2018 CN2


2018 CN2
2018 CN2 orbit.png
The orbit before and after flyby, with positions on 1 February 2018, before flyby
Discovered byMount Lemmon Srvy.
Discovery siteMount Lemon Obs.
Discovery date8 February 2018
(first observed only)
2018 CN2
NEO · Apollo[1][2]
Earth- and Mars crosser
Orbital characteristics[2]
Epoch 23 March 2018 (JD 2458200.5)
Uncertainty parameter 7
Observation arc1 day
Aphelion1.7740 AU
Perihelion0.6335 AU
1.2037 AU
1.32 yr (482 days)
0° 44m 46.68s / day
Earth MOID7.7×10−5 AU (0.03 LD)
Physical characteristics
Mean diameter
5–16 m[3]
9 m (est. at 0.20)[4]
17 m (est. at 0.057)[4]

2018 CN2 is a very small asteroid, classified as a near-Earth object of the Apollo group, approximately 5 to 16 meters in diameter. It was first observed by astronomers of the Mount Lemmon Survey at Mount Lemmon Observatory, Arizona, on 8 February 2018, one day prior its close encounter with Earth at 0.18 lunar distances.[1]

Orbit and classification

2018 CN2 is a member of the Apollo asteroids, which cross the orbit of Earth. Apollo's are the largest group of near-Earth objects with nearly 10 thousand known objects.

Based on a high orbital uncertainty, this asteroid orbits the Sun at a distance of 0.63–1.77 AU once every 16 months (482 days; semi-major axis of 1.20 AU). Its orbit has an eccentricity of 0.47 and an inclination of 26° with respect to the ecliptic.[2] With an aphelion of 1.77 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 8 February 2018.[1]

Close encounters

The object has an exceptionally low minimum orbital intersection distance with Earth of 11,500 km (0.000077 AU), or 0.03 lunar distances (LD).[2]

2018 flyby

On 9 February 2018, 2018 CN2 passed at a nominal distance of only 69,900 km; 43,400 mi (0.000466964 AU) from Earth at 7:25 UTC.[2] This corresponds to 0.18 LD. Based on the body's high orbital uncertainty, all subsequent close encounters in 2022, 2023, 2026, 2027 and 2031, are projected to occur at a distance of more than 15 million kilometers (0.1 AU; 39 LD).[2]

2018 flyby: Its path across the sky on 9 February was north to south (15 minute positions shown) (left). Seen from space, it passes just outside geosynchronous orbit (right).

Physical characteristics

The Minor Planet Center estimates a diameter of 5–16 meters.[3] Based on a generic magnitude-to-diameter conversion, 2018 CN2 measures between 9 and 17 meters in diameter, for an absolute magnitude of 27.653, and an assumed albedo between 0.057 and 0.20, which represent typical values for carbonaceous and stony asteroids, respectively.[4]

As of 2018, no rotational lightcurve of 2018 CN2 has been obtained from photometric observations. The body's rotation period, pole and shape remain unknown.[2]

Numbering and naming

This minor planet has neither been numbered nor named.[1]

See also


  1. ^ a b c d e "2018 CN2". Minor Planet Center. Retrieved 15 February 2018.
  2. ^ a b c d e f g h "JPL Small-Body Database Browser: (2018 CN2)" (2018-02-09 last obs.). Jet Propulsion Laboratory. Retrieved 15 February 2018.
  3. ^ a b Minor Planet Center. "2018 CN2". Twitter. Retrieved 10 February 2018.
  4. ^ a b c "Asteroid Size Estimator". CNEOS NASA/JPL. Retrieved 15 February 2018.

External links

  • MPEC MPEC 2018-C76 : 2018 CN2, Minor Planet Electronic Circular, 10 February 2018
  • Asteroid 2018 CN2 close approach, International Asteroid Warning Network (IWAN)
  • Asteroid 2018 CN2 flew past Earth at 0.18 LD, discovered one day before closest approach, The Watchers, 11 February 2018
  • 2018 CN2 at NeoDyS-2, Near Earth Objects—Dynamic Site
    • Ephemeris · Obs prediction · Orbital info · MOID · Proper elements · Obs info · Close · Physical info · NEOCC
  • 2018 CN2 at the JPL Small-Body Database
    • Close approach · Discovery · Ephemeris · Orbit diagram · Orbital elements · Physical parameters