News

NASA’s Fermi discovers the most extreme blazars yet

31 January 2017 Stephen Clark

NASA’s Fermi Gamma-ray Space Telescope has identified the farthest gamma-ray blazars, a type of galaxy whose intense emissions are powered by supersized black holes. Light from the most distant object began its journey to us when the universe was 1.4 billion years old, or nearly 10 percent of its present age.

News

Cassini offers best-ever view of Saturn’s rings

30 January 2017 Stephen Clark

A sequence of images captured by NASA’s Cassini spacecraft last month are the most detailed pictures ever taken of Saturn’s famous rings, revealing complex, unexplained bands and the movements of dozens of tiny icy moonlets spinning around the planet.

Observing

See the Mars-Venus-Moon conjunction of 31 January

30 January 2017 Ade Ashford

Dazzling Venus and much fainter Mars have a close encounter with a young Moon in the constellation of Pisces at UK dusk on Tuesday 31 January. The trio form an equilateral triangle small enough to be encompassed by the field of view of a 7x binocular low in the west-southwest for a couple of hours from 7pm GMT.

News

Cosmic lenses support finding on faster than expected expansion of the Universe

30 January 2017 Stephen Clark

By using galaxies as giant gravitational lenses, an international group of astronomers using the Hubble Space Telescope have made an independent measurement of how fast the Universe is expanding. The newly measured expansion rate for the local Universe is consistent with earlier findings. These are, however, in intriguing disagreement with measurements of the early Universe.

News

NASA resumes JWST vibration testing

25 January 2017 Stephen Clark

Vibration testing on the James Webb Space Telescope, the multibillion-dollar successor to Hubble, has resumed after engineers traced a problem that cropped up last month to a restraint holding part of the observatory’s giant segmented mirror in place for launch.

News

NuSTAR finds new clues to ‘chameleon supernova’

25 January 2017 Stephen Clark

“We’re made of star stuff,” astronomer Carl Sagan famously said. Nuclear reactions that happened in ancient stars generated much of the material that makes up our bodies, our planet and our solar system. When stars explode in violent deaths called supernovae, those newly formed elements escape and spread out in the universe.

News

Our galaxy’s black hole is spewing out planet-size ‘spitballs’

23 January 2017 Stephen Clark

Every few thousand years, an unlucky star wanders too close to the black hole at the center of the Milky Way. The black hole’s powerful gravity rips the star apart, sending a long streamer of gas whipping outward. That would seem to be the end of the story, but it’s not. New research shows that not only can the gas gather itself into planet-size objects, but those objects then are flung throughout the galaxy in a game of cosmic “spitball.”