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Society News

Programme of Events for January 2010 All meetings are held at Bristol Grammar School. 8th Jan Observatory Maintenance & Observing (if clear) 15th Jan Shadows of the Big Bang: The Cosmic Microwave Background Radiation - Katy Lancaster 22nd Jan Club Night - Simon Smith Back to Basics - 29th Jan Cosmic Al-Chemical Furnaces - Dr Roger Moses

Welcome to the start of another year, our programme of speakers resumes with Katy Lancaster from Bristol University. Later in the year we have the return of some of our regular guests like Prof. Mark Birkinshaw and Andy Lound. Some of our other speakers will be familiar to a lot of our members, Prof. Andrew Coates, Bob Mizon, Guy Hurst and Haley Gomez have all given talks to the society in recent years. Our other guest speakers this year are Chris Lintott, Prof. Mark Simms and Konrad Malin-Smith. Solar Observing We are hoping to restart the solar observing sessions at Tyntesfield later in the year, these were very popular with the visitors to the National Trust property. If you would like to help at one of these sessions please contact Allan McCarthy who organises the events. AGM This year’s AGM will be held on February 12th. At the AGM the entire committee stand down, and all fully paid up members are eligible to stand for election to the committee. There are also two positions for Junior members (under 18). If you think you have something to offer the society please get someone to nominate you for one of the positions.

Don’t forget to check out the BAS website where you can get all the latest info about the society. http://www.bristolastrosoc.org.uk/

Bristol Astronomical Society are a Registered Charity, No. 299649

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Bristol Astronomical Society Information Leaflet January 2010

Constellation of Auriga

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Welcome to the start of another year, lets hope that this one is better than last year, when we saw some of the worst weather for many years. So what do we have to look forward to during the year? Eclipses There will be four eclipses during the year two of the Sun and two of the Moon unfortunately none of these are visible from the UK except the start of the total eclipse of the Moon in December. Annular Eclipse of the Sun on Jan 15th will be visible from central Africa, south-ern India, northern Sri Lanka, Burma and China. A total eclipse of the Sun on July 11th will be visible from a few of the French Polynesian islands, Easter Island, the southern tip of Chile and cruise ships in the Pacific Ocean. The partial eclipse of the Moon on June 26th will be visible from the Pacific Ocean, New Zealand and Parts of Australia. The total eclipse of the Moon on December 21st will be visible from Canada, the USA, Central America and the northern part of South America. From the south of the UK the initial stages of the eclipse will be visible with the Moon very low in the south-western sky. Equinoxes & Solstices The Vernal (Spring) Equinox occurs on March 20th. The Autumnal Equinox occurs on September 23rd The Summer Solstice occurs on June 21st (longest day) The Winter Solstice occurs on December 21st (shortest day) Planets Mercury Mercury will be at inferior conjunction on January 4th, April 28th, September 3rd and December 20th. It will be at Superior conjunction on March 14th, June 28th and October 17th. Mercury will be at greatest western elongation on January 27th, May 26th and September 19th. It will be at greatest eastern elongation on April 8th, August 7th and December 1st. The best time to catch a glimpse of the elusive innermost planet this year is April for an evening apparition and September for a morning apparition. Venus

The Year Ahead

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Epsilon (ε) Aurigae is the most northerly of the triangle of stars known as ‘the kids’ it is an eclipsing binary with a magnitude range from +2.92 to +3.83, and a period of a little over 27 years. Minima lasts for about a year, the next one is due in 2011. Epsilon has the proper name Almaaz which comes from the Arabic mean-ing ‘He Goat’. The star was not originally one of the ’Kids’, as its Arabic name implies it was male counterpart of Capella (the She Goat). Zeta (ζ) Aurigae, known as Haedus 1; is the easternmost of ‘the kids’, it is another eclipsing binary, the components are a K-class (K4) orange super giant and a blue B-class (B5) star. The two stars orbit each other every 972 days. As the orbital plain lies along our line of sight an eclipse occurs every orbit when the smaller but brighter B class star is completely hidden behind the larger, cooler K-class star. Zeta varies in brightness between +3.61 to +3.99. The third of ‘the kids’ eta (η) Aurigae, Haedus II is a hot B-class (B3) dwarf star. Eta is a member of the Cassiopeia-Taurus association of hot class O and B stars, an extended group that stretches across over 100 degrees of sky from Taurus to Orion. The members of this group were born more or less at the same time and are now separating in all directions. Iota (ι) Aurigae has the proper name Hassaleh. Iota lies to the south of the ‘kids’ and is a K-class (K3), orange giant, nearing the end of it’s life. Iota is so large that its diameter has been directly measured at over 106 times the diameter of the Sun. AE Aurigae is a ‘runaway star’ which seems to have been ejected from the star forming region in Orion around 2.7 million years ago. The star is one of a group known as the Orion OB Association. AE Aurigae is a variable star which ranges in brightness between +5.4 and +6.1.

