Observing

  • 01-10-2016

    The January Night Sky 2017

    The General Weather patterns

    January is often a windy month. Rain is less obvious than in the previous two months, but it usually gets colder as the month ages. It can be very cold at night, often reaching freezing temperatures with clear skies. Snow can be expected in cold years. Wrap up warm with a warm hat and shoes and wear multiple layers of clothes.

    From Earth

    The Earth is at perihelion (closest to the sun) in its elliptical orbit during the first few days of the year. The winter sky, dominated by Orion, presents itself late in the evenings for most of this month. In the first half of the month, the Milky Way stretches right across the sky from east to west through the zenith at the end of evening twilight.

    The Sun

    Due to the equation of time the latest sunrise of the year occurs around the 2nd January; the mornings lighten.

    The Sun moves from Sagittarius to Capricornus on the 20th of the month. It is also beginning its journey towards more northerly latitudes once more, and will eventually become better placed for observing as the days get longer. Use appropriate, safe methods to observe the Sun and notify other members if you observe any sunspot activity. Auroral activity is quite transient, so share information with other members ASAP.

    The Moon


    The Last Quarter is on 2nd at about 05:30 in the constellation of Virgo.

    The New Moon is on 10th at about 01:30 in the constellation of Sagittarius

    The First Quarter is on 16th at about 23:25 in the constellation of Pisces.

    The Full Moon is on 24th at about 01:45 in the constellation of Cancer.

    The Moon is at perigee (nearest Earth) on the 15th and at apogee (most distant from Earth) on the 2nd. A second apogee occurs this month, on the 30th.

    The Planets

    Mercury -- is at inferior conjunction on the 14th and is best observed very early in the month following the Sun down, or very late in the month rising just before the Sun; with the added advantage that it is above the ecliptic.

    Venus -- is best observed early in the month when its elongation is largest. At this time it rises about three hours before the Sun; reducing to about one and a half hours at the end of the month. A thin waning crescent Moon joins Venus and Saturn on the morning of the 7th for a lovely photo-opportunity just before dawn. On the 9th, Venus and Saturn rise together in the south-east at around 06:00.

    Mars -- moves from Virgo into Libra on the 17th, but because the planet is moving in the same direction around the Sun as we are, it rises at about 02:30 throughout the month. The position of Mars continues to improve; it will be observable all year. In the mornings of the 3rd and 4th the waning crescent Moon accompanies Mars.

    Jupiter -- can be found in the constellation of Leo, and is well placed for serious observers; rising around 23:00 on the 1st. By the end of the month Jupiter will rise about 23:00 and culminate about 03:00. As opportunities for observing Jupiter improve; it is at opposition on the 8th March, it is worth reminding members that there is much to see in a decent telescope. The Great Red Spot is visible, of course, even though it is much smaller than usual for some unknown reason, and if you have good-seeing you may well make out the belts too. Galilean Moons with their accompanying shadows can be observed quite often. On the morning of the 28th the waning gibbous Moon joins Jupiter.

    Saturn -- is to be found in Ophiuchus throughout this month, rising at about 06:00 at the start, and 04:00 at the end. Apart from the photo-opportunity on the 7th with the Moon and Venus, Saturn’s rings are always fascinating. It is in opposition on the 3rd June, so some good observing to be had this year.

    Uranus -- is best observed at the beginning of the month. At this time, it can be found in the constellation of Pisces at RA 1h 02m 05s, Declination 5º 55' 49". At a magnitude of 5.81 it may well be seen with binoculars. A small telescope might show a blue hue, but since Uranus usually has few features, little else may be seen even with a larger amateur instrument.

    Neptune -- is also visible using a decent telescope, in the early evening until about 20:00 during January. It can be found in the constellation of Aquarius at RA 22h 38m 13s, Declination -9º 28' 01", at a magnitude of 7.93. Neptune is also best observed in early January.

    Meteors

    TheQuadrantids can be seen from 1st to 6th January. The ZHRs varies between 40 and 110 and are at their best on the morning of the 3rd or 4th. The radiant, in northern Boötes, is circumpolar and lies, towards Alkaid the last star in the tail of Ursa Major, in a part of the sky that once contained a constellation called Quadrans Muralis; the Mural Quadrant! Just before twilight (near the maximum), the radiant is near the zenith. These meteors are relatively slow, but brighten just after maximum with occasional green, yellow or blue hues. This year the waning crescent Moon affords a nearly favourable combination. The Quadrantids’ associated comet is not known for certain.


    Taurus (Pronounced TAW-rus)

    Some say that the constellation of the Bull was depicted in caves by humans tens of thousands of years ago to the extent that even the Pleiades were shown. What is certain is that Taurus the Bull, with the Scorpion and the Lion, was portrayed over 6000 years ago in the Euphrates Valley, in ancient Mesopotamia as one of the constellations found in the zodiac; the band of stars through which the Sun, Moon and planets pass.


    A feature of note is the vee-shaped face of the bull is a very clear asterism and finding it should be no problem. It is due south at nine in the evening in mid-January. You can also follow the line of the belt of Orion towards the north-west and locate it just before reaching Pleiades. This asterism is known as the Hyades, and is the nearest open cluster to us. The brightest star in the constellation, the red giant star Aldebaran, is prominent in the vee and is described as the right eye of the bull, even though its name means the ‘follower’ of the Pleiades in medieval Arabic. As an open cluster many of these stars have similar distances and are moving with similar proper motions through space.

    The Pleiades are another example of an open cluster and is worthy of some attention with binoculars, if you have no telescope. Although they are also known as the Seven Sisters, there are more than 1000 stars in this cluster which lies around 440 light-years away. The oldest of them are about 150 million years old and the slight haze that you see around the stars is a gas and dust cloud through which they are moving. The light from the nearest stars is reflected back towards us and the spectacle is known as a reflection nebula.

    The ecliptic (the path of the Sun) passes between these clusters; within 5° or so of both, and the Moon and sometimes the planets can present a lovely photo-opportunity. A lunar occultation can be particularly satisfying to observe.

    At the end of the right horn of the Bull, in the east of Taurus is M1 (Messier 1) (O). It was here in 1054 that Chinese astronomers saw a new star, a stella nova. Its remnant, known as the Crab Nebula, can just be observed with binoculars under good seeing conditions. At its core lies a neutron star spinning at 30 times per second, spraying out radiation like a lighthouse, a pulsar. This is the first supernova remnant to be identified with its historic supernova explosion.

    North of Aldeberan, just above the horn, is a variable star called T Tauri which is the prototype of a class of pre-main-sequence stars. T Tauri stars are around 100 million years old just prior to main sequence burning. It is in this locality and into Auriga to the north that we find one of the closest regions of active star formations.

    Myths

    Greek

    According to Greek mythology Zeus disguised himself as a bull to further pursue Europa, the princess of Phoenicia. He mingled with a herd near her and soon attracted her attention for he was the most handsome of creatures. His hide was pure white like virgin snow, and his muscular neck held his head high with horns like burnished metal. She was taken with his gentle nature and was tempted to ride into the sea on his back. It was when they reached Crete that Zeus made known his identity. One of their offspring was said to be Minos king of Crete who created the palace at Knossos where the bull games were enacted.

    Some say the image of the constellation of Taurus show no rear-end because the bull is immersed in water.


    David J Thomas

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