Using the European Herschel space telescope, an international
team including astronomers at Observatoire de Paris, Institut de
Radio Astronomie Millimetrique and Observatoire de Grenoble in
France observed hot water vapor formed somewhere that was
previously thought to be impossible: deep into the atmosphere of
a red giant pulsating carbon star, CW Leonis. This result,
published in the 2 September 2010 issue of Nature magazine,
should help to understand how this type of evolved star produces
and expels key ingredients for all known forms of life. The
major building blocks of life on Earth are water and carbon-
based molecules, synthesized in large quantities by stars like
the Sun at the end of their lives. When they age, these stars
become red giants and puff out their atmospheres. These have
previously been seen to contain either water or carbon-based
molecules, and it was thought that these two types of species
could not co-exist. New results from the Photodetector Array
Camera Spectrometer PACS and Spectral