Constellation of the Month

Objects in Auriga

Object NGC Type Mag RA Dec M36 1960 Open Cluster +6.0 05h 36m +34° 08'

M37 2099 Open Cluster +6.4 05h 52m +32° 33'

M38 1912 Open Cluster +5.6 05h 28m +35° 50'

Epsilon Aur Eclipsing binary +3.0 to +3.9 05h 01m +43° 49'

1931 Emission Nebula +11.3 05h 31m +35° 15'

1907 Open Cluster +8.2 05h 28m +35° 19'

AE Aur Variable Star +5.4 to +6.1 04h 56m +33° 09'

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Venus will be at superior conjunction on January 11th, inferior conjunction on October 20th. It will be at greatest eastern elongation on August 20th, greatest western elongation occurs on January 8th 2011. Venus will be at it’s brightest on December 4th when it will be a dazzling –4.7. Earth Earth is at Perihelion (closest point to the Sun) on January 3rd and Aphelion on July 6th. Mars Mars reaches opposition on January 29th when it will be in the constellation of Cancer , this is two days after it’s closest approach to the Earth when it will be at a distance of 99.3 million km. On March 31st the red planet will reach Aphelion (furthest point from the Sun). Jupiter Jupiter is in conjunction with the Sun on February 28th, and reaches opposition on September 21st. Saturn Saturn comes to opposition on March 22nd and is at solar conjunction on October 1st. Uranus Uranus is in conjunction with the Sun on March 17th and reaches on September 22nd. Neptune Neptune is in conjunction with the Sun on February 14th and reaches opposition on August 20th. Comets There are a number of short period comets that reach perihelion this year and may be visible in medium sized instruments. Comet 81P/Wild in February should reach magnitude +9, 2P/Encke magnitude +7 in August and 103P/Hartley may be as bright as magnitude +4 in October. We can always hope for a spectacular comet to appear from the depths of space to round off a promising year.

The Year Ahead

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The Sun The Sun & Moon Sun and Moon Rise and Set times for January 2010

Sun Moon Rise Set Rise Set

01 08:16 16:12 17:15 08:51 02 08:16 16:13 18:46 09:23 03 08:15 16:14 20:15 09:47 04 08:15 16:16 21:42 10:06 05 08:15 16:17 23:05 10:23 06 08:15 16:18 10:40 07 08:14 16:19 00:25 10:57 08 08:14 16:21 01:45 11:17 09 08:13 16:22 03:02 11:40 10 08:13 16:23 04:17 12:10 11 08:12 16:25 05:25 12:49 12 08:11 16:26 06:23 13:38 13 08:11 16:28 07:11 14:37 14 08:10 16:29 07:47 15:43 15 08:09 16:31 08:15 16:52 16 08:08 16:32 08:36 18:01 17 08:07 16:34 08:54 19:10 18 08:06 16:36 09:08 20:19 19 08:05 16:37 09:22 21:27 20 08:04 16:39 09:35 22:36 21 08:03 16:40 09:49 23:46 22 08:02 16:42 10:05 23 08:01 16:44 10:24 00:59 24 08:00 16:46 10:49 02:15 25 07:59 16:47 11:24 03:32 26 07:57 16:49 12:12 04:46 27 07:56 16:51 13:17 05:50 28 07:55 16:53 14:37 06:40 29 07:53 16:54 16:07 07:18 30 07:52 16:56 17:40 07:46 31 07:50 16:58 19:10 08:08

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The third of the clusters, M38 is the northernmost of the three, lying around 2 degrees northwest of M36. The cluster has about 100 members grouped within an area of around 15 arcminutes. Towards the centre of M38 the brightest dozen or so stars form an obvious cross shape.

