Chemical Surprise Found in Crab Nebula: find involves a noble gas called Argon, named for its chemical aloofness after the Greek word for "inactive." Noble gases rarely engage in chemical reactions. They prefer to go it alone. A new study, led by Michael Barlow from Univ College London, & based on spectral data from Herschel, found the first evidence of such a noble gas-based compound in space, a molecule called argon hydride. The results are published in the journal Science.