As nautical twilight starts at 7am GMT for the centre of the British Isles on 9 January, planets Venus and Saturn are separated by just 9¼ arcminutes — less than a third of the apparent diameter of the full Moon — very low to the southeast. They were at their closest (5 arcminutes) at 4am GMT, but below the UK horizon at that time. Both planets lie 6⅔ degrees to the upper left of star Antares, so all three will fit within the field of view of a 7×50 binocular. AN graphic by Ade Ashford.On Saturday, 9 January at 3:57am GMT, magnitude -4.0 Venus passes just 5 arcminutes — less than one tenth of a degree — north of magnitude +0.5 Saturn. While the instant of closest approach will be missed by observers in the extreme west of Europe as Venus and Saturn will still be below the horizon, by 7am GMT the ‘double-planet’ will be high enough to be glimpsed with the naked eye very low to the southeast from the UK.
By 7am GMT the gap between these two prominent planets will have widened to 9¼ arcminutes — still less than a third of the apparent diameter of the full Moon. Observers with motorised equatorial or GoTo mounts can track the rising pair in the same eyepiece field at magnifications up to 175x until Saturn fades into daylight.
As always, whenever observing in daylight please take extreme care lest the Sun enters the field of view of your telescope or finder with disastrous consequences for your eyesight or anyone else who accidentally looks at it.
In the early evening of Tuesday, 23 February, the rising waning gibbous Moon — one day after full Moon — lies just 3½ degrees from magnitude -2.5 planet Jupiter low in the eastern sky. Jupiter is closest to Earth on Tuesday, 8 March, so now is the time to get acquainted with the solar system’s largest planet.
Observers in the UK with clear skies around 1am BST on Tuesday, 21 May can see Jupiter, the solar system’s largest planet, just 4 degrees from the waning gibbous Moon low in the south-southeast. At this time both the Moon and Jupiter fit within the same field of view of binoculars magnifying less than 10×, while telescope users can also view Jupiter’s Great Red Spot.
Mercury attains its maximum westerly elongation from the Sun on 26 August, meaning that the innermost planet is currently well placed for observation from the UK and Western Europe in the eastern sky around 40 minutes before sunrise. In addition to those in the evening sky, you might just see all five bright naked-eye planets this month!
