News – Page 183 – Astronomy Now

The closest rocky, transiting exoplanet found in Cassiopeia

31 July 2015 Astronomy Now

Northern Hemisphere astronomers are familiar with the W-shaped star pattern of Cassiopeia, a circumpolar constellation near the Pole Star that never sets for latitudes north of 35°. Tucked next to one leg of the W lies a modest 5th-magnitude star named HD 219134 that has been hiding a secret.

“Failed stars” host powerful auroral displays

30 July 2015 Astronomy Now

Brown dwarfs are relatively cool, dim objects that are too massive to be planets, yet they are too small to sustain hydrogen fusion reactions. By observing a brown dwarf 20 light-years away, researchers have found another feature that makes these so-called failed stars more like supersized planets — they host powerful aurorae near their magnetic poles.

Unusual red arcs discovered on icy Saturnian moon

30 July 2015 Astronomy Now

Like graffiti sprayed by an unknown artist, unexplained narrow, arc-shaped, reddish streaks are visible on the surface of Saturn’s icy moon Tethys in new, enhanced-colour images from NASA’s Cassini spacecraft. The red arcs are among the most unusual colour features on Saturn’s moons to be revealed by Cassini’s cameras.

The heart of Pluto in high-resolution

29 July 2015 Stephen Clark

The icy plains of Pluto resolved by NASA’s New Horizons spacecraft stretch as wide as Texas, enveloping mountain ranges and bizarre hilly outcrops in a mosaic revealing one lobe of the distant world’s heart-shaped reservoir of exotic frozen carbon monoxide, nitrogen and methane.

New names and insights at dwarf planet Ceres

29 July 2015 Astronomy Now

Colourful new maps of Ceres, based on data from NASA’s Dawn spacecraft, showcase a diverse topography, with height differences between crater bottoms and mountain peaks as great as 9 miles (15 kilometres). Some of these craters and other features now have official names, inspired by spirits and deities relating to agriculture from a variety of cultures.

Fossil globular star clusters reveal their age

28 July 2015 Astronomy Now

Using a new age-dating method and the W. M. Keck Observatory, an international team of astronomers have determined that globular star clusters formed in two distinct epochs — 12.5 and 11.5 billion years ago. They formed alongside galaxies, rather than prior to galaxies, as previously thought.

Impact of cosmic wind on galaxy evolution revealed

27 July 2015 Astronomy Now

Astronomers have long known that powerful cosmic winds can sometimes blow through galaxies, sweeping out interstellar material and stopping future star formation. A Yale University analysis of one such event in a nearby galaxy provides an unprecedented look at the process, offering a clearer snapshot of how it happens.

New Horizons discovers flowing ices on Pluto

25 July 2015 Astronomy Now

NASA’s New Horizons mission has found evidence of exotic ices flowing across Pluto’s surface, at the left edge of its bright heart-shaped area. New close-up images from the spacecraft’s Long-Range Reconnaissance Imager (LORRI) reveal signs of recent geologic activity, something scientists hoped to find but didn’t expect.

Simulated map of missing satellite galaxies could answer dark matter puzzle

23 July 2015 Astronomy Now

A ripple in the outskirts of the Milky Way led Rochester Institute of Technology astrophysicist Sukanya Chakrabarti to a previously undetected dwarf galaxy hidden under a veil of dark matter. Now Chakrabarti is refining her technique to uncover dwarf galaxies and understand dark matter by simulating the evolutionary histories of galactic discs and their satellite populations.

New Kepler planet could be Earth’s closest cousin yet

23 July 2015 Keith Cooper

A super-earth discovered by NASA’s Kepler Space Telescope and orbiting an older version of our Sun, is tantalising astronomers as potentially being the closest thing to a world like Earth.