Thousands of years ago, a flash of light reached Earth, a beacon heralding the death throes of a massive star. Located in the Large Magellanic Cloud, a companion galaxy to the Milky Way, the star left behind a huge cloud of chaotic, seemingly wispy gas, seen here in an image captured by the Hubble Space Telescope, that was blown away before and just after the sun exploded. The gas will provide the raw material for another generation of stars, mirroring the process that led to the Sun’s formation and the planets in Earth’s solar system. The doomed star’s core, meanwhile, its nuclear fuel exhausted, succumbed to gravity and collapsed on itself, likely forming a compact, spinning pulsar. A pulsar does, in fact, lurk near the supernova remnant known as DEM L 190, completing one turn on its axis every eight seconds. Boasting a magnetic field thousands of times stronger than Earth’s, the pulsar is classified as a magnetar and may well be the remnant core of the star that exploded.
Galaxy clusters are enormous collections of hundreds or even thousands of galaxies and vast reservoirs of hot gas embedded in massive clouds of dark matter. To learn more about clusters, including how they grow via collisions, astronomers have used some of the world’s most powerful X-ray, optical and radio telescopes. The name for this galaxy cluster project is the “Frontier Fields”.
This Hubble Space Telescope image shows globular cluster NGC 1783 in the Southern Hemisphere constellation of Dorado. NGC 1783 lies within the Large Magellanic Cloud, a satellite galaxy of our Milky Way, some 160,000 light-years from Earth. NGC 1783 is thought to be less than 1.5 billion years old — very young for a globular cluster.
Water is a hot topic in the study of exoplanets, including “hot Jupiters” close to their parent stars that can reach a scorching 1,100 °C, meaning any water they host would take the form of vapour. Hot Jupiters have been found with water in their atmospheres, but others appear to have none. NASA scientists wanted to find out what the atmospheres of these giant worlds have in common.