Skywatch Line for Wednesday and Thursday, July 9 and 10, 2025, written by Alan French

This is Dudley Observatory’s Skywatch Line for Wednesday and Thursday, July 9 and 10, 2025, written by Alan French.

The Sun rises at 5:26 A.M. on Wednesday and sets at 8:35 P.M. On Thursday it rises at 5:27 A.M. and sets at 8:34 P.M. Thursday gained 7 minutes, 19 seconds of daylight compared to last Thursday.

The Moon reached first quarter on Wednesday, July 2, and will reach full late Thursday afternoon, so a fat, waxing gibbous Moon will grace Wednesday night’s sky. The 99% illuminated Moon rises in the southwest at 8:18 P.M. on Wednesday. Look for it after the Sun sets as darkness falls. The Moon will be due south and highest at 29 minutes after midnight on Thursday morning. Its path is low across the southern sky and it will only be 18 ½ degrees high when it transits.

The full Moon will rise at 9:02 P.M. on Thursday in the southeast. Its path remains low in the south and it will be just under 21 degrees high when it transits at 1:23 Friday morning. After July 17 the sky before midnight will be free of moonlight.

There are five chances to see the ISS (International Space Station) on Wednesday and five chances to see it again on Thursday. Three are in the morning sky and two in the evening sky on each night.

The first pass Wednesday begins just after 12:38 A.M. low in the north northwest and the ISS will pass low across the northern horizon. It will pass below Polaris, 18 degrees above the horizon, just before 12:42, reaching magnitude -0.8. It will be passing through Perseus, low in the northeast, at 12:44, and will then head down to the horizon.

The second pass Wednesday begins at 2:16 A.M. in the northwest and the ISS will pass through the bowl of the Big Dipper beginning at 2:17:30 (HH:MM:SS). The space station will pass below Polaris just before 2:19 and will reach a maximum altitude of 17 degrees and magnitude -1.4. A little after 2:20 it will pass through Perseus low in the northeast and then head down to the eastern horizon.

The third morning pass Wednesday is a high one. The ISS will move up from the west northwestern horizon at 3:53 A.M. It will pass close to bright Vega in Lyra at 3:55:40 and then pass through Cygnus, the Swan high in the sky. It will reach a maximum altitude of 76 degrees and magnitude -3.9. Its downward path will take it through Pegasus and past Saturn in the southeast. It will vanish from view around 4:00.

The first evening pass on Wednesday will be high across the northwestern sky. Look for the ISS low in the west at 10:13 P.M. At 10:14 it will pass close to Denebola, which marks the tail of Leo, the Lion. At 10:15 the ISS will be approaching the Big Dipper and will soon pass through the it. At 10:16 it will pass through the handle of the Little Dipper and above Polaris and by 10:17 will pass above the “W” of Cassiopeia before disappearing in the northeast.

The final pass Wednesday is low across the northern sky. Look for the ISS low in the north northwest at 11:50 P.M. Just after 11:53 it will pass 18 degrees above the northern horizon and below Polaris. It will pass through the upper part of Perseus and disappear in the northeast.

The first pass Thursday morning is also low across the northern sky. Look for the ISS moving below the bowl of the Big Dipper at 1:28 A.M. At 1:30 it will pass below Polaris, reaching almost 20 degrees above the horizon and magnitude -1.1. Its path will take it through Perseus and down to the eastern horizon.

The second Thursday pass will be high and bright. The ISS will be rising along the northern side of Boötes by 3:04 A.M. and will pass south of the end of the Big Dipper’s handle at 3:05:30 (HH:MM:SS). It will then pass through Draco and above the Little Dipper, reaching its highest point, 65 degrees above the north northeastern horizon after passing through Cepheus. It will reach magnitude -3.4. The path will then take it past Cassieopeia and down to the east southeastern horizon.

Thursday’s third pass will be low across the southwestern horizon. Look for the space station low in the west just before 4:42 A.M. It will move low along the horizon and will shine at magnitude -2.2 when 17 degrees above the southwestern horizon at 4:44. It will move out of sight a little east of south just after 4:46.

The fourth Thursday pass will be a high evening pass. Look for the ISS moving up from the west southwestern horizon at rising 9:24 P.M. By 9:26 it will be passing north of bright Arcturus in Boötes. It will reach its highest point at 9:46:40 after passing Boötes, when 81 degrees above the north northwestern horizon and at magnitude -3.7.

The final pass Thursday is low across the northern sky. Look for the ISS low in the west northwest just after 11:01 P.M. It will pass below the front of the Big Dipper’s bowl at 11:03 and will reach its highest point, 22 degrees above the north northwestern just before 11:04, reaching magnitude -1.1. It will then pass below Polaris and vanish low in the northeast around 11:07.