Posted by on Dec 30, 2018 in Main |

The New Year begins with a cornucopia of celestial sights, from colourful shooting stars to a glorious Morning star and an eclipse of the supermoon. A bevy of brilliant stars, Bettlegeuse and Rigel in Orion. Aldebaran, the bright red eye of Taurus. Capella crowning Auriga. Caster and Pollux, the celestial twins in Gemini, and glorious Sirius in Canis Major. On the night of the 20th to 21st of January in the early hours we are treated to the most stunning eclipse to be seen in the north of England this year, as a supermoon is engulfed by the Earth’s shadow.

As for the star patterns, what a great month to see them. Look north-west and the first group you will notice will be Ursa Major, or the Plough, with its tail pointing towards the Horizon. The ‘W’ shape of Cassiopeia is high up in the north-west. The North Star, of course, will be in its usual position due north. It cannot be anywhere else.

The southern part of the night sky is dominated by Orion, which cannot be overlooked. Led by Betelgeuse and Rigel. All of the winter constellations can now be seen. If you use the three stars of Orion’s belt and draw a line to the left it will point to Sirius the Dog Star, the brightest star in the sky.

You will find to the right of Orion, Aldebaran, the bright red eye of the Taurus the bull. Above Orion you will see Capella, crowning the constellation Auriga, and nearby Castor and Pollux, the celestial twins in Gemini.

You will have to be up before dawn to catch any naked eye planets this month, and they are putting on quite a performance.

Jupiter starts the month rising around 5 a.m., and brightens from magnitude -1.9 to -1.9 as the month progresses whilst its angular size increases slightly from 31.8 to 33.6 arc seconds.

Saturn passes behind the Sun on the 2nd of the month so will not be visible in the pre-dawn eastern sky until around the third week of the month shining with a magnitude of +0.6. With a disk of ~15 arc seconds across and with rings spanning over twice this, it will rise some one and a half hours before the Sun by month’s end.

Mercury might just be glimpsed very low in the southeast just before sunrise shining at magnitude -0.4 in the first few days of the month. Binoculars could well be needed to reduce the background glare, but remember do not use them after the Sun has risen.

Venus reaches greatest elongation west some 47 degrees away from the Sun on January 6th so dominates the eastern sky rising some 3 hours before the Sun. It begins January with a dazzling magnitude of -4.6. Its angular size reduces from 26.3 to 19.4 arc seconds during the month as it moves away from the Earth but at the same time, the percentage illuminated disk (its phase) increases from 47% to 62% – which is why the brightness only reduces from -4.6 to -4.3 magnitudes. See the highlight above when it lies close to Jupiter.

The only prominent planet in the evening sky is Mars. Though fading from +0.5 to +0.9 magnitudes during the month, remains prominent in the southern sky after sunset at an elevation of ~36 degrees, increasing to 41 degrees during January as it moves north-eastwards across the constellation of Pisces. (If only it could have been at this elevation when at closest approach last year!) Its angular size falls from 7.5 arc seconds to 6 arc seconds during the month so one will not be able to spot any details on its salmon-pink surface.

The first regular meteor shower of the year is the Quadrantids, which can be seen on the night of January 3/4. This year there will be no bright moonlight to spoil the show. They could be the best display of shooting stars this year. The Quadrantids is the only meteor shower that takes its name from a defunct constellation. It is named after the Mural Quadrant, one of many which no longer exists because the star map has been redrawn.

Other high lights of the month will be: –

3rd January – Looking southeast before dawn one should, if clear, be able to easily spot Jupiter lying below a very thin crescent Moon. The red giant star, Antares is down to the right of Jupiter.

12th January – Looking south in the evening if clear, Mars will be seen lying above a waxing crescent Moon.

21st January – If clear in the hours before dawn, we should be able to see a Total Eclipse of the Moon as it moves through the Earth’s shadow at times indicated on the chart.

31st January – If clear just before dawn, and given a low horizon towards the southeast, one should be able to see a thin waning crescent Moon lying between Jupiter (on its right) and Venus shining brightly to its left. Antares is down to the lower left. A nice photo opportunity.

Phases of the moon for January are :-

New Moon 6th

First Quarter 14th

Full Moon 21st

Last quarter 27th