Skywatch Line for Wednesday and Thursday, October 15 and 16, 2025, written by Alan French

This is Dudley Observatory’s Skywatch Line for Wednesday and Thursday, October 15 and 16, 2025, written by Alan French.

The Sun rises at 7:09 A.M. on Wednesday and sets at 6:12 P.M. On Thursday it rises at 7:10 A.M. and sets at 6:11 P.M. Thursday lost 19 ¾ minutes of daylight compared to last Thursday.

The Moon reached last quarter on Monday, is moving toward new, rises well after midnight, and is high in the pre-dawn sky. On Wednesday morning at 6 A.M. look for a 32% sunlit crescent Moon high toward the east southeast. Jupiter will be almost 20 degrees above and right of the lunar crescent. Venus will be 6 degrees above the eastern horizon, rising to almost 12 degrees by 6:30.

Thursday morning at 6 A.M. will find a slenderer, 23% sunlit Moon, lower in the sky. The Moon will reach new on Tuesday, October 21. There are many dark, moonless evenings coming up.

Saturn is 35 degrees above the southeastern horizon at 9:00 P.M. Its rings are now tilted only 1 degree, so we have a poor, but different, view of the rings themselves. Saturn, however, is almost entirely in view, with little of the planet hidden by the thin rings. The narrow rings provide a nice opportunity to explore the planet’s atmosphere for details through the telescope, especially with larger instruments.

For seeing subtle details on the planets, experience matters, so regular observations of Saturn will gradually reveal more details. Saturn will also be moving higher in the early evening, which will also aid the views. The seeing, the steadiness of the view through our atmosphere, known as seeing, also varies. Frequent observing increases the chances of catching the nights of good seeing, where details stand out well and high magnifications can be used to advantage.

Observing when planets are highest increases the chances of good views. Saturn is due south and highest around 11:05 P.M. on these two nights, when it will be 43 ½ degrees above the horizon.

At 8 P.M. Cygnus, the Swan is high toward the south, almost overhead. Its brightest star Deneb, marking the tail of the Swan, in near and a little above the zenith. Looking from the south, the Swan stretches downward toward the horizon and toward the west (right). It is a beautiful area by eye under dark skies.

The star marking the head of the Swan, Albireo, is a lovely double star, perhaps the best-known double in the night sky. It is easy to find and is beautiful in any telescope, its two stars, separated by 35 arcseconds easy resolved. Jim Kaler describes them as “golden and blue.” Their contrasting colors are quite striking. Some observers find colors more easily seen by slightly defocusing the stars.