CDAA

Written by David Pugh

Mercury, the inner-most planet, is a bright pre-dawn object for the first few days of the year, seen low over the SE horizon. Dazzling Venus (mag -4.5) reaches greatest elongation from the Sun on Jan 10, offering an improving showing in the SW after sunset. On Jan 3 around 5.30pm a young crescent Moon lies only 2 degrees below Venus making for a beautify view. Then around 5.45pm on Jan 18 there is a conjunction of Venus and Saturn when they will lie just over 2 degrees apart and 23 degrees high in the SW. Mars, the red planet, (mag -1.4), is now a brilliant object observable virtually all night. It reaches its long awaited opposition on Jan 16 riding high in Gemini and this will be its best observing period for 2 years. As an aphelic (furthest from the Sun) opposition it means that Mars only reaches 14.5" in diameter but a 100mm scope will still give a good view of the planet. Red and orange filters can be helpful in spotting surface features. On 13/14 Jan the full Moon closes in on Mars from the west, the pair lying under a degree apart at about 4am.

Jupiter, king of the planets, (mag -2.7), is a brilliant object riding high (60 degrees elevation) among the bright stars of Taurus and dominates the southern evening sky all month. Even a pair of binoculars shows its globe and its 4 galilean moons, often in a line. A telescope shows much more detail including its equatorial belts and the famous but shrinking Great Red Spot plus, occasionally, the transit of one of its moons across its surface. Well worth keeping an eye on.

Saturn, the lovely ringed planet, (mag +1.1), still lies in Aquarius but is now sinking down in the SW so you need to catch it early evening. Apart from the conjunction with Venus, (mentioned above), Saturn is occulted by the Crescent Moon on Jan 4th. From London Saturn is hidden from 5.21 to 6.31pm. (Clacton is 4 minutes ahead of London). This event occurs over 25 degrees above the SSW horizon. If it is clear don't miss it!

The ice giant Uranus (mag +5.7) is very well placed in Aries. So it is on view all night offering a very good observing opportunity. It can be observed with binoculars but you will need a telescope to resolve its small greenish disc. Neptune (mag +7.9) is an early evening object in Aquarius observable for an hour or so. You will need a small to medium sized telescope to resolve its small bluish disc but you can spot this bluish "star" with binoculars if you know where to look.

The Quadrantids meteor shower, radiating from east of the tail of the Plough) reaches a peak around 03.00UT on Jan 3rd. It is a strong meteor shower favourable this year as the Moon will not interfere. However, the best display will be after midnight with rates typically of 50 to 60 meteors per hour but with a narrow peak of 4 to 6 hours.

There has been some mention in the news concerning the possible imminent outburst of the recurrent nova T Coronae Borealis currently at mag 10. If it does outburst in the next few weeks, unfortunately it would be an early morning object in the NE sky. It last outburst in 1946 reaching mag 3.0 and mag 2.0 in 1866 when it was discovered. It is nicknamed the "Blaze Star"

All of the deep sky objects and constellations mentioned in the last two months are still well placed for observing but need to be observed early evening. This month, as there is a lot happening in the Solar System, I will cover just one winter constellation. However, it is the most famous - Orion the Hunter. Orion culminates due south at 22.30 at the start of the month and 20.30UT by Jan 15 but will be on view all night. Orion is easily recognised by the line of three mag 2 stars forming Orion's "Belt" - Alnitak, Alnilam and Mintaka, all blue giant stars. At Orion's right "shoulder", (left as we view it), lies the famous red supergiant variable star Betelgeuse which varies in brightness irregularly between mag 0.3 and 1.1. However, two years ago it faded to mag 1.5 after puffing out some of its outer layers in our direction. But Betelgeuse is not the brightest star in Orion. Rigel, marking Orion's left foot hold this title. It is a super luminous blue supergiant star of mag 0.14 lying 860 lys away with a luminosity 120,000 times that of the Sun!

The left hand stat Alnitak in Orion's belt illuminates the adjacent Flame Nebula NGC 2024, a bright emission nebula. However, to stand any chance of seeing this through a telescope one needs to exclude the glare of Alnitak from the field of view. It is best as a photographic object and this especially applies to the finest example of a dark nebula Barnard 33 the famous Horsehead Nebula lying just to the south of Alnitak. Then, immediately below the centre of Orion's Belt hangs the "sword" of Orion. What appears to the naked eye to be a vertical line of 3 faint stars with the naked eye transforms, even with binoculars, into a number of faint stars with the middle "star" appearing as a nebulous cloud. This is the famous Orion Nebula (M42 and 43) which, for telescope users, is arguably the most popular deep sky object in the whole sky. Located 1,350 lys away this bright emission nebula is the nearest large stellar nursery where new stars are being formed. It is being illuminated by the bright young stars of the Trapezium cluster at the centre of the nebula. A must see object!

Returning to Alnitak and heading north from it we find the fainter nebula M78, a blue reflection nebula which is quite a challenge visually. Finally, on this tour of Orion we head up toward the N. border of Orion with Gemini to find NGC 2174 the Monkey Head Nebula, so called due to the appearance of this emission nebula in photographs.

Good Hunting and I hope to see you tomorrow evening at the society's monthly meeting.

Best Regards

David