1508 Kemi, provisional designation 1938 UP, is an eccentric, carbonaceous asteroid and one of the largest Mars-crossers, approximately 17 kilometers in diameter.

[2] Kemi was discovered on 21 October 1938, by Finnish astronomer Heikki Alikoski at the Iso-Heikkilä Observatory in Turku, Finland.

[3] It was independently discovered by Hungarian astronomer György Kulin at Konkoly Observatory near Budapest on 30 October 1938.

[1] In the Tholen classification, the body's spectral type is ambiguous (BCF), closest to that of a bright carbonaceous B-type and somewhat similar to a C- and F-type asteroid.

Analysis of the lightcurves gave a consolidated rotation period of 9.196 hours with a brightness variation between of 0.25 and 0.55 magnitude (U=2/3/3/2).