NASA Hubble Space Telescope Captures Spectacular Images of Pulsating Star (Video)

NASA's Hubble Space Telescope has captured a series of new and spectacular images. It's caught the variable star RS Puppis over a period of five weeks, showing the star growing brighter and dimmer as it pulsates. The pulsations are a stunning example of a phenomenon known as light echo, where light appears to reverberate through the murky environment around the star.

A star is stable throughout most of its life. It slowly consumes the fuel at its core, shining brightly in the depths of space. Yet once most of this hydrogen has been consumed, stars begin to evolve and turn into pulsating stars. They become unstable as they expand and shrink over a number of days or weeks, growing brighter and dimmer as they do so.

This is exactly what's happening with RS Puppis, a type of variable star known as Cepheid variable. Cepheids have relatively long periods and RS Puppis varies in brightness by almost a factor of five every 40 or so days. Yet RS Puppis is unusual since it's shrouded by a nebula, thick dark clouds of gas and dust. Even so, Hubble was able to capture snapshots of this star at different stages in its cycle.

The apparent motion seen in the Hubble observations is a good example of a light echo. The dusty environment around the star enables this effect to be shown with stunning clarity. As the star expands and brightens, you can see some of the light after it is reflected from progressively more distant shells of dust and gas surrounding the star, creating the illusion of gas moving outward.

This particular effect isn't just stunning to watch, though. It also has important implications for finding out the intrinsic brightness of the pulsations. This property allows astronomers to use them as cosmic distance markers, which means that studying stars like RS Puppis helps astronomers measure and understand the scale of the universe.

Want to see the video of the star? Check it out below, courtesy of NASA.