SkyEye

Welcome to SkyEye, your guide to this month's celestial events. All times and dates are given in Universal Time (UT). Daily darkness estimates are calculated for Greenwich, London (51.5° N, 0° W).

Calendar of Events - December

DateEvent
5Sun Last Quarter Moon
6Mon The Moon should not interfere with observations of the Phoenicids meteor shower which is expected to peak at about 0230 UT. However, with activity from this shower often almost nonexistant, a better bet may be the Puppid-Velids meteor shower which peaks on the same day.
7Tue Moon occults Jupiter
10Fri Mercury at inferior conjunction
12Sun New Moon
Moon at perigee
13Mon Pluto at conjunction
A practically new Moon means perfect viewing conditions for the Geminids meteor shower. It peaks at about 2230 UT.
18Sat First Quarter Moon
21Tue Solstice occurs on our planet today, marking the beginning of winter in the northern hemisphere and the start of summer in the south.
22Wed The waxing gibbous Moon badly interferes with the Ursids meteor shower.
26Sun Full Moon
27Mon Moon at apogee
29Wed Mercury at greatest elongation west

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.
Sun
Location: Ophiuchus -> Sagittarius
Comet C/2003 K4 (LINEAR)
Location: Hydra
This comet begins to fade from view as it continues its journey toward the constellations making up the legendary ship Argo.
Mercury
Location: Ophiuchus
Mercury disappears from western skies early in the month as it heads towards conjunction on 10 December. It reappears in the east before sunrise late in the month, rising rapidly for southern hemisphere viewers and becoming quite high.
Venus
Location: Libra -> Scorpius -> Ophiuchus
The "morning star" is quite low in the east before sunrise. It appears to be maintaining altitude from southern latitudes but is sinking quickly from the vantage point of the northern hemisphere.
Mars
Location: Libra -> Scorpius
Mars remains a difficult morning sky object, rising just ahead of the Sun.
Jupiter
Location: Virgo
Like last month, the Moon occults the planet Jupiter. Unlike last month, this event will be visible during the hours of darkness. At approximately 11 UT on 7 December, observers in the eastern and mid-western United States plus southeastern Canada will be able to watch the largest planet in the solar system disappear behind the disc of the Moon.
Saturn
Location: Gemini
The Huygens probe separates from the Cassini orbiter in preparation for its plunge into Saturn's largest moon, Titan. The ringed planet is visible nearly all night as it heads for conjunction early next year.
Uranus
Location: Aquarius
The sixth-magnitude planet sets in mid-evening.
Neptune
Location: Capricornus
Binoculars or a small telescope will be necessary to see Neptune before it sets in early evening.
Pluto
Location: Serpens (Cauda)
With a brightness of around fourteenth magnitude, the smallest planet in the solar system can be seen only through a good-sized telescope. However, because it is at conjunction this month, it will be lost in the Sun's glare and impossible 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 daylight savings time is in effect. (Note: These times are approximate.)

Northern Hemisphere : 45° N

Southern Hemisphere : 30° S

For More Information...

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 image of the Sun in the SkyEye banner is courtesy of the SOHO/EIT consortium. SOHO is a project of international cooperation between ESA and NASA. Used with permission.


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