. While studying the dust content of the Crab Nebula with the Herschel Space Observatory, astronomers have detected emission lines from argon hydride, a molecular ion containing the noble gas argon. This is the first detection of a noble-gas based compound in space. This image shows a composite view of the supernova remnant as viewed by the Herschel and the Hubble Space Telescope. ESA/Herschel/PACS/MESS Key Programme Supernova Remnant Team; NASA/ESA/A. Loll/J. Hester (Arizona State University)