London - Betelgeuse is the second brightest star in the constellation of Orion, a red supergiant, one of the biggest stars known, and almost 1,000 times larger than our Sun.

It has also now been examined as it never has been before thanks to two international teams of astronomers using different state-of-the-art techniques on the Very Large Telescope at the European Southern Observatory (ESO), the foremost intergovernmental astronomy organization in Europe and the world’s most productive astronomical observatory.

One of these astronomers is Jan Cami from the Department of Physics and Astronomy at The University of Western Ontario.

“It sounds crazy to use one of the world’s largest telescopes to look at one of the biggest and brightest stars in the sky, yet that is exactly what we did,” explains Cami. ”We used the 8.2 meter VLT (Very Large Telescope) to look at Betelgeuse.”

The two independent teams of astronomers obtained the sharpest ever views of the supergiant star Betelgeuse, which show that the star has a vast plume of gas almost as large as our Solar System and a gigantic bubble boiling on its surface. These discoveries provide important clues to help explain how these mammoths lose mass at such a tremendous rate.

According to ESO, if Betelgeuse were at the centre of our Solar System it would extend out almost to the orbit of Jupiter, engulfing Mercury, Venus, Earth, Mars and the main asteroid belt.

“Betelgeuse is indeed a textbook example of a supernova progenitor and careful observations of this stellar behemoth are not only important to understand what goes on in and around these stars, but also to unravel the processes that ultimately lead to a supernova explosion,” says Cami, who adds a supernova progenitor is an early stage in supernova development similar to the caterpillar or larva stage during the metamorphosis of a fully developed butterfly.

This research was presented in two papers to appear in Astronomy and Astrophysics: “The close circumstellar environment of Betelgeuse: Adaptive optics spectro-imaging in the near-IR with VLT/NACO”, by Pierre Kervella et al., and “Spatially resolving the inhomogeneous structure of the dynamical atmosphere of Betelgeuse with VLTI/AMBER”, by Keiichi Ohnaka et al.

Images can be viewed at: http://www.flickr.com/photos/atwestern/