Observation of the planetoid Ernestina with the 70cm-telescope

The movie on the left is the result of 6 hours of observation of the planetoid '(698) Ernestina', performed by Rainer Arlt on February 15, 2002 with the 70cm-telescope.

Ernestina is located in the center of the image. Clearly visible is its motion with respect to the background-stars, which are immobile with respect to the Earth.

During the observation Ernestina varied in brightness (the sinusoidal curve in the lower left).
This is explained by Ernestina not being spherical but prolate - similarly to the object shown in the lower right (planetoid Ida, ©NASA/JPL) - and rotating, thus causing the irradiated surface visible from Earth varying with time.

Last change 2005/10/27, A. Staude