Herschel Finds Water Around a Carbon Star

There’s something strange going on around the red giant star CW Leonis (a.k.a. IRC+10216). Deep within the star’s carbon-rich veil, astronomers have detected water vapor where no water should be. CW Leonis is similar in mass to the sun, but much older and much larger. It is the nearest red giant to the sun, and [...]

Herschel image of the carbon star CW Leonis. The arc visible to the left of the star is a bow shock, where the stellar wind encounters the interstellar medium. Water vapor has been discovered near the star at temperatures up to 1000 K. ESA/PACS/SPIRE/MESS ConsortiaThere’s something strange going on around the red giant star CW Leonis (a.k.a. IRC+10216). Deep within the star’s carbon-rich veil, astronomers have detected water vapor where no water should be.CW Leonis is similar in mass to the sun, but much older and much larger. It is the nearest red giant to the sun, and in its death throes it has hidden itself in a sooty, expanding cloud of carbon-rich dust. This shroud makes CW Leonis almost invisible to the naked eye, but at some infrared wavelengths it is the brightest object in the sky.Water was originally discovered around CW Leonis ...