Water has been predicted to be almost absent in carbon-rich stars, so the detection of water vapour around the ageing carbon star IRC + 10216 challenged our understanding of the chemistry in old stars. Several explanations for the water have been postulated, but with only one water line detected it is difficult to discriminate between them. Now, dozens of water vapour lines have been detected in the far-infrared and sub-millimetre spectrum of IRC + 10216.
- L. Decin
- M. Agúndez
- C. Waelkens