The star V838 Monocerotis, c 2005.
© National Aeronautics & Space Administration / Science & Society
This Hubble Space Telescope image of the star V838 Monocerotis (V838 Mon) reveals dramatic changes in the illumination of surrounding dusty cloud structures. The effect, called a light echo, has been unveiling never-before-seen dust patterns ever since the star suddenly brightened for several weeks in early 2002. The illumination of interstellar dust comes from the red supergiant star at the middle of the image, which gave off a pulse of light, somewhat similar to setting off a flashbulb in a darkened room. The dust may have been ejected during a previous explosion, similar to the 2002 event.