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The Night Sky
(January 2016)
UT (Universal Time) or GMT is used this month.
©
22:00 hours early in the month
21:00 hours in the middle of the month
20:00 hours at the end of the month
January
The General Weather Pattern
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 on the evening of the 2nd of January. 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.
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.
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
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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
The Quadrantids 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 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 TOR-us)
Astronomy
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.
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. The 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
only just be seen with good sized binoculars, used properly under good
seeing conditions in dark sky conditions. It is recommended to view it
in a telescope of at least 4 inches (100mm). It has a magnitude of 8.40.
Try searching for it with a telescope. At its core lies a neutron star
spinning at 30 times per second, spraying out radiation like a
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lighthouse; a pulsar. This is the first supernova remnant to be identified with its historic supernova explosion.
North-west of Aldeberan, next to the Bull’s left eye, Ain, 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 when they go through this phase, 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.
Greek Myths
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 only when they reached Crete that
Zeus made known his identity. One of their offspring was said to be king Minos 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.
NB
Log on to uskastronomicalsociety.org.uk each month for more from Dr David. P. Thomas.
Conditions apply as to the use of this matter. © D J Thomas