Winter is well and truly upon us and the nights are long and dark. If we manage some clear skies, then this is a good time of year for observing.
There are some interesting this to look out for this month
Planets
Mercury
Mercury reaches superior conjunction on 21st January. It remains close to the Sun and is not really observable this month.
Venus
Venus reaches superior conjunction on the 6th January and is not observable this month
Mars
Mars finally reaches conjunction on the 9th January and is not observable this month, or for quite a few months yet.
Jupiter
Jupiter reaches opposition on the 10th January and is therefore observable throughout the night. It is a very prominent object in Gemini, just below the twin stars of Castor and Pollux. It is very well placed for observing and gets very high in the sky, meaning it avoids a lot of the atmospheric turbulence lower down. I recommend the website https://shallowsky.com/jupiter which shows you the position of the Galilean moons and the Great Red Spot at any time you pick. A few transits are as follows:
On the 6th, at 01.56UT, Io will transit Jupiter. As Jupiter is close to opposition, the Moon and its shadow will appear close together. It does this again on the 7th at 02:20UT. Ganymede transits on the 7th at 02:06UT and the shadow and moon are touching. If you’re up and it’s clear, this could be worth looking for. On the 10th at 07:11UT (opposition day) Calisto starts to transit in front of its shadow.
Saturn
Saturn is past its best now and will soon be moving into the twilight. Its magnitude is at +1 throughout the month, but the rings remain very nearly edge on throughout the month. Although still fairly low in the sky, it can be found in Aquarius, below the square of Pegasus. By mid-month, its coordinates are: RA 23h 49m, Dec -3o 34’. Note: As it’s a planet, it won’t twinkle like a star, making it easier to identify. You can use https://shallowsky.com to access the moons of Saturn as well.
Uranus
Uranus remains visible throughout this month. It lies in Taurus, a little below the Pleiades. Its coordinates: RA 03h 43m, Dec +19.5o, and magnitude +5.7.
Neptune
Neptune is still observable, as it is close to Saturn, being a little above it. It is not an easy object, but it can be found with coordinates: RA 0h 00m 21s, Dec -1o 25’. It is also below the square of Pegasus and has a magnitude of +7.9. By the end of the month it will become a more difficult object.
Moon Phases:
| 3rd Jan: Full Moon | 10th Jan: Last Quarter |
| 18th Jan: New Moon | 26th Jan: First Quarter |
The Lunar X and Lunar V shapes may be seen around 17.00UT on the 25th January. These shapes appear on the terminator, due to light catching crater rims, and are worth looking for. The X is south of the equator and the V to the north.
Occultations: On the evening of the 27th January from about 21:30UT, the gibbous Moon passes through the northern part of the Pleiades, occulting several stars. This could be a job for video.
Sun
The Sun is very low in the sky at this time of year, but still fairly active as it is still near solar maximum, so do watch out for large Sunspot groups. Remember to never look at the Sun directly without a proper solar filter.
Earth reaches perihelion around the 4th January and so is at its closest to the Sun. It won’t feel particularly warm though!
Aurora
Aurora may be visible this month as the northern skies are dark early. Watch out for any exceptional activity though, using one of the many aurora alert apps.
Meteors
The Quadrantid meteor shower occurs around the 3rd January. The Zenithal Hourly Rate (ZHR) at maximum may reach 80, but this year’s display will be rather spoiled by the full Moon. They are one of the richest showers of the year and well worth looking out for. There are many slow and bright meteors to be seen. As we will be approaching new Moon, these could be very favourable.
Deep Sky Objects
The Orion Nebula is well placed, as well as the Pleiades. To the east of Gemini (where Jupiter is) lies the sickle of Leo. Between these is Cancer. Look for the beautiful open cluster Praesepe M44, which is a lovely open cluster and a good target for astrophotography.
The Andromeda galaxy (M31) is very well placed, being almost overhead by mid evening. This also applies to the Double Cluster in Perseus. Both make great objects in binoculars or a small telescope and fantastic objects for astrophotography.
Neil Havard.
Any questions or for more information, contact Neil at coordassist@cotswoldas.org.uk
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