17939 1999 HH8 is a main belt asteroid with an estimated diameter of 5 km. It was discovered on September 24 1960, by van Houten, C. J., van Houten-Groeneveld, I., Gehrels, T. at Palomar. The semi-major axis is 2.38 AU, the eccentricity is 0.105 and the inclination is 4.74 degrees.
Observations of this asteroid were made on two nights during May 2011 when it was in the same field as another asteroid I was studying. Analysis of the data indicated a period of 5.015 hours.