Ephemeris: 08/24/2023 – The Moon will pass in front of the star Antares tonight

This is Ephemeris for Thursday, August 24th. Today the Sun will be up for 13 hours and 38 minutes, setting at 8:33, and it will rise tomorrow at 6:56. The Moon, at first quarter today, will set at 12:11 tomorrow morning. | Tonight the Moon is going to pass in front of the bright reddish star in Antares in Scorpius scorpion. The event is called an occultation, and it is the only one of the monthly occultations which we’re going to be able to see in this series that began last month and will extend to August 2028. Antares will disappear at the lower left edge of the dark or night part of the Moon at approximately 10:28 pm* this evening, and it’ll stay hidden until 11:32 pm* when it will pop out on the lower right edge of the bright part of the Moon. Start looking for Antares early, probably with binoculars, because the Moon will be quite bright and might overpower Antares when viewed by the naked eye. Hoping for clear skies tonight.

*The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT –4 hours). They may be different for your location. For other locations a planetarium computer app like Stellarium can be used to graphically predict occultation timings within a few minutes. Check your planetarium app, and set it to use Topocentric coordinates. In Stellarium, the selection is in the Configuration window, Tools tab. Check everything under Topocentric coordinates. That way the position of the Moon in the sky will be based on the chosen location, rather than the center of the Earth.

Addendum

A time-lapse prediction of the occultation of Antares by the Moon based on Stellarium imagery. In the actual occultation Antares will wink out and on suddenly. Antares is a double star, with a 5th magnitude companion. It should wink out and in 9 seconds before the main first magnitude star.

World map showing the area where the occultation of Antares can be visible. It is the area bounded by the white line, the red dotted line and the floppy figure 8 is the area where the occultation is visible. The red line shows that the area near that part of the line is where the occultation occurs during daylight the solid white line on the bottom encloses there is where the occultation will be seen at night. Michigan is close to that cyan line and so the occultation will occur near moonset. Credit: Occult 4 app.