Sky Notes January 2016

Sky Notes for January 2016                Geoff Mitchell

The January night sky now sees some familiar winter constellations and the bright planet Jupiter rising by late evening. The winter night sky contains many fine objects to view with both binocular and small telescopes. Comet Catalina (C/2013 US10), visible in binoculars or small telescope heads northward during January and is closest to Earth (109 million km) and is positioned close to the handle of the Plough asterism around mid month. (See notes)

The constellations of Cygnus and Lyra can be seen slipping into the west early evening; these are noted for the bright stars of Deneb and Vega which appear low in the north by late evening , both stars are circumpolar , i.e. are above the horizon from UK latitude .

The Milky Way stretches from the constellation of Auriga , marked by the bright star Capella in the east up into Perseus and through the `W` shaped constellation of Cassiopeia high overhead and down along the cross shaped constellation of Cygnus low in the west . This faint band of stars best seen on dark moonless evenings.

Auriga has the bright star Capella, which is circumpolar from UK latitudes and so is always visible. The constellation of Auriga contains some nice star fields and star clusters visible in binoculars.

In the south west the constellation of Pegasus, noted for its `Square ` shape and the adjacent constellation of Andromeda noted for The Andromeda Galaxy (M31) , visible to the unaided eye as a faint fuzzy patch on moonless evening can now be seen mid evening . The Square of Pegasus is a useful sign post constellation and also is a good test for sky conditions, (how many faint stars you see within the square is indicates just how good your seeing conditions are). Follow the two end stars (Scheat and Markab) down to find the star.

In the north Ursa Major, The Plough or The Great Bear is seen low with its handle or tail parallel to the horizon mid evening. Use the right hand pair of stars Dubhe and Merak (The pointers) to find the faint pole star Polaris and hence the position of North.

Look to the east early evening to see the seven sisters’ (Pleiades, M45) star cluster and constellation Taurus .The Hyades star cluster makes the characteristic `V` shaped asterism in the constellation of Taurus and is noted for the bright, red foreground star Aldebaren in Arabic Al Dabaran is `The follower ` of the Pleiades across the skies `, in old English known as Oculus Tauri, `the eye of the bull`. Also in Taurus is the famous `Crab Nebula` M1, the first object catalogued by French astronomer Charles Messier, it is a remnant from a supernova explosion witnessed by Chinese observers in AD1054. Telescopically it looks like a grey oval shaped nebula, but larger instruments show some detail ie extensions that give it its name, looking like the claw of a crab. At the centre of the Crab Nebula is a rapidly rotating pulsar star, the remains of the supernova, surrounded by the expanding shell of gas that is the Crab Nebula.

By mid evening the familiar winter constellations of Orion (The Hunter) is rising with bright red star Betelgeuse (top left) , white star Rigel (bottom right ) and the three stars of Orion’s belt Mintaka , Alnilam and Alnitak . Below Orion’s belt can be seen the misty patch that is M42 / M43, visible to the unaided eye, it is one of the gem’s of the winter skies when seen with a telescope. This nebula some 30 light years across is illuminated by a group of four hot young stars that is known as the `Trapezium `asterism, visible under moderate magnification.

Jupiter rises in the constellation of Leo (The Lion) and will feature more in the spring skies. Small telescopes show the four bright moons discovered by Galileo in 1610 and the famous cloud belts. The Great Red Spot is currently more subtle and straw coloured. Jupiter’s Galilean moons show shadow transits and go into eclipse behind the planet. A 21cm aperture or larger telescope is recommended to see the tiny dark shadow disks of the three Galilean moons cast onto the cloud tops of Jupiter turbulent atmosphere.

Planets in January 2016

Mercury is low at dusk early Jan. Inferior conjunction Jan 14th , returns to dawn skies late Jan / Feb
Venus rises at least 2 hours before the Sun, visible low in dawn twilight in constellation of Ophiuchus. Earth reaches perihelion, its closest point in its orbit to the Sun on January 2 nd distance 147,100,176 km.
Mars is an early morning object, conjunction with the Moon Jan 3rd in the constellation of Virgo low in UK skies
Jupiter shines brightly in the east on the border of Leo / Virgo late evening by mid January.
Saturn is positioned low in dawn skies in January and moves into the constellation of Ophiuchus.
Uranus is visible early evening in the constellation of Pisces. (Binocular / Telescope required).
Neptune in Aquarius (Binocular / Telescope required). The constellation of Aquarius is positioned low in the west but slips into twilight skies by early evening heading towards conjunction late February in our daytime skies.

Moons phases in January 2016

New Moon Jan 10th Moonless, best time for deep sky observing.
First Quarter Jan 16th Best days to see shadow details in lunar craters (early evening)
Full Moon Jan 24th Best days to see bright ray craters like Copernicus / Tycho.
Last Quarter Jan 2nd Moon visible in daytime skies. Do not look directly at the Sun.

Meteor showers: Quadrantids range Jan 1st to Jan 6th, Max Jan 4th ZHR 80 / hour – quite favourable.

The highlights of the month

Venus and Saturn in dawn twilight skies, very close conjunction Jan 9 th , separation just 6.5 arc min

Milky Way visible high overhead on moonless evenings in darker skies.

Jupiter returns to our late evening skies, conjunction with the Moon Jan 27th

M31 the Andromeda Galaxy is visible on moonless evenings, best seen in binoculars.

Double cluster, on the Perseus /Cassiopeia border, nice pair of star clusters.

Pleiades (Seven Sister’s) star cluster (M45) rising in the east best seen with binoculars.

Orion Nebula (M42) is a beautiful sight seen telescopically.

Beehive cluster (M44) visible to the unaided eye but best seen with binoculars.

Comet C/2013 US10 is visible in binoculars, best seen in moonless late evenings mid January (see notes).

Moon `occults` stars of the Hyades cluster on Jan 19th / 20th

More detailed sky notes and LAS Newsletters, Finder charts are available to LAS members via the Members` page on the LAS Website