View Full Version : Saturn at Greatest Brilliance MAR 24 - Opposition APR 03

2011-Mar-18, 11:38 PM
Saturn is now visible in the southeastern sky for much of the evening as it approaches opposition from the Sun. The ringed planet’s oppositions are slowly moving into a warmer time of the year for observers north of the tropics. However, that also means its declination has begun dipping into the southern celestial hemisphere where it will remain until 2026.

Saturn is expected to achieve its greatest brilliance for this apparition around 2011 MAR 24 at magnitude +0.3. This year it will reach opposition from the Sun in ecliptical longitude on APR 03, along with its closest approach to Earth of this apparition at 8.6139 AU. On that date the tilt of its ring plane will be 8.7°, and its equatorial angular diameter will be 19.2 arcseconds. It will then be rising around sunset, transiting near local midnight, and setting as the Sun rises.

Apparent direct motion will resume on JUN 12, and eastern quadrature (90° from Sun) will be reached on JUL 02 Eventually Saturn will move to conjunction behind the Sun on OCT 13.

The only close conjunctions between Saturn and other planets during this apparition will occur in the glare of the Sun shortly before Saturn conjuncts with the Sun. On SEP 29 Venus will pass 1.3° south of Saturn, and on OCT 06 Mercury will pass 1.7° south of Saturn.

On JAN 24 Saturn approached to 8.2° from magnitude +1.0 Spica before retrograde motion pulled it back. Saturn will not come close to any other first magnitude stars during this apparition.

The Moon will pass about 7° or 8° south of Saturn on MAR 20, APR 16, MAY 14, JUN 10, JUL 07, AUG 04, AUG 31 & SEP 28.

I’ve created several graphics related to Saturn and the changes in the tilt of its rings. They can be seen by clicking: http://www.curtrenz.com/saturn

Photos and descriptions of Saturn and its rings would be welcome additions to this thread.

2011-Apr-02, 04:14 PM
Opposition arrives tomorrow! Magnificent Saturn with its glorious rings is the only significant planetary show right now with the others appearing rather close to the Sun. Here are my calculated times for the various events related to Saturn’s opposition.

2011 APR 03 at 22:49 UT – Closest Approach to Earth
2011 APR 03 at 23:55 UT – Greatest Elongation from Sun
2011 APR 03 at 23:56 UT – Opposition in Celestial Longitude
2011 APR 05 at 01:48 UT – Opposition in Right Ascension

Saturn’s greatest brilliance for this apparition came on 2011 MAR 24 due to the decreasing tilt of its ring plane while the planet appears in retrograde motion. Enjoy the show! http://www.curtrenz.com/saturn