Sky notes for January 2018 Geoff Mitchell
The January night sky now sees some familiar winter constellations rising by early evening. The brighter planets are confined to pre dawn skies with Uranus and Neptune being the only telescopic planets in the early evening skies. The winter night sky contains many fine objects to view with both binocular and small telescopes.
There are two Full Moon during the calendar month, the second of which is therefore a `Blue Moon` (nothing to do with the colour). Both these occur when the Moon is nearest to Earth making the first a Perigee Moon i.e. slightly brighter and marginally larger in apparent size than normal. Total lunar Eclipse Jan 31st is alas not visible from UK.
The red planet Mars is also visible low in the south in pre-dawn skies, presenting a tiny telescopic image. Mars returns to opposition in July 2018. Jupiter now joins Mars in the Constellation of Libra making this low in our UK skies.
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.
The Quadrantids meteor shower reaches maxima in the afternoon of January 3rd. However unfavourable moonlight interferes with seeing these blue/ yellow meteors on evenings over the period January 1st to January 6th.
Planets in January 2018
Mercury is poorly placed low in dawn skies but is past greatest elongation (Jan 1st) and slips sunward by late Jan.
Venus is located in the daytime sky with superior conjunction on Jan 9th .
Earth reaches perihelion, its closest point in its orbit to the Sun on January 4th distance 147,100,176 km.
Mars is visible low in pre dawn skies, its apparent size just 5.3” by late January. (Poor)
Jupiter shines brightly in pre dawn skies with Mars at the end of the month
Saturn is poorly placed low in our dawn skies and will be visible in our evening skies by mid summer.
Uranus is visible early evening in the constellation of Pisces. (Binocular / Telescope required).
Neptune is located in Aquarius (Binocular / Telescope required). The constellation of Aquarius is positioned low in the west early evening
Moons phases in January 2018
New Moon Jan 17th Moonless, best time for deep sky observing.
First Quarter Jan 24th Best days to see shadow details in lunar craters (early evening)
Full Moon Jan 2nd/31st Best days to see bright ray craters like Copernicus / Tycho.
Last Quarter Jan 8th Moon visible in daytime skies. Do not look directly at the Sun.
Quadrantids range Jan 1st to Jan 6th, Max Jan 4th ZHR 80 / hour – unfavourable moonlight.
The highlights of the Month
Crescent Moon, Saturn and Mercury, low in East in dawn twilight 7am GMT
Milky Way visible high overhead on moonless evenings in darker skies.
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.
Crescent Moon visibility, Jan 17th 0.3% ultra thin crescent Moon sets 16:58 GMT within half a hour of sunset.
(Caution , always wait until the sun has completely set below the horizon before looking for crescent Moon )
Jan 18th a more favourable 2.3% crescent Moon with Earthshine visible after sunset m moon set 17:59 GMT
Comet 2016 R2 Panstarrs close to the Hyades star cluster in Taurus ( Moderate telescope required)
More detailed sky notes and LAS Newsletters, Finder charts are available to LAS members via the Members` page and details of planned Public open observing evening(s) please refer to LAS Website www.lutonastrolink.org.uk
Sky looking south 7 pm mid January 2018
LAS Finder chart for 2016 R2 Panstarrs and the Hyades star cluster ( early evening )
( reported 10th Magnitude (total) – Moderate (20cm) telescope or Imaging required)
Comet 2016 R2 Panstarrs is moving northward in the constellation of Taurus, passing in front of the Hyades star cluster – At the time of writing [Dec 28th 2017] the comet is reported as undergoing some fragmentation event
Refer to www.spaceweather.com
Sky looking east at 7pm mid January 2018
The constellations of Taurus, Auriga, Gemini and Orion can be seen rising early evening in January. The three stars Sirius, Procyon and Betelgeuse form the Winter Triangle asterism.
The Seven Sister’s cluster (M45, Pleiades) is an easily identified star cluster. Some people with keen eyesight may see up to 13 stars (how many stars can you see with unaided eye?), but a telescope will show over 400 faint stars in the cluster. Circle represents the approximate field of View (FOV) of a 10x 50 binocular / Finderscope.
Sky looking north at 7pm mid January 2018
The Plough stands on its handle follow the pointer’s Dubhe and Merek to find the polestar Polaris
The `W` shaped constellation of Cassiopeia looks more like a `M` and is on the opposite side of the polestar to the Plough.
Sky looking west at 7 pm mid January 2018