Welcome to SkyEye, your guide to this month's celestial events. All times and dates are given in Universal Time (UT). Nightly darkness estimates are calculated for Greenwich, London (51.5° N, 0° W).
| Date | Event | |
|---|---|---|
| 1 | Fri | |
| 2 | Sat | Moon at perigee |
| 3 | Sun | Uranus at east quadrature |
| 4 | Mon | |
| 5 | Tue | Full Moon |
| 6 | Wed | The Phoenicid meteor shower is obliterated by the nearly full Moon. |
| 7 | Thu | Similarly, the Puppid-Velid meteor shower is ruined by the bright waning Moon. |
| 8 | Fri | |
| 9 | Sat | |
| 10 | Sun | Moon occults Saturn: barely and briefly visible from the north pole. |
| 11 | Mon | |
| 12 | Tue | Last Quarter Moon |
| 13 | Wed | Moon at apogee |
| 14 | Thu | The radiant of the Geminid meteor shower is up nearly all night for northern hemisphere viewers so the late-rising waning crescent Moon hardly interferes with observations of this annual event. |
| 15 | Fri | Moon occults first-magnitude star Spica: daylight event. |
| 16 | Sat | |
| 17 | Sun | |
| 18 | Mon | |
| 19 | Tue | Moon occults first-magnitude star Antares: daylight event. |
| 20 | Wed | New Moon |
| 21 | Thu | |
| 22 | Fri | Earth at solstice |
| With the Moon barely past new, conditions could hardly be more favourable for watching the Ursid meteor shower. | ||
| 23 | Sat | |
| 24 | Sun | |
| 25 | Mon | Moon occults Uranus: the end of the event is visible in the mid-Atlantic Ocean from approximately 2100 UT. |
| 26 | Tue | |
| 27 | Wed | First Quarter Moon |
| 28 | Thu | Moon at perigee |
| 29 | Fri | |
| 30 | Sat | |
| 31 | Sun | |
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 are not so constrained, often moving far above or below the ecliptic.
| Object | Location | Description |
|---|---|---|
| Sun | Ophiuchus -> Sagittarius |
As seen from Earth, the Sun reaches the point farthest south of the celestial equator on 22 December. At this solstice, days are at their shortest in the northern hemisphere and at their longest in the southern hemisphere. |
| Mercury | Libra -> Scorpius -> Ophiuchus -> Sagittarius |
The best views of this elusive planet are from the northern hemisphere this month. Not very high in the sky, it is descending towards the eastern horizon in the dawn sky. Look for it in close proximity with the planets Mars and Jupiter as well as the star Graffias on 10-11 December. |
| Venus | Ophiuchus -> Sagittarius |
The "evening star" is still near the western horizon after sunset but it is slowly climbing higher as the month progresses. |
| Mars | Libra -> Scorpius -> Ophiuchus |
The red planet is difficult to see in the east at dawn. It forms an interesting grouping with planets Mercury and Jupiter as well as the star Graffias on 10-11 December. |
| Jupiter | Libra -> Scorpius -> Ophiuchus |
At conjunction last month, the largest planet is still difficult to see in the dawn sky. It passes near the star Graffias on 9 December, the planet Mercury on 10 December and finally the planet Mars on 11 December. |
| Saturn | Leo | The ringed planet rises in mid-evening, just as Neptune sets. Polar bears may see it briefly occulted by the Moon on 10 December. |
| Uranus | Aquarius | Barely visible to the naked eye, Uranus reaches east quadrature on 3 December and is occulted by the Moon on Christmas day. This gas giant sets before midnight so look for it in the west after sunset. |
| Neptune | Capricornus | A small telescope is necessary to view the most distant planet in the solar system. It sets by mid-evening, making it very difficult to observe this month. |
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 |
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 image of the Sun in the SkyEye banner is courtesy of the SOHO/EIT consortium. The composite image from May 1998 combines EIT images from three wavelengths (171Å, 195Å and 284Å) into one that reveals solar features unique to each wavelength. SOHO is a project of international cooperation between ESA and NASA.
Copyright © 1995-2006 by David Harper and L.M. Stockman