Around 30 arcminutes to the south-southwest lies the open cluster NGC 1907. The cluster contains around 30 stars within an area of 7 arcminutes. At magnitude +8.2 it should be visible in small telescopes. NGC 1931 is an emission nebula which lies just to the southwest of

M36. It resembles small version of the Orion Nebula. At magnitude +11.3 and with an apparent diameter of 3 arcminutes you will need a large telescope to observe this object. Stars in Auriga The six brightest stars in Auriga form an irregular pentagon shape. Shining at magnitude +0.08, Capella, alpha (α) Aur, the brightest star in the constellation and ranks as sixth brightest in the sky. To the naked eye Capella appears to be a normal G-class yellow star, however it is in fact a multiple star system. The two main components are both G-class (G8 and G0) giant stars. The pair orbit each other every 104 days but are too close to each other to be split by Earth based telescopes. In 2001 the Hubble Space Telescope managed to split the pair using the Faint Object Camera (FOC). Each of the stars has a diameter at least ten times that of our Sun. The two components are roughly the same temperature as our Sun, around 6000 K. There is a third, fainter companion that is itself a double, comprising of a pair of red M-class dwarfs. Beta (β) Aurigae which lies at the northeast corner of the pentagon has the proper name Menkalinan, from an Arabic phrase meaning ‘the shoulder of the rein-holder’. This is another multiple star, comprising of two A-class stars in a very close orbit, less than the distance between the Sun and Mercury, which means we are unable to split the stars. We know that the star is a double due to the fact that every 3.96 days the brightness drops by about 1/10 of a magnitude. A third com-ponent, a very faint red dwarf, orbits the pair at a distance of around 330 AU. Theta (θ) Aurigae lies to the south of beta, this is a binary star, the primary is an A-class (A0), magnitude +2.6, blue-white star, its companion is a magnitude +7.1 G-class (G2) yellow dwarf similar to our Sun. The pair are separated by 3.6 arcseconds.

Constellation of the Month

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Auriga Abbreviation: Aur: Genitive: Aurigae Mythology Auriga is one of the 48 classical constellations handed down to us in Ptolemy's Almagest. There are a number of legends surround the constellation, in one of the most popular Auriga represents Erichthonius, a King of Athens and the son of Vulcan and Minerva. He was deformed and his difficulty in walking led him to invent the four horse chariot and earned him a place in the heavens. In another, Auriga represents the son of Mercury who trained chariot horses which were famous for being the fastest in the world. Auriga’s brightest star, Capella, also has a legend linked to it. Cappella is thought to represent the goat that suckled the young Jupiter. At some point Jupiter broke off one of the goat’s horns and to make amends he imbued the horn with magic so that it would be filled with whatever the possessor wished for. It was given the name Cornucopia, or "horn of plenty." The constellation first appeared in star charts by Eudoxus around the 4th century BC. Objects in Auriga There are a number of star clusters that lie within Auriga’s boundaries. The most prominent and well known are the three Messier objects M36, M37 and M38, all of which can be seen as hazy patches in binoculars. There are also plenty NGC objects in Auriga, however some of the these can be difficult to pick out from the rich background of the Milky Way. The first of the Messier objects is M36, this is a fairly compact cluster of around 60 stars grouped win an area of approximately 12 arcminutes. M36 has an a integrated magnitude of +6.0. The brightest members of the cluster are between magnitude +9 and +11. M36 is a relatively young cluster, none of it’s members have yet reached the red giant stage of their lives. The second of the Messier objects, M37, is the brightest of the trio with an overall

magnitude of +5.6. This is also the richest of the clusters with around 150 members packed in an area of 20 arcminutes. M37 lies just outside the pentagon shape formed by the brighter stars of the constellation. Through a telescope this is one of the finest open clusters in the sky, appearing roughly triangular in shape

with a bright blue star at it centre.

Constellation of the Month

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The Sun Towards the end of last year there was a increase in activity on the Sun and we were fortunate to have a Sun spot visible for our last public solar observing event at the National Trust’s Tyntesfield Estate. During December there were a number of active regions (AR) visible on the Sun along with plenty of prominences for those with access to an H alpha telescope. Lets hope that the predictions that Solar Cycle 24 will be a quiet one are wrong and we get plenty of activity to see and to show the public at all of our events in the coming year. There is an annular eclipse of the Sun on January 15th, unfortunately this will not be visible from the UK. Annularity begins at 05:14 UT and ends at 08:59 UT. Maximum duration of the Annular phase will be 11minutes 8 seconds occurs in the Indian ocean. The reason the maximum phase is so long is because the Moon is close to Apogee (furthest point from Earth) at the time of the eclipse and appears much smaller that the Sun so takes longer to cross the disc. The Moon

