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The red supergiant Betelgeuse (Alpha Orionis) is one of the brightest stars in the sky, and also one of the largest stars known, with a volume that could fill almost all of space within the orbit of Jupiter (shown by the little red circle at the centre of the image).
This is why, in the '80s, it was also one of the first stars for which surface details on the photosphere were imaged.
More recently, in July 2009, with the NACO instrument (an infrared spectrometer with adaptive optics) on ESO's Very Large Telescope, a number of extended plumes of gas were discovered around the disk of Betelgeuse, extending a few stellar diameters above the photosphere.
But the real surprise is the latest discovery, made with the VISIR instrument (VLT Imager and Spectrometer for mid Infra Red) shortly to be published in the journal Astronomy & Astrophysics, that reveals a gigantic nebular complex around Betelgeuse, the origin of which is connected to the current, transient evolutionary phase of the star.
Atmospheric and photospheric instability are a characteristic of supergiants, causing them to loose enormous quantities of material, and in the case of Betelgeuse, it is estimated that it loses a mass equal to that of the Sun in just 10,000 years.
The irregular appearance of the nebulosity in the above image shows that this loss of material into space has been quite asymmetrical.
The vaguely concentric structure is likely to be due to outburst events that effect specific areas of the surface, as would seem to be indicated by the apparent correspondence between the internal plumes and much larger external nebula, that stretches out to 60 billion kilometres from the stellar disk.
Amongst the material which makes up the nebula are large amounts of silicate and aluminium dust, the same materials that form a large part of the terrestrial crust and the other rocky planets of the solar system. This supports the long-standing hypothesis, that the existence of the Earth is ultimately thanks to the synthesis of these heavy elements, and their successive release into space, by massive stars such as Betelgeuse, billions of years in the past.
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