Skywatch Line for Wednesday and Thursday, May 8 and 9, 2024, written by Alan French
This is Dudley Observatory’s Skywatch Line for Wednesday and Thursday, May 8 and 9, 2024, written by Alan French.
The Sun rises at 5:40 A.M. on Wednesday and sets at 8:04 P.M. On Thursday it rises at 5:39 and sets at 8:05. This Thursday has just over 16 ½ more minutes more daylight than last Thursday.
The Moon was new late Tuesday and is returning to the evening sky and moving toward first quarter. Wednesday evening offers a rare opportunity to catch a very young Moon, less than a day old, soon after sunset, but you’ll need an excellent view to the west northwest and clear skies down to the horizon to spot the slender crescent. At 8:34 P.M., 30 minutes after sunset, the Moon will be 5 ½ degrees above the horizon and only 1% illuminated. Bright evening twilight will impede your chances of spotting such a thin Moon, and some optical aid, binoculars or a small telescope, will aid the search and improve your chances. It is important to carefully focus on a star or distant object before searching for the Moon. If skies are transparent, Sirius should be visible low toward the southwest, and Vega low in the northeast. A distant terrestrial object can also be used.
As the Sun moves farther below the horizon twilight will fade, but the Moon will also move lower and its light will pass through a thicker layer of atmosphere. By 8:44 the Moon will be 4 degrees high and 8:54 will find the Moon just 2 ½ degrees above the horizon. The Moon will set at 9:16. If you spotted the Moon at 8:34 it was just 21 hours, 12 minutes old.
A lovely crescent Moon will be higher and easier to spot on Thursday night. At 8:30 P.M. a 4 ½% illuminated crescent will be almost 18 degrees high in the western sky. By 9:30 it will still be 8 degrees above the horizon, a little farther north, and against darker skies. It should be a lovely sight.
At 10:00 P.M. the bright, reddish-orange star, Arcturus, is high in the southeast. Arcturus is the brightest star in the northern hemisphere and the fourth brightest in the night sky. Like many bright stars, it is bright because it is a relatively close neighbor, lying only 37 light-years away. Back when plans for the 1933 Chicago World’s Fair were being made, astronomers believed Arcturus was 40 light-years away. Since the previous, 1883 Chicago World’s Fair was 40 years earlier, the light from Arcturus, collected by the 40-inch Yerkes refractor and converted into an electric by a photo-electric cell, was used to turn on the lights at the 1933 fair. Thus, the fair was started by light that left Arcturus during the previous fair.
Arcturus is the brightest star in the constellation Boötes, the Herdsman. The bright stars of Boötes form a pattern looking like a kite, stretching upward and to the left from Arcturus around 10:00 P.M. now.
The first manned flight of the Starliner spacecraft was scrubbed Friday night. The rescheduled launch will take place no earlier than May 17.