The Moon is at Perigee (closest point to Earth) on January 1st (358,680 km) and January 30th (356,590 km) and at Apogee (furthest point) on January 17th (406,430 km). This months featured object was recently the subject of the Astronomy Picture Of the Day at http://antwrp.gsfc.nasa.gov/apod/astropix.html The 3D image of this unusual pair of craters was superb. The craters in question, Messier and Messier A, lie on the Mare Fecunditatis (Sea of Fertility) at Lon 47.6° East, Lat 1.9° South. The crater was named by Johann Heinrich von Mädler in 1837 to honour Charles Messier, who was known as the ‘Ferret of Comets’. Messier discovered 16 comets during his life, although nowadays he is more famous for his

The Sun & Moon

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23rd 10:53

30th 06:17

7th 10:40

Messier Messier A

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list of deep-sky objects which he compiled so other observers would not confuse them with comets. It is thought that he chose this crater because of the bright rays of ejected material running west from the crater for 120km across the Mare, giving he appearance of a comet with a tail. However the rays seem to come from Messier A which was previously known as Pickering until the IAU changed it in 1964 to Messier A. The Moon by Wilkins and Moore clearly shows it as Pickering W.H. Messier is defiantly oval in shape meas-uring about 15km by 9km (9 by 5 miles) and about 1,250m deep with high walls. The longer dimension is oriented in an east-west direction. The interior of the crater is brighter than the surrounding mare making it easy to locate. Messier A lies 20km to the west, it is a double crater, the larger of the two craters is younger than the smaller one. Messier A measures 13km by 11km (8 by 7

miles), the longer dimension is oriented north-south, at right angles to Messier, indicating that the craters were not formed at the same time. You will need a telescope to see these small craters but do take a look as they are quite a remarkable sight. The best time to observe these two craters is 3 days after Full Moon (January 3rd) or 4 days after New Moon (January 19th) As the terminator crosses the craters. To see the comet effect you will have to wait until the terminator has completely crossed the Mare Fecunditatis and it is in full sunlight.

The Sun & Moon

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Mercury passes through inferior conjunction on the 4th, then swiftly moves west of the Sun reaching greatest western elongation on January 27th when it will be 25° from the Sun. The planet is not well placed for observers in the UK as it will be very low in the south-eastern sky for a short time before sunrise.

Venus passes through superior conjunction on January 11th and is therefore not visible this month.

Mars rises in the early evening and is visible throughout the hours of dark-ness. The red planet begins the month in Leo and it’s retrograde motion takes it across the border into Cancer on the 9th. Mars reaches its closest point to the Earth on the 27th when it will be just 99.3 million km away. The planet reaches opposition on the 29th at 19:31 in the constellation Cancer. At the time of opposition Mars will have an apparent diameter of 14.1 arcseconds and will shine at magnitude

The Planets

Date RA Dec Mag Phase Dia Rise Set 01/02 09h 28m +18° 53'' -0.8 96% 13" 19:04 10:36 15/16 09h16 m +20° 20'' -1.1 99% 14" 17:51 09:43 29/30 08h 53m +22° 12'' -1.3 100% 14" 16:16 08:34

Mars Transit 02:50 01:47 00:25

Date RA Dec Mag Phase Dia Rise Set 01 18:36h m -23° 37'' -3.9 100% 9.8" 08:11 15:55 15 19h 52m -21° 52'' -3.9 100% 9.8" 08:20 16:28 30 21h 10m -17° 37'' -3.9 100% 9.8" 08:12 17:14

Venus Transit 12:03 12:24 12:43

Date RA Dec Mag Phase Dia Rise Set 01 19h 19m -20° 26'' +2.8 5% 9.6" 08:33 16:56 15 18h 23m -20° 19'' +0.6 30% 8.6" 06:41 15:07 30 19h 07m -21° 56'' -0.1 68% 6.4" 06:37 14:44

Mercury Transit 12:45 10:54 10:40

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–1.3. The north pole of Mars is tilted towards us at present so you should be able to see the polar cap. This is the best time to observe Mars as it is at its closest and also at its highest in the sky. So take advantage of any clear nights and go out and take a look. If you make any drawings or take images please send them to me so they can be published in Eclipse.

