掩星

2020年8月15日 Mars at the Moon’s Edge Image Credit & Copyright: Sergio Scauso Explanation: Does the Moon ever block out Mars? Yes, the Moon occasionally moves in front of all of the Solar System’s planets. Just this past Sunday, as visible from some locations in South America, a waning gibbous Moon eclipsed Mars. The featured image from Córdoba, Argentina captured this occultation well, showing a familiar cratered Moon in the foreground with the bright planet Mars unusually adjacent. Within a few seconds, Mars then disappeared behind the Moon, only to reappear a few minutes later across the Moon. Today the Moon moves close to, but not in front of, Venus. Because alignments will not have changed by much, the next two times the Moon passes through…

2020 June 21 Moon Occults Venus Image Credit & Copyright: Dzmitry Kananovich Explanation: It may look like Earthrise, but it’s actually Venus-set. Just after sunrise two days ago, both the Moon and Venus also rose. But then the Moon overtook Venus. In the featured image sequence centered on the Moon, Venus is shown increasingly angularly close to the Moon. In the famous Earthrise image taken just over 50 years ago, the Earth was captured rising over the edge of the Moon, as seen from the Apollo 8 crew orbiting the Moon. This similar Venus-set image was taken from Earth, of course, specifically Estonia. Venus shows only a thin crescent because last week it passed nearly in front of the Sun, as seen from Earth. The…

2019 August 14 Saturn Behind the Moon Image Credit: Peter Patonai (Astroscape Photography) Explanation: What’s that next to the Moon? Saturn. In its monthly trip around the Earth — and hence Earth’s sky — our Moon passed nearly in front of Sun-orbiting Saturn earlier this week. Actually the Moon passed directly in front of Saturn from the viewpoints of a wide swath of Earth’s Southern Hemisphere. The featured image from Sydney, Australia captured the pair a few minutes before the eclipse. The image was a single shot lasting only 1/500th of a second, later processed to better highlight both the Moon and Saturn. Since Saturn is nearly opposite the Sun, it can be seen nearly the entire night, starting at sunset, toward the south and…