99942 Apophis

Tags: Planet.

99942 Apophis (/əˈpɒfɪs/ previously known by its provisional designation 2004 MN4) is a near-Earth asteroid that caused a brief period of concern in December 2004 because initial observations indicated a probability of up to 2.7% that it would hit Earth in 2029. Additional observations provided improved predictions that eliminated the possibility of an impact on Earth or the Moon in 2029.

apoapsis (km)

1.64334e+11

average speed (km/s)

110621.0

mass (kg)

4000.0

orbital period (μ)

2.79517e+07

periapsis (km)

1.11609e+11

temperature (K)

270.0

absolute magnitude

19.7

albedo

0.23

discovery date

2004-06-19

discoverer

David J. Tholen, Roy A. Tucker, Fabrizio Bernardi

epoch

(Uncertainty=0), JD 2454383.5 (October 12 2007)

escape velocity (kmh)

0.52

rotation period (s)

109440.0