Strange Case of the Pulsating Star

News from the Hubble Space Telescope, and Hubblecast. The great observatory has observed the variable star RS Puppis over a period of five weeks, showing the star growing brighter and dimmer. These pulsations have created a stunning example of a phenomenon known as a light echo, where light appears to reverberate through the murky environment around the star. A pulsating star forms when most of its hydrogen fuel has been consumed. It then becomes unstable, expanding and shrinking over a number of day