(9942) 1989 TM1

It was discovered on 8 October 1989, by Japanese astronomers Nobuhiro Kawasato and Tsutomu Hioki at the Okutama Observatory (877) in Japan.

[1] The asteroid was predicted to cross the focal plane array of the Infrared Astronomical Satellite (IRAS).

According to the "missed predictions file" of the supplemental IRAS minor planet survey (SIMPS), the body was expected to have a diameter of 13.5 kilometers and an absolute magnitude of 13.20.

[7] Based on an absolute magnitude of 13.99, and an assumed standard albedo for stony asteroids of 0.20, the Collaborative Asteroid Lightcurve Link calculated a much smaller diameter of 4.7 kilometers,[3] which agrees with a diameter of 4.1 kilometers, found by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission.

[4] In October 2010, a rotational lightcurve for this asteroid was obtained from photometric observations at the Palomar Transient Factory in California.