March Night Sky Brings Spectacular Events: Saturn’s Vanishing Rings, Lunar Occultation of the Pleiades, Mercury’s Greatest Eastern Elongation, and Planetary Conjunctions!
The night sky in March is full of excitement! The lunar occultation of the Pleiades on the 5th (Tuesday), Mercury’s greatest eastern elongation on the 8th (Friday), the disappearance of Saturn’s rings on the 24th (Sunday), and a series of planetary conjunctions with the Moon are all celestial events worth watching. Don’t miss this cosmic feast!Saturn, often hailed as the most beautiful planet in the solar system, is famous for its magnificent rings extending along its equatorial plane, spanning 280,000 kilometers. However, these rings are only 10 meters to 1 kilometer thick. Every 13 to 15 years, when Saturn's equatorial plane aligns perfectly with Earth, its rings appear to vanish because they are seen edge-on, with their tilt reaching 0 degrees. Even with a telescope, they become nearly invisible. The last occurrence was on August 11, 2009, and after 15 and a half years, this phenomenon will reappear on March 24. Unfortunately, Saturn will be too close to the Sun for observation.Starting in March, Saturn will exit the visible lineup of the seven major planets, while the Moon will sequentially meet other planets. The most stunning event is the Mercury-Moon Conjunction on the 1st (Saturday), when a slender crescent Moon will shine above Mercury before 19:00. This will be followed by the Venus-Moon Conjunction on the 2nd (Sunday), the Jupiter-Moon Conjunction on the 6th (Thursday), and the Mars-Moon Conjunction on the 9th (Sunday), each presenting its own unique charm.During its journey past the planets, the Moon will also pass through the brightest star cluster in the night sky—the Pleiades, commonly known as the "Seven Sisters." From 21:00 to midnight on March 5, this event can be enjoyed with the naked eye. Through binoculars, observers can witness the 4.3-magnitude star Atlas in the Pleiades being occulted by the Moon’s dark edge at 21:26 and reappearing at 22:24, while the 3.9-magnitude star Pleione will disappear at 21:52 and re-emerge at 22:27.The first greatest eastern elongation of Mercury this year will occur on March 8, when Mercury will be 18.2 degrees away from the Sun. It will be positioned low in the western sky after sunset, shining at an apparent magnitude of -0.4. If weather conditions permit, observers can spot this bright, white-glowing planet— the closest to the Sun—between 18:30 and 19:00 in an open western horizon a few days before and after the event.For more detailed information on these astronomical events, please visit the Taipei Astronomical Museum website.