Some of the most spectacular viewing events take place when the Moon is around, and it does so most gloriously when it aligns perfectly with the Sun, producing a total solar eclipse. Unfortunately, a repeat of the total eclipse of August 11, 1999 is not scheduled, but we will be able to watch the Moon whiz around the wonderful Pleiades open cluster (Messier 45) 25 years later on August 26, 2024.
The Moon will come close quite frequently, and more occasionally occult bright deep-sky objects that lie about 5° north or south of the ecliptic, the Sun's apparent path around the sky to which the planets and Moon adhere. The Moon's orbit is inclined about 5° to the plane of Earth's orbit around the Sun, so our satellite can stray farther. The Pleiades, certainly, and the Beehive cluster (M44 in Cancer) are probably the main deep-sky objects that can get in the Moon's way.
On the night of 25/26 August, the last quarter Moon and the Pleiades will rise in the eastern sky at around 22:00 BST, with a separation of about 3° between the stars in Taurus. However, the Moon is rapidly drawing closer, so that by 1:00, when the pair clear the horizon by more than 20°, the distance between them will have halved, with the Moon now 1.5° from Merope, one of the Seven Sisters. Watch with a pair of binoculars as the Moon slides across the southernmost edges of the Pleiades between 3:00 and 5:00.
Finally, the Moon does more damage when it moves in front of the +3.6 magnitude star Atlas (27 Tauri), the easternmost star in the Pleiades. Altas sets at the Moon's bright edge at 4.52am BST, and reappears in strong twilight around 5.30am. A telescope will provide an excellent view of this event.
