Observing

See asteroid 2012 TC4’s close brush with Earth on 11-12 October

11 October 2017 Ade Ashford

At 6:42am BST on Thursday, 12 October our best orbit prediction for a 20-metre-wide space rock designated 2012 TC4 indicates that it will hurtle by Earth just 43,800 kilometres (27,215 miles) above the ocean between Australia and Antarctica. If UK skies are clear on 11 October and you have an 8-inch or larger telescope, you might just see it too.

News

Mysterious dimming of Tabby’s Star may be caused by dust

7 October 2017 Astronomy Now

One of the most mysterious stellar objects may be revealing some of its secrets at last. Called KIC 8462852, also known as Boyajian’s Star, or Tabby’s Star, the object has experienced unusual dips in brightness — NASA’s Kepler space telescope even observed dimming of up to 20 percent over a matter of days. In addition, the star has had much subtler but longer-term enigmatic dimming trends, with one continuing today.

Observing

See the International Space Station pass overhead from the UK tonight

5 October 2017 Ade Ashford

Urban dwellers may resign themselves to spotting the Moon, planets and the brightest stars with the unaided eye on a clear night, but every so often a bright satellite will catch your attention as it glides silently across the sky. The brightest is the 400-tonne International Space Station (ISS) whose orbit carries it directly overhead as seen from the British Isles and parts of Western Europe tonight.

News

JWST launch slips to early 2019

5 October 2017 Stephen Clark

Extra testing of the James Webb Space Telescope and delays in assembling the powerful observatory will push back the $10 billion mission’s launch by at least six months to early 2019, officials announced last week as the telescope successfully completed an extensive performance test inside a cryogenic vacuum chamber in Houston.

Picture This

Enceladus’ phantom limb

4 October 2017 Astronomy Now

The brightly lit limb of a crescent Enceladus looks ethereal against the blackness of space. The rest of the moon, lit by light reflected from Saturn, presents a ghostly appearance.

News

Hubble observes the farthest active inbound comet yet seen

4 October 2017 Astronomy Now

NASA’s Hubble Space Telescope has photographed the farthest active inbound comet ever seen, at a whopping distance of 1.5 billion miles from the Sun. Slightly warmed by the remote Sun, it has already begun to develop an 80,000-mile-wide fuzzy cloud of dust, called a coma, enveloping a tiny, solid nucleus of frozen gas and dust.