In the Perseus arm of the Milky Way, in the constellation of Puppis, a half dozen vast “bubbles” of hydrogen gas, heated by intense ultraviolet radiation from nearby O-type stars, provide spectacular backdrops for stellar nurseries where new stars are being born. This glowing cloud, known as SH 2-305, is an emission nebula, or HII region, illuminated by at least two O-type stars and probably several others. Such stars live fast and die young, shining a million times brighter than the Sun with up to around 90 times the mass. This image was captured by the European Southern Observatory’s Cosmic Gems programme, an initiative to gather engaging imagery when science observations are not possible.
An international team of astronomers has discovered glowing gas clouds surrounding distant quasars. The new survey of these active galaxies indicates that haloes around quasars are far more common than expected. The properties of the haloes in this surprising find are also in striking disagreement with currently accepted theories of galaxy formation in the early universe.
Many galaxies blast huge, wide-angled flows of material outward from their centres, pushing to their outer edges enough dust and gas each year that otherwise would have formed more than a thousand stars the size of our Sun. A team led by University of Maryland scientists has found the driving force behind these massive molecular outflows.
An international team of astronomers has used the Atacama Large Millimetre/submillimetre Array (ALMA) to detect glowing oxygen in a distant galaxy seen just 700 million years after the Big Bang. This is the most distant galaxy in which oxygen has ever been unambiguously detected, and it is most likely being ionised by powerful radiation from young giant stars.