orbital asteroids are the so-called [[Trojan (astronomy)|trojans]], which occupy the L4 and L5 [[Lagrangian points]] of the relevant planet. However, {{mp|2002 AA|29}} does not belong to these. Instead, it follows a so-called [[horseshoe orbit]] along the path of the Earth.