Summertime sees the greatest number of "shooting stars," with July being the peak. And every summer, skywatchers all over the world look forward to observing the Perseid meteors — the "Old Faithful" of the annual meteor displays. In the process, however, most viewers will overlook six relatively minor meteor showers that peak between July 26 and Aug. 21 (three in July and three in August).
The radiants for most of these meteor showers will be concentrated in the southern part of the sky between roughly 1 a.m. and 4 a.m. local time. A radiant is the place in the sky where the paths of meteors, if extended backward, would intersect from a particular constellation. Many people are misled into thinking that this is the best place to look for these meteors, but in reality, the radiant is an optical illusion: The meteors are traveling on parallel paths, but due to our perspective, the meteors appear to be darting from this particular spot in the sky.
So, in essence, if you concentrate your viewing here, you'll be looking basically at the vanishing point or a void in the sky. Only the very occasional stationary meteor — one that is coming nearly straight at you — can be seen here. In contrast, the greatest number of meteors will be seen perhaps 30 degrees away from the radiant, in the general direction of the zenith, the point in the sky directly overhead. (Your fist held at arm's length corresponds to roughly 10 degrees of the sky.)
But the majority of southern showers do make it more likely that any "shooting star" seen in late July or early August will appear to be coming from the south.
In addition to the shower meteors, there are always sporadic ones. Before midnight, these average two or three per hour, and just before dawn, there are perhaps as many as six or seven. The duration in days of the meteor showers provided here is somewhat arbitrary, since the beginning and end are gradual and indefinite.
Our information was compiled from several sources — most notably, the book "Meteor Showers — A Descriptive Catalog" (opens in new tab) (Enslow, 1988), by Gary Kronk, and the International Meteor Organization's 2022 Meteor Shower Calendar (opens in new tab).
This meteor shower peaks on July 26, though it extends from July 10 to Aug. 15. With the July new moon only two days away and the radiant reaching its highest point — about 30 degrees up — in the south at 1:40 a.m. local daylight time, conditions are nearly ideal to look for these bright meteors. The stars of Capricornus (the Sea Goat) form a roughly triangular figure, which may suggest an inverted cocked hat, or perhaps a stingray swimming directly toward you. Only a few Capricornids will appear per hour, so most of the visible meteors will be either sporadic or members of another shower. A good way to separate the two is to imagine the meteor's path as being extended backward on the sky. Does it pass near Capricornus? If so, it is almost certainly a shower member.
This meteor shower extends from July 15 to Aug. 10, peaking on July 28. During the height of the Piscis Austrinids, the moon will be in new phase, so you won't have to worry about moonlight ruining