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arfis
2010-Aug-24, 09:19 AM
Jupiter is close to the first point of tropical Aries and Saturn is close to the first point of tropical Libra. This affords a good opportunity to see in the sky how far the equinoxes have precessed since the time of Christ. At Year 1, the tropical equinoxes occurred where the ecliptic crossed the celestial equator at the first fish of Pisces, and on the Libra side of Virgo close to the star Spica.

The equinoctial points have since moved about 25 degrees of arc against the stars due to the earth's spin wobble, and are now close to the circlet at the end of the second fish of Pisces - the point now occupied by Jupiter and Uranus, and near the Leo end of Virgo - close to Saturn. Venus and Mars will conjunct Saturn in the evening sky in early August. Uranus may be just visible next to Jupiter with the naked eye on a dark night.

PetersCreek
2010-Aug-25, 12:09 AM
Moved to the Astronomy forum.

Robert Tulip
2010-Aug-25, 01:51 PM
Jupiter is close to the first point of tropical Aries and Saturn is close to the first point of tropical Libra. This affords a good opportunity to see in the sky how far the equinoxes have precessed since the time of Christ. At Year 1, the tropical equinoxes occurred where the ecliptic crossed the celestial equator at the first fish of Pisces, and on the Libra side of Virgo close to the star Spica.

The equinoctial points have since moved about 25 degrees of arc against the stars due to the earth's spin wobble, and are now close to the circlet at the end of the second fish of Pisces - the point now occupied by Jupiter and Uranus, and near the Leo end of Virgo - close to Saturn. Venus and Mars will conjunct Saturn in the evening sky in early August. Uranus may be just visible next to Jupiter with the naked eye on a dark night.Thanks Arfis for drawing attention to this. Jupiter and Saturn are prominent in the night sky at the moment, although Saturn is fairly close to the sun. People may be interested to see the original context of these remarks (http://www.bautforum.com/showthread.php/98512-Planet-Positions-for-2010). From the source diagram we can see that Jupiter moved back into the southern hemisphere on 15 August, very close to Uranus which will move back to the southern hemisphere on 10 September. Both will return to the northern hemisphere in 2011. The first point of tropical Aries is where the zodiac crosses the celestial equator.