Jupiter is visible in the western sky during the early evening. The giant planet begins the month close to the eastern edge of Capricornus and by the 5th has crossed the border into Aquarius. By the end of the month Jupiter will have set by 19:00 so take a look early in the month while you can. This year marks the 400th anniversary of the discovery of the four largest moons of Jupiter by Galileo Galilei. These satellites, Io, Europa, Ganymede and Callisto are now known collectively as the Galilean Moons in honour of their discoverer. With a good pair of binoculars (on a tripod) or a small telescope you can see what Galileo saw when he peered through his telescope all those years ago (note that your telescope is far better than his was). As there is only a short time to observe Jupiter before it sets, there are very few satellite events visible this month . Below is a list of some that are visible. 6th - 17:01 to 20:47 Eclipse of Ganymede (only start visible) 7th - 16:46 to 19:07 Transit of Io 12th 15:31 to 18:30 Transit of Europa (only the end is visible) 12th 17:08 to 20:07 Shadow Transit of Europa (only start visible)

Saturn currently resides in the constellation of Virgo, the ringed planet rises just before midnight at the start of the month and by 22:45 at the end. Saturn reaches its first stationary point on the 14th, it moves in a retrograde direction until the end of May when it will resume direct motion. The north side of Saturn’s rings

The Planets

Date RA Dec Mag Phase Dia Rise Set 01 21h 55m -13° 36'' -2.1 100% 35" 10:29 20:14 15 22h 07m -12° 34'' -2.1 100% 34" 09:39 19:39 30 22h 20m -11° 21'' -2.0 100% 33" 08:47 18:57

Jupiter Transit 15:21 14:38 13:52

Date RA Dec Mag Phase Dia Rise Set 01/02 12h 19m +00° 21'' +0.9 100% 18" 23:29 11:47 15/16 12h 20m +00° 22'' +0.8 100% 18" 22:44 10:53 30/31 12h 19m +00° 32'' +0.7 100% 19" 21:44 09:54

Saturn Transit 05:43 04:49 03:49

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are tilted towards us by around 5° so you should be able to see them with a small telescope.

Uranus begins the month in the constellation of Aquarius very close to the border with Pisces and around mid month it moves into Pisces. At magnitude +5.9 Uranus should be visible to the naked-eye from a very dark site and an easy object to locate in binoculars. The chart show the position on new years day but it does not move very much during the month. Try your hand at locating the planet with binoculars, I don’t think there is anywhere in England where you could hope to see it without optical aid.

Neptune lies just to the southwest of Jupiter in the constellation of Capricornus. At just under magnitude +8 Neptune should be visible in binoculars and small telescopes. The chart shows the positions of Jupiter and Neptune at 18:00 on January 1st. The early part of the month is the best time to look at as Neptune, by the end of the month the planet will have set by 18:30. Neptune has a bluish colour which should help you locate it.

The Planets

Date RA Dec Mag Phase Dia Rise Set 01 21h 47m -13° 45'' +7.9 100% 2.2" 10:22 20:05 15 21h 49m -13° 36'' +7.9 100% 2.2" 09:27 19:13 30 21h 51m -13° 26'' +7.9 100% 2.2" 08:29 18:17

Neptune Transit 15:13 14:20 13:23

Date RA Dec Mag Phase Dia Rise Set 01 23h 35m -03° 28'' +5.9 100% 3.5" 11:15 22:46 15 23h 36m -03° 17'' +5.9 100% 3.4" 10:21 21:54 30 23h 39m -03° 02'' +5.9 100% 3.4" 09:23 20:58

Uranus Transit 17:01 16:07 15:11

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Overhead during January you will find this months’ featured constellation, Auriga. High in the southern sky you will fin d the celestial twins Castor and Pollux the brightest stars in the constellation of Gemini. Castor (α Gem) is a multiple star, the main pair are easily visible in small telescopes. Gemini is also home to the lovely open cluster M35 which lies close to the feet of Castor. East Gemini lies the faint constellation of Cancer, home to M44 one of the loveliest of the open clusters in Messier’s catalogue. M44, also known as Praesepe or the Beehive Cluster is visible to the naked-eye from a dark site and has been known for thousands of years. The cluster is best viewed with binoculars or a telescope using low power. The southern sky is still dominated by the superb constellation of Orion. There are

two first magnitude stars in the constellation. The dazzling blue-white Rigel; beta (β) Ori is the brightest at +0.12. Rigel marks the left foot of the hunter. The second star is the red super-giant Betelgeuse, alpha (α) Ori, which marks the right shoulder or armpit of Orion. Midway between these two stars lies the line of three bright stars that make up Orion’s Belt, from east to west (left to right) they are Alnitak, Alnilam and Mintaka. Below the belt you will find one of the finest deep-sky objects in the sky; the stunning Orion Nebula; M42. This massive cloud of gas and dust is visible

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brightness between +2.20 magnitude and +3.40. There are a number of compari-son stars close by including β Cas +2.28, α Chephi +2.44, ε Cas +3.37 and ξ Cas +3.61. An observing program for gamma Cas is available from our website. There are a couple of open clusters in Cassiopeia, M52, which lies about six degrees northwest of beta Cas and M103 which lies a short distance from delta (δ) Cas.

The crooked house shape of Cepheus can be found between Cassiopeia and Draco. Delta (δ) Cephei is another naked eye variable, An observing program available for this star from the website. High in the western sky you will find the ‘Y’ shaped Perseus, lying between Perseus and Cassiopeia is the famous ‘Double Cluster’, h and Chi (χ) Persei, also known as NGC 884 and NGC 869. The clusters are best seen in binoculars or a low power telescope. Low in the northwest you will find Constellation of Andromeda, home to our nearest large galactic neighbour, M31 the Andromeda Galaxy. M31 is visible to the naked-eye from a dark site, and a very easy object to locate with binoculars. Adjacent to Andromeda is the constellation of Triangulum home to another of our galactic neighbours M33, the Pinwheel Galaxy. Pisces, home to Uranus from the middle of the month will have set by midnight.

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to the naked-eye and an excellent object for binoculars and small telescopes. Just to the north of the M42 lies a smaller detached part of the Orion Nebula known as M43 or De Marian’s Nebula. M42 and M43 are separated by a dark dust lane. There is a third Messier object in Orion, M78; a faint reflection nebula which lies just to the north of zeta (ζ) Orionis. The nebula is illuminated by two blue A-class giant stars, both of which are around magnitude +10 To the east of Orion lies the faint constellation of Monoceros (the Unicorn). There is just one Messier object in Monoceros, the open cluster M50 which contains around 150 members spread over an area of about 15x20 arcminutes. The faint winter Milky Way runs right through the constellation from north to south. Lying below Monoceros is the small constellation of Canis Major, home to Sirius (α CMa), the brightest star in the night sky. Canis Major represents the largest of Orion’s hunting dogs, which gives rise to one of

the common names for Sirius; ‘The Dog Star’. Approximately four degrees south of Sirius lies another of Messier’s open clusters M41. With a combined magnitude of +4.5 the cluster is visible to the naked-eye from a dark site and an easy object with binoculars. The cluster has around 80 members the brightest of which are around magnitude +7.

In the southeast the long straggling constellation, Hydra rises up from the horizon. Close to the border with Monoceros you will find yet another open cluster, M48. Approximately midway between M41 and M48 lies a couple more open clusters logged by Messier M46 and M47. Directly to the north of Monoceros lies Orion’s other hunting dog Canis Minor, its brightest star Procyon (α CMi) marks the eastern point of the asterism known as the ‘Winter Triangle’ the other two points are

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Chart Produced by Chris Peat http://www.heavens-above.co

01 Jan 01:00 16 Jan 00:00 30 Jan 23:00

marked by Betelgeuse (α Ori) and Sirius. In the southeast you will find the bright constellation of Leo, home to a number of Messier objects, M65, M66, M95, M96 and M105. There are also a number of galaxies that did not make it into Messier’s catalogue.

By the early hours the morning the spring constellations of Coma Berenices, and Virgo are beginning to rise in the east. These constellations are home to a great cluster of galaxies, in a couple of months this area will be bet-ter placed for observation. Close to the eastern horizon you will find the kite shaped Boötes. To the northeast you will find the familiar asterism of the ‘Plough’ part of Ursa Major Just to the north of 23 UMa lie the nice galaxy pair M81 and M82. There are a number of other Messier objects in Ursa Major, M40 (double star), M97, M01, M108 and M109. Looking towards the north you will find Polaris; the Pole or North Star (α UMi), lying midway between the horizon and the zenith. The meandering constellation of Draco wraps itself around the north and east of Ursa Minor. To the west of Ursa Minor lies the ‘W’ shaped constellation of Cassiopeia. The central star of the ‘W’, gamma (γ) Cas is the prototype of a class of eruptive type variables. Gamma Cassiopeiae varies irregularly in

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om