Northants Skies - January 2021

New Moon On 13th January

Full Moon On 28th January



Mercury begins the new year lost in the evening twilight following it’s superior conjunction passage back on 20th December.  On the 14th January, look very low above the south-western horizon at around 4.45pm and see if you can spot a very thin waxing crescent Moon to the left of a magnitude 0 Mercury.  It will be a challenging observation, however if you have an unobstructed south-western horizon it is worth a go.  If you wish to use binoculars to pick up both objects, then it may make the spot a bit easier, but be sure that the Sun has set before starting your ‘sweep’.
Following it’s lunar conjunction, the innermost planet does appear a bit higher above the south-western evening horizon after sunset, reaching greatest eastern elongation on 24th January when it will shine at magnitude -1 and be around five degrees above the horizon at 4.45pm.
Mercury quickly draws back towards the twilight by month end, fading as it does so.


Venus begins the month very low above the south-eastern pre-dawn horizon, although it is still stunningly bright at magnitude -4.  Our neighbouring planet is however reaching the end of it’s morning apparition and has disappeared from view by mid-month.  On the morning of 11th January, watch from around 7.15am as Venus will rise with the thin waxing crescent Moon to it’s right.


Mars is now the bright naked eye planet on view in the evening sky, it’s distinctive reddish tinge being visible high in the south as evening twilight fades.  The red planet is however now well past it’s observing best for it’s current apparition, shining at magnitude 0 at mid month.  The first quarter Moon lies to the lower right of Mars on the evening of 20th January and on the following evening to the lower left.  Through a telescope, the disc size of Mars shrinks from 10 arc seconds across at the start of January down to 8 arc seconds by the end of the month.  Telescopes in the range of 6-inches and above should still be able to resolve some major martian surface features, however it becoming more and more tricker.  Mars catches up with the more distant world of Uranus during January (further details in the Uranus section).


Jupiter may just be glimpsed for the very first few days of 2021, very low above the south-western horizon as evening twilight fades.  The giant planet is at the end of it’s apparition and quickly disappears from view entirely.  It passes through solar conjunction on 29th January.


Saturn is in the same part of sky as Jupiter,however being over two magnitudes fainter is not going to spotted in the evening twilight  unlike it’s larger cousin.  Saturn passes through solar conjunction on 24th January


Uranus lies among the stars of Aries and is an easy spot with a pair of binoculars.  Still visible at a good altitude for most of the evening hours, this icy giant spends some of the month in close proximity to Mars.  Uranus and Mars appear at their closest on the evening of 21st January, the sixth magnitude small greenish disc of Uranus appearing below Mars on that evening.  The two planets are in close proximity for most of the month though, appearing in the same small binocular field of view from around the 10th January almost through until month end.So if you’ve never spotted Uranus before, why not use Mars as your signpost and ‘bag’ this distant world.


Neptune remains amongst the stars of Aquarius, low down in the south-west as evening twilight fades.  At magnitude 8, the planet sets just after 9pm mid-January, so ideally should be sought out as soon as it’s dark enough in the early evening.


The Quadrantid Meteors reach their annual short, but sharp, maximum on the night of 3rd/4th January.  Named after the long defunct constellation of Quadrans Muralis, the radiant of the meteor shower lies in the very northern part of Bootes. The radiant of the meteor shower remains low in the north throughout the evening hours, rising in the north-east after mid-night, meaning that observing after this time is likely to be most productive.  Unfortunately strong moonlight is going to be present at this time, which will ‘drown out’ some of the fainter members of this meteor shower, from which we could normally expect a Zenithal Hourly Rate of around 120 meteors.  The Quadrantid peak is only spread over a few hours, so outside of the night of 3rd/4th January little will be seen.