Cool dwarf stars are hot targets for exoplanet hunting right now. The discoveries of planets in the habitable zones of the TRAPPIST-1 and LHS 1140 systems, for example, suggest that Earth-sized worlds might circle billions of red dwarf stars, the most common type of star in our galaxy. But, like our own sun, many of these stars erupt with intense flares. Are red dwarfs really as friendly to life as they appear, or do these flares make the surfaces of any orbiting planets inhospitable?
Astronomers may have solved the mystery of the peculiar volatile behaviour of a supermassive black hole at the centre of a galaxy known as Markarian 1018 some 590 million light-years away. Combined data from NASA’s Chandra X-ray Observatory and other observatories suggest that the black hole is no longer being fed enough fuel to make its surroundings shine brightly.
About 250 million light-years away, there’s a neighbourhood of our universe that astronomers had considered quiet and unremarkable. But now, scientists have uncovered an enormous, bizarre galaxy possibly formed from the parts of other galaxies. Some 718,000 light-years across, UGC 1382 is more than seven times wider than the Milky Way.
Astronomers have uncovered a unique process for how the universe’s largest elliptical galaxies continue making stars long after their peak years of star birth. NASA’s Hubble Space Telescope revealed brilliant knots and chains of hot, blue stars forming along the jets of active black holes found in the centres of giant elliptical galaxies.
A team of Australian and Spanish astronomers have caught a greedy galaxy gobbling on its neighbours and leaving crumbs of evidence about its dietary past. Their successful and novel approach to investigating how galaxies grow is being used in a new program to further refine the best models of galaxy evolution.