08/07/2018 – Ephemeris – The source of the Perseids
Ephemeris for Tuesday, August 7th. The Sun rises at 6:35. It’ll be up for 14 hours and 24 minutes, setting at 9:00. The Moon, 3 days past last quarter, will rise at 3:18 tomorrow morning.
The Perseid meteor shower will reach its peak Sunday night and Monday morning, less than a week from now. The meteor shower is caused by tiny particles shed by the comet 109P/Swift-Tuttle on past trips through the inner solar system. The 109P means it was recognized as the 109th comet to have seen to return to the vicinity of the Sun to be rediscovered in 1992. Lewis Swift and Horace Tuttle first discovered the comet independently in 1862. The orbit of the comet fit the orbits of the meteoroids that produce the Perseid meteor shower each year. The comet will return in 2126 after retreating to 51 times the Earth’s distance from the Sun, deep in the Kuiper belt, leaving behind a trail of meteoroids.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum

The passage of 109P/Comet Swift-Tuttle through the inner solar system November 1, 1992 to January 30, 1993. The meteoroids shed by the comet on its numerous trips close to the Sun lie close to that orbit. Note that its orbit intersects with the Earth’s orbit. That’s where the Earth will be around August 12-13 every year. Click on the image to enlarge. Created using my LookingUp program.