2018 CF₂

2018 CF₂

The orbit before and after its 2018-flyby
Discovery[1]
Discovered by	MLS
Discovery site	Mount Lemmon Obs.
Discovery date	7 February 2018
Designations
MPC designation	2018 CF2
Minor planet category	NEO · Apollo[1][2]
Orbital characteristics[2]
Epoch 23 March 2018 (JD 2458200.5)
Uncertainty parameter 7
Observation arc	2 days
Aphelion	2.7662 AU
Perihelion	0.9089 AU
Semi-major axis	1.8375 AU
Eccentricity	0.5054
Orbital period (sidereal)	2.49 yr (910 days)
Mean anomaly	29.432°
Mean motion	0° 23m 44.52s / day
Inclination	16.284°
Longitude of ascending node	137.68°
Argument of perihelion	320.19°
Earth MOID	0.00077 AU (0.30 LD)
Physical characteristics
Mean diameter	4–15 m[3] 7 m (est. at 0.20)[4] 14 m (est. at 0.057)[4]
Absolute magnitude (H)	28.036[2]

2018 CF₂ is a micro-asteroid and near-Earth object of the Apollo group on an eccentric orbit with has an estimated 4–15 meters (10–50 ft). It was first observed on 7 February 2018, by astronomers of the Mount Lemmon Survey at Mount Lemmon Observatory, Arizona, United States.^[1] The discovery occurred the day after its sub-lunar passage as it approached the Earth from a sunward direction, and this flyby altered the asteroid's orbit slightly.

2018 CF₂ belongs to the Apollo asteroids, the largest group of near-Earth objects with nearly 10 thousand known members, which cross the orbit of Earth.

Based on a high uncertainty, it orbits the Sun at a distance of 0.91–2.77 AU once every 2 years and 6 months (910 days; semi-major axis of 1.84 AU). Its orbit has an eccentricity of 0.51 and an inclination of 16° with respect to the ecliptic.^[2] With an aphelion of 2.77 AU, it is also a Mars-crosser, as it crosses the orbit of the Red Planet at 1.666 AU. The body's observation arc begins at Mount Lemmon with its first observation on 7 February 2018.^[1]

On 6 February 2018, 18:45 UTC, the day before its first observation, it had a flyby with the Earth at a nominal distance of 0.25 lunar distances (LD).^[3] Its next close approach to Earth is projected to occur on 23 January 2023, at 0.111 AU (43 LD).^[2] After the 2018-passage, the body's minimum orbital intersection distance with Earth increased to 0.30 LD (0.00077 AU).^[2]

2018 flyby: Path in sky with daily motion south to north (left). View of path across earth-moon system, moving from south to north (right).

The Minor Planet Center estimates a diameter of 4–15 meters (10–50 ft).^[3] Based on a generic magnitude-to-diameter conversion using an absolute magnitude of 28.036,^[2] the body measures between 7 and 14 meters in diameter for an assumed albedo of 0.057 and 0.20, which represent typical values for carbonaceous and stony asteroids, respectively.^[4]

As of 2018, no rotational lightcurve of 2018 CF₂ has been obtained from photometric observations. The body's rotation period, pole and shape remain unknown.^[2]

This minor planet has not yet been numbered.^[1]

• List of asteroid close approaches to Earth in 2018
• Gravity assist

Wikimedia Commons has media related to 2018 CF2.

• MPEC 2018-C69 : 2018 CF2, Minor Planet Electronic Circular, 10 February 2018
• Asteroid 2018 CF2 flew past Earth at 0.25 LD, one day before discovery, The Watchers, 11 February 2018
• 2018 CF2 at NeoDyS-2, Near Earth Objects—Dynamic Site
  • Ephemerides · Observation prediction · Orbital info · MOID · Proper elements · Observational info · Close approaches · Physical info · Orbit animation
• 2018 CF2 at the JPL Small-Body Database
  • Close approach · Discovery · Ephemeris · Orbit viewer · Orbit parameters · Physical parameters