Skywatch Line for Monday and Tuesday May 20th and 21th, written by Joe Slomka
This is the Dudley Observatory’s Skywatch Line for Monday and Tuesday May 20th and 21th, written by Joe Slomka.
The Sun sets at 8:17 PM; night falls at 10:21. Dawn begins at 3:23 AM and ends with Sunrise at 5:27.
Monday’s Moon sets at 3:48 AM and rises in Virgo at 5:35 PM, by 9 PM, it is 27° high, below the star Spica in the southeast, 30 arc-minutes in size, 94% illuminated and sets at 4:08 AM on Tuesday. Tuesday’s Moon travels to southeastern Libra, rising at 6:41 PM; by 9 PM it is 18° high, also 30 arc-minutes, 98% lit and sets at 4:32 AM on Wednesday.
Just like last week, there are no visible evening planets, but comet 13P/Olbers continues its visit western Auriga. By 9 PM, it shines with 8th magnitude, 97% lit, 18° high and sets at 11:11 PM. C/2023 A3 (Comet Tsuchinshan-Atlas) is also visible for those with moderately powerful telescopes. It appears in Virgo, glowing with 10th magnitude, highest at 9:27 PM, 48° in the South and sets at 3:41 AM.
Saturn is the first Dawn planet, rising in Aquarius at 2:44 AM, 1st magnitude, 16 arc-minutes and 24° high by 5 AM. Pisces displays Neptune and Mars. Southeastern Neptune appears 11° from Saturn, it shines with 8th magnitude, 2 arc-seconds and 21° high. Eastern Mars follows 16° behind Neptune, rises at 3:40 AM, also 1st magnitude, 5 arc seconds and 15° high. Mercury brings up the rear, rising in eastern Aries at 4:39 AM, 22° from Mars, minus zero magnitude, 6 arc-seconds, but only 4° high due to proximity to the Sun. All these planets set during the daytime.
Giovanni Schiaparelli was an Italian astronomer, born in 1835. He studied under eminent astronomers and became director of the Brera Observatory of Milan in 1860. He is recognized for discovering that meteor showers originate from comets. But he is most famous for his drawings of “canals” on Mars. In 1877, he called perceived markings on Mars “canali channels”. However, the English translation became “canals”, which imply mechanical constructions. This announcement electrified the world, including Percival Lowell. A millionaire, Lowell used his private fortune to establish a state-of-the-art observatory in Flagstaff, Arizona, with the intent of studying these “canals”. Lowell’s observations not only agreed with Schiaparelli’s, but also amplified them. Lowell wrote popular magazine articles, depicting Mars as a dying planet, whose inhabitants were desperately digging canals to water their farms. By the 1920s, observations by other astronomers debunked these notions. In the 1960s, spacecraft sent back pictures of Mars as a desert without any “canali”. American robots prowled the Martian surface and failed to find any canals, but uncovered traces of water on the now arid planet. Schiaparelli and Lowell’s “canals” are now considered to be artifacts, caused by the brain’s attempt to make sense out of unfamiliar sights.
Clear Skies Joe Slomka