By Richard Hall
All times are adjusted for daylight saving
The chart shows the heliocentric orbital positions of the planets for December 1st 2008 & January 2009. The planets are orbiting in an anti-clockwise direction and smaller images show the positions of the inner planets for the 15th. The orbits of the inner planets, Mercury, Venus, Earth and Mars, are to scale. Planets beyond Mars are placed in shells. These are Ceres, Jupiter, Saturn, Uranus, Neptune, Pluto, and Eris. A line drawn from the Earth through the Sun reveals the constellation of the Zodiac that the Sun is moving through. Because the Earth rotates in an anti-clockwise direction planets to the right of this line rise after midnight and are therefore morning stars. Those to the left are evening stars.
| MERCURY - is not well placed for observation in December and January. The planet was at superior conjunction (the far side of the Sun) on November 26th. Thereafter it moved into the western evening sky but will not be visible to the unaided eye until late December and early January. On January 5th it reaches greatest elongation when it will be 19 degrees east of the Sun. However, even then it will be difficult to see as it sets in twilight an hour after the Sun. A few days after elongation it will be lost from view as it moves back towards the Sun reaching inferior conjunction (a point between the Earth and the Sun) on January 21st. In the last week of January it will reappear in the eastern dawn twilight. At Stardate, January 24th, it will rise at 5:54am, 22 minutes before the Sun |  | VENUS - is the brilliant evening star and reaches greatest elongation on January 15th. On this date it will be 47 degrees east of the Sun. At Stardate, January 24th, Venus will be in Aquarius and sets at 10:45pm, almost 2 hours after the Sun. Its magnitude will be -4.6 and in a telescope it will be seen to have a crescent phase (46%), 27.3” in diameter |  | MARS - reaches solar conjunction (it will be on the far side of the Sun) on December 6th and will not be visible until mid-January when it will reappear in the dawn twilight. At Stardate, January 24th, Mars will be in Sagittarius and rises at 5:09am, 67 minutes before the Sun. On this date its magnitude will be +1.3 and in a telescope it will show a tiny disc 3.9” in diameter.. | 
| JUPITER - will be setting in the evening twilight by mid-December and will be lost from view in early January. The planet reaches solar conjunction (it will be on the far side of the Sun) on January 24th. Thus, Jupiter will not be visible at Stardate. |  |
SATURN - is a morning star in December but will be rising before midnight after the 7th of January. Saturn is in Leo and at Stardate on January 24th it will rise at 10:53pm. Its magnitude will be +0.8 and its telescopic diameter 19.2”. |  | URANUS - is in the constellation of Aquarius and will be setting before midnight after January 5th. At magnitude +5.9, Uranus is just visible to the unaided eye from a dark sky site. In a telescope it will be seen as a tiny greenish disk 3.4” in diameter.
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NEPTUNE - is in the constellation of Capricornus and will be setting before midnight after the 20th of December. At magnitude +8.0 the planet is visible in binoculars and, in a telescope it will be seen as a tiny bluish disk 2.2” in diameter.
|  | PLUTO - is in the constellation of Serpens Cauda and reaches solar conjunction (it will be on the far side of the Sun) on December 22nd. Pluto will re-emerge in the eastern dawn twilight in mid-January. At magnitude +14.1 it is visible only in large telescopes |
CONJUNCTIONS & OCCULTATIONS Conjunctions and occultations visible from New Zealand in December & January are listed below. A conjunction occurs when two celestial objects come close together in the sky. An occultation occurs when one celestial object moves in front of another. The hour given is the time of closest approach for a conjunction or the approximate time of disappearance of one object behind another in the case of an occultation. The exact time of an occultation, and its duration, will depend upon the observer’s latitude and longitude. Phase gives the direction that the illuminated side of the moon is pointed. The phase is pointed west between new and full moon, and east after.
DECEMBER 01st Venus 2o south of Jupiter (2pm) 02nd Jupiter 1.3o north of the Moon (4am, crescent west) Venus 0.8o south of the Moon (5am, crescent west) 04th Neptune 1.4o south of the Moon (4pm, crescent west) 25th Antares 0.09o south of the Moon (8pm, crescent east) 27th Venus 1.5o south of Neptune (3pm) 29th Mercury 0.7o south of the Moon (5pm, 1day crescent west) Jupiter 0.6o north of the Moon (10pm, 1day crescent west) 31st Mercury 1.3o south of Jupiter (7pm) Neptune 1.7o south of the Moon (midnight, crescent west)
JANUARY 22nd Antares 0.02o south of the Moon (2am, crescent east) 24th Venus 1.4o north of Uranus (5am) Asteroid Fides occulted by Moon (6am, crescent east) 28th Neptune 1.8o south of the Moon (7am, crescent west) 31st Venus 2.8o south of the Moon (1am, crescent west)
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