Brilliant planet Venus attains its greatest elongation almost 47° west of the Sun at dawn in the UK on Sunday, 6 January. Find a location that offers you a view down to the southeast horizon around 7am GMT and you may catch a glimpse of Jupiter too. The planetary duo is currently 14 degrees apart – about one-and-a-half spans of a fist at arm’s length – but drawing nearer for a close conjunction on 22 January. AN graphic by Ade Ashford.It currently pays to be an early riser if you wish to see some spectacular planetary activity. Even casual skywatchers cannot fail to notice dazzling Venus hanging like a lantern, brighter than any other natural nighttime object except the Moon, low in the south-southeast at the start of nautical twilight around 90 minutes before sunrise in the UK (see our interactive Almanac for local times).
Magnitude -4.4 Venus presently lies in the constellation of Libra, moving into Scorpius on 9 January. The planet has a disc almost 25 arcseconds across and currently appears exactly half illuminated — just like a miniature first or last quarter Moon (depending on your telescope view). At this time, a telescope magnification of just 75× enlarges Venus to the same size as the Moon appears to the unaided eye.
Venus attains its greatest elongation of 46° 57′ 22″ west of the Sun at 04:54 UTC (4:54am GMT) on 6 January. As seen from the heart of the British Isles, the brightest planet presently rises in the east-southeast close to 4:30am GMT some four hours before the Sun. At 7am GMT on 6 January, Venus lies 0.675 astronomical units, or 100.9 million kilometres from Earth, which is about 260 times farther than the Moon.
All five of the bright naked-eye planets are observable in the pre-dawn sky from about the third week of January 2016, particularly if one lives south of the equator. But even from the UK, you can get to view the spectacle if you time it right — and the weather obliges! The last time that Mercury, Venus, Mars, Jupiter and Saturn appeared in the same sky was 11 years ago.
The first ten days of May offer observers in the British Isles their best opportunity to see Mercury in the early evening twilight during 2015. So, if you’ve never seen the innermost planet, let dazzling Venus be your convenient guide to this elusive little world.
The existence of a fifth giant gas planet at the time of the solar system’s formation — in addition to Jupiter, Saturn, Uranus and Neptune that we know of today — was first proposed in 2011. Now astrophysicists at the University of Toronto have found that a close encounter with Jupiter about four billion years ago may have resulted in the fifth giant planet’s ejection from the solar system altogether.
