SkyEye

Welcome to SkyEye, your guide to this month's celestial events.

January 2012

The Calendar

All times and dates are given in Universal Time (UT).
Nightly darkness estimates are calculated for 45° N and 30° S.
Like total solar eclipses, lunar occultation events can be seen only from limited regions on Earth (and sometimes not at all if the occultation takes place during daylight hours). However, the Moon will appear close in the sky to its 'target' for some hours either side of the actual occultation, regardless of where you are.

Date		Event
1	Sun	First Quarter Moon
2	Mon	Moon at apogee
3	Tue
4	Wed	The waxing gibbous Moon sets shortly after midnight in the northern hemisphere, leaving dark skies for observing the Quadrantids (theoretical peak activity: 07:20 UT).
5	Thu	Earth at perihelion
6	Fri
7	Sat
8	Sun
9	Mon	Full Moon
10	Tue
11	Wed
12	Thu
13	Fri
14	Sat
15	Sun
16	Mon	Last Quarter Moon
17	Tue	Moon at perigee
18	Wed
19	Thu	Saturn at west quadrature
20	Fri
21	Sat
22	Sun	Jupiter at east quadrature
23	Mon	New Moon
24	Tue
25	Wed
26	Thu
27	Fri
28	Sat
29	Sun
30	Mon	Moon at apogee
31	Tue	First Quarter Moon

Coming up next month...

Unfortunately, the southern hemisphere's Alpha Centaurids meteor shower is washed out by the Full Moon.

Because the Moon exhibits the First Quarter phase twice this month, it won't reach that phase next month, the shortest month of the year. However, it will again go through First Quarter twice in the following month of March.

The Solar System

The word planet is derived from the Greek word for 'wanderer'. Unlike the background stars, planets seem to move around the sky, keeping mostly to a narrow track called the ecliptic, the path of the Sun across the stars. Dwarf planets and small solar-system bodies, including comets, are not so constrained, often moving far above or below the ecliptic.

Sun: Sagittarius » Capricornus
The Earth makes its annual closest approach to the Sun on 5 January. The date of perihelion can range from New Year's Day to 5 January.
Mercury: Ophiuchus » Sagittarius » Capricornus
Found in the east just before sunrise, this elusive planet is sinking back towards the horizon on its way to conjunction early next month. Look for it early in the month before it's lost in solar glare.
Venus: Capricornus » Aquarius
The 'evening star' shines brightly above the western horizon after sunset. The northern hemisphere is finally starting to get some good views of this planet as it climbs ever farther from the Sun. However, for southern observers, Venus stays pretty much at the same altitude for the month, descending only slightly.
Mars: Leo » Virgo
The red planet now rises by mid-evening and spends most of the month circling under the lion's feet.
Jupiter: Aries
Dazzling Jupiter still commands the skies after sunset, not setting until after midnight. This may be the best time to observe the interesting shadow effects of the planet's disc on its largest moons (and vice versa) with east quadrature occuring on 22 January.
Saturn: Virgo
The ringed planet is still a morning sky object but is rising earlier and earlier before the Sun. Look for its appearance in the eastern sky after midnight. At west quadrature on 19 January, this is an especially good time to observe the interplay of shadows - planetary disc, rings and moons - in the Saturnian system.
Uranus: Pisces
At east quadrature last month, this greenish-coloured gas giant sets before midnight.
Neptune: Aquarius
A small telescope is necessary to view the most distant planet in the solar system. However, with conjunction approaching next month, it is probably too close to the Sun to easily observe.

The Celestial Sphere

Constellations are patterns of stars in the sky. The International Astronomical Union (IAU) recognises 88 different constellations. The brightest stars as seen from the Earth are easy to spot but do you know their proper names? With a set of binoculars you can look for fainter objects such as nebulae and galaxies or some of the closest stars to the Sun.

Descriptions of the sky for observers in both the northern and southern hemispheres are available for the following times this month. Subtract one hour from your local time if summer (daylight savings) time is in effect.

Local Time	Northern Hemisphere	Southern Hemisphere
1730 hours (1830 hours summer time)	45° N	30° S
1930 hours (2030 hours summer time)	45° N	30° S
2130 hours (2230 hours summer time)	45° N	30° S
2330 hours (0030 hours summer time)	45° N	30° S
0130 hours (0230 hours summer time)	45° N	30° S
0330 hours (0430 hours summer time)	45° N	30° S
0530 hours (0630 hours summer time)	45° N	30° S

For More Information...

Consult our online glossary for non-technical explanations of many of the astronomical terms used in these pages.
Blue moons, eclipses, the dates of Easter and much more can be found at the Interactive Astronomy Pages.
For more information about the objects and events described in SkyEye, visit these astronomy-related sites.

Credits

Much of this information can be found in this month's issue of your favourite amateur astronomy magazine available in your local bookshop. Another excellent source is the current edition of the Astronomical Calendar by Guy Ottewell and published by the Universal Workshop.

The SkyEye banner features the supernova remnant known as the Crab Nebula. Six light years wide and 6500 light years distant, this expanding nebula is the shattered remains of a star that blew up nearly a thousand years ago. At its heart beats a pulsar, a neutron star which spins at the incredible rate of 30 times per second. The supernova explosion which produced this object was observed in 1054 in China, Japan and Arabia. It was also seen in North America by the Anasazi people who lived in what is now New Mexico and who depicted it in a petroglpyh. This image is a composite assembled from 24 individual exposures taken by the Hubble Space Telescope in October 1999, January 2000 and December 2000, and is courtesy of NASA, ESA, Jeff Hester and Allison Loll (Arizona State University). The colours represent different elements which were expelled during the explosion: neutral oxygen (blue), doubly-ionised oxygen (red) and singly-ionised sulphur (green). These elements will find their way into the next generation of stars and planets (and extra-terrestrial life?).