This video shows Asteroid 2000 PH5 moving against the background stars and galaxies over a period of 2 hours. It was made in 2004 using the European Southern Observatory’s 8.2-m Very Large Telescope array in Chile. As the object moves from right to left in the lower half of the frame, one can see the asteroid’s brightness changing periodically. The rapid brightness modulations are caused by the asteroid’s rotation. It’s unusual to see this directly in a ground-based observation, but the stable conditions at the VLT site and the power of the telescope allowed this modulation to show up quite well.
Video Credit: A. Fitzsimmons