Weymouth Astronomy

The Planets - January 2021

Observing the planets can be extremely rewarding. Everyone remembers the first time they observed Saturn and it's rings or the gas giant Jupiter and it's Galillean Moons. Solar System


Mercury appears in the southwest after sunset around the 7th of the month shining at magnitude -0.6 and quickly rises into the evening sky. It reaches greatest elongation (east of the Sun) on the 23rd and will then have an elevations of 8 degrees 45 minutes after sunset.


Venus rises in the southeast over an hour before the Sun at the start of January but will be lost in the Sun's glare by the end of the month. It is heading towards superior conjunction on the 27th of March so will remain hidden from our view for some time.


We have just witnessed the best apparition of Mars for some years. As January begins, Mars at magnitude -0.2, and is just 1/10th as bright as at its peak last October. The red planet is easily viewed in the southern skies among the stars of Aries.


Jupiter, along with Saturn remains just visible as January begins low in the sky at at elevation of 5 degrees in the southwest when darkness falls at around 17:00 GMT and sets some 40 minutes later. Following their close conjunction on the 21st of December, they are still just 1.25 degrees apart on the 1st and remain within 2 degrees of each other until the 8th.


Saturn just precedes Jupiter into the sky, some 1.25 degrees ahead at the start of the month and as with Jupiter, can be seen very low in the southwest (among the stars of Capricornus) as January begins but will soon be lost in the Sun's glare.

Information collated from Jodrell Bank and Astronomy Now magazine