Skywatch Line for Wednesday and Thursday, March 13 and 14, 2024, written by Alan French

This is Dudley Observatory’s Skywatch Line for Wednesday and Thursday, March 13 and 14, 2024, written by Alan French.

We changed to Daylight Saving Time last Sunday, so our sunrise and sunset times moved an hour later – our clocks “sprung ahead.” The Sun rises at 7:10 A.M. on Wednesday and sets at 7:00 P.M. On Thursday it rises at 7:08 and sets at 7:01. This Thursday has just under 20 ½ minutes more daylight than last Thursday. The coming Sunday is the first day we have more than 12 hours of daylight. Our longest day, June 20, will feature just over 15 hours 20 minutes of daylight.

The Moon was new on Sunday and is headed toward first quarter. On Wednesday night the crescent Moon and Jupiter will be a lovely sight in the western sky as darkness falls. At 7:45 P.M. the Moon will be 38 degrees above the horizon and bright Jupiter will be 3 degrees to its lower left. The Moon will be just over 17% sunlit. By 8:45 the Moon will be 27 ½ degrees high and the western sky will be completely free of twilight glow. The Moon will set at 11:33. The Moon will reach first quarter early Sunday.

Thursday night at 8:45 will find the Moon 27% sunlight and almost 51 degrees above the western horizon. Jupiter will be 14 degrees below the Moon. The Moon will be only 2 degrees below the Pleiades, or Seven Sisters. The crescent Moon and Pleiades will be a pretty sight in binoculars. The Moon will not set until 51 minutes past midnight.

Although the best lunar observing is often said to be around first and last quarter, by Thursday we are getting some prime time for exploring and enjoying the Moon with telescopes or steadily held binoculars, especially with the Moon riding high in the sky. Even Wednesday should provide some nice views. As always, look for mountain peaks and crater walls just over into darkness, catching the light of the rising Sun. It is fun to watch as more of the mountain or crater wall is slowly illuminated by sunlight, and as the Sun starts reaching crater floors. (I note a few features starting to catch sunlight and check each every few minutes.) There is also plenty to see just over into sunlight, where the shadows are long and detail well shown.

On Thursday there is late pass of the ISS (International Space Station). We see satellites because they are still up in sunlight when we are in the Earth’s shadow and darkness. Thursday’s pass of the ISS will move into the Earth’s shadow and fade from view when it is high in the sky. Its path will also take it close to the Moon.

Look for the ISS coming up from the west southwestern horizon at 8:25 P.M. By 8:56 it will be 23 degrees above the horizon, almost as high as Jupiter but 14 degrees to the planet’s west (left). The space station will be heading in the direction of the Moon. The ISS will pass within 1 ½ degrees (3 apparent lunar diameters) of the Moon just after 8:57 and will then pass through the Pleiades. Its path will then take it between Auriga and Perseus, and soon after, seconds before 8:58, it will move into the Earth’s shadow and fade from view, when 60 degrees above the horizon.