Take a look at Betelgeuse like you’ve never seen it before. Betelgeuse is one of the brightest stars in the sky and the red jewel in the crown of Orion. It’s the prototypical red supergiant star – a cool, bloated star that’s approaching the end of its lifetime. As it runs out of fuels to burn inside its core, the star struggles to hold on to its outer layers and ejects huge quantities of material as it approaches its final end, a cataclysmic supernova.
The small inner disk shows a near-infrared image taken with the adaptive optics imager NACO on VLT in Chile. These observations were the subject of a 2009 paper in Astronomy & Astrophysics by Pierre Kervella of LESIA (Paris) and collaborators.
The wider nebula is seen in more recent images from mid-infrared instrument VISIR, also on VLT, taken in the 7-20 micron range. The outer nebula shows lots of structure that seems to mirror the inner features, and is composed of all kinds of heavy processed material typical of evolved high-mass stars – silicates and alumina dust. This is the stuff that enriches the interstellar medium and allows the formation of rocky bodies like our Earth in further generations of stars.
The new mid-infrared observations are described in the team’s second paper, published this week in A&A.
The nebula, measuring several arcseconds across, is invisible at optical wavelengths. Because it’s so bright in the IR and large in size, Betelgeuse is an excellent target for high-resolution interferometric observations, like we’re planning with Gravity for the VLT Interferometer; indeed, several authors of these Betelgeuse papers are members of the Gravity team.
Image: ESO/P. Kervella
Kervella, P., Perrin, G., Chiavassa, A., Ridgway, S., Cami, J., Haubois, X., & Verhoelst, T. (2011). The close circumstellar environment of Betelgeuse. II. Diffraction-limited spectro-imaging from 7.76 to 19.50 microns with VLT/VISIR Astronomy & Astrophysics DOI: 10.1051/0004-6361/201116962 [astro-ph]
Kervella, P., Verhoelst, T., Ridgway, S., Perrin, G., Lacour, S., Cami, J., & Haubois, X. (2009). The close circumstellar environment of Betelgeuse Astronomy and Astrophysics, 504 (1), 115-125 DOI: 10.1051/0004-6361/200912521