Perseid meteors over Luzern, Switzerland ©right; Orest Shvadchak (Olympus Corp. E-M10 Mark III, 8mm, 1s, f/1.8, ISO1600) The Perseids are…
During this period, the moon reaches its full phase on Monday August 3rd. At this time, the moon is located opposite the sun and remains above the horizon all night long. This weekend the nearly full moon will set an hour prior to dawn, allowing a short but dark glimpse of the early August activity. By Thursday, the short, dark portion of night will have shifted to the evening sky in the hour following dusk.
Our friends at the IMO just released their annual meteor shower calendar for 2021: everything you need to know about 2021 meteor activity in 28 pages.
During this period, the moon reaches its first quarter phase on Monday July 27th. At this time, the moon is located 90 degrees east of the sun and sets near midnight. This weekend the more active morning sky will be totally free of interfering moonlight. As the week progresses though, only the few hours just prior to dawn will provide dark skies.
During this period, the moon reaches its new phase on Tuesday July 21st. At this time, the moon is located near the sun and is invisible at night. The moon will be located near the sun during this entire period; therefore, meteor observations can be held at any time of the night without lunar interference.
During this period, the moon reaches its last quarter phase on Monday July 13th. At this time, the moon is located 90 degrees west of the sun and rises near 0100 local daylight saving time (LDST). As the week progresses the waning crescent moon rises later in the morning with each passing night. This allows the window of dark skies to increase as the week progresses. The most active hours just prior to dawn will have slight interference from moonlight but one can overcome this simply facing in a direction where the moon is not visible within your field of view.
One good thing about a Perseid maximum with lunar interference is that it guarantees that two weeks prior that the Southern delta Aquariids (SDA) will peak under good conditions. Such is the case in 2020 when the last quarter moon will diminish the Perseid peak. The SDA's will peak on July 29th with a waxing gibbous moon setting just as the SDA radiant culminates in the southern sky.