Asteroid streak

Asteroid streak

Fig. 13.13 . As an asteroid moves along its orbit it will produce an elongated trail in an image taken with a telescope following the background of "fixed" stars, which are not moving in this way. One previously unknown asteroid was discovered in 1998 as a long blue streak (top center) against the white background stars in this archival image taken by the Hubble Space Telescope. The bright asteroid has an estimated diameter of 2 kilometers, and was located at about 140 million kilometers from the Earth. (Courtesy of NASA/R. Evans and K. Stapelfeldt, JPL.)

Copyright 2010, Professor Kenneth R. Lang, Tufts University