GALEX – Astronomy Now

Mini-flares potentially jeopardise habitability of planets circling red dwarf stars

11 June 2017 Astronomy Now

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?

Starvation diet for supermassive black hole dims brilliant galaxy

10 November 2016 Astronomy Now

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.

‘Frankenstein’ galaxy UGC 1382 surprises astronomers

13 July 2016 Astronomy Now

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.

Hubble reveals galaxy gas flow and star birth regulated by black-hole jets

10 August 2015 Astronomy Now

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.

Galaxy’s cannibalistic snacking habits revealed

23 May 2015 Astronomy Now

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.

Astronomers upgrade their cosmic light bulbs for studying the fabric of space

27 March 2015 Astronomy Now

Researchers identify the best Type Ia supernovae for gauging cosmic distances, potentially improving these measurements with a precision of more than two times that achieved before, up to six billion light-years away. These findings will help light the way to understanding dark energy.