SkyEye

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

January 2009

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	Thu
2	Fri
3	Sat	The waxing crescent Moon poses no problems for observing the Quadrantids.
4	Sun	Earth at perihelion
		First Quarter Moon
		Mercury at greatest elongation east
5	Mon
6	Tue
7	Wed	Moon occults the Pleiades: visible from about 1600 UT in northern Europe, Asia, northern Alaska and Canada, Greenland and Iceland.
8	Thu
9	Fri
10	Sat	Moon at perigee: Because perigee occurs so close to the Full Moon, especially high tides are expected.
10	Sat	Comet C/2007 N3 Lulin at perihelion
11	Sun	Full Moon
12	Mon
13	Tue
14	Wed	Venus at greatest elongation east
15	Thu
16	Fri
17	Sat
18	Sun	Last Quarter Moon
19	Mon
20	Tue	Mercury at inferior conjunction
21	Wed	Moon occults Antares during daylight hours.
22	Thu
23	Fri	Moon at apogee
24	Sat	Jupiter at conjunction
25	Sun	Moon occults Mars: visible in the Antarctic.
26	Mon	New Moon
26	Mon	An annular solar eclipse is visible from parts of the Indian Ocean and Indonesia.
27	Tue
28	Wed
29	Thu
30	Fri
31	Sat

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 4 January. The date of perihelion can range from New Year's Day to 4 January.
Mercury: Capricornus -> Sagittarius
The closest planet to the Sun is best observed from the northern hemisphere during the first half of the month. At greatest elongation east on 4 January, it plunges towards the western horizon after sunset, disappearing from view by mid-month. At inferior conjunction on 20 January, Mercury reappears in the east as a morning sky object at the end of the month.
Venus: Aquarius -> Pisces
The "evening star" still commands the western skies after sunset. It is best seen from northern latitudes where it continues to climb higher above the horizon. However, it appears to be getting lower in the sky when seen from the southern hemisphere. Venus reaches greatest elongation east on 14 January.
Comet C/2007 N3 Lulin: Libra
In July 2007, university student Quanzhi Ye discovered this comet from images taken at Lulin Observatory in Taiwan. Comet C/2007 N3 Lulin should be visible to the naked eye as it reaches a perihelion distance of approximately 1.2 AU on 10 January. Its closest approach to Earth occurs late next month when it may reach fourth magnitude.
Mars: Sagittarius
It is very difficult to see the red planet in the east, rising just before the Sun. It is occulted by the Moon on 25 January.
Jupiter: Sagittarius -> Capricornus
The largest of the planets in the solar system, Jupiter may be visible low in the west early in the month, but it soon disappears in the glare of the Sun as it approaches conjunction on 24 January.
Saturn: Leo
The ringed planet shines at first magnitude when it rises late in the evening.
Uranus: Aquarius
The most distant of the naked-eye planets undergoes conjunction in March so it is getting difficult to see in the western sky, setting by mid-evening.
Neptune: Capricornus
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 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 at Furman University.

The SkyEye banner features a view of Saturn from its satellite Iapetus and is courtesy of NASA/JPL/Space Science Institute. Of all the major satellites of Saturn, Iapetus is the only one with a significant orbital inclination. Thus, whilst the rings appear nearly edge-on from all of the other major satellites, from Iapetus they are usually seen at a tilt. This image was taken during the Cassini-Huygens mission on 10 September 2007 and consists of 15 red, green and blue spectral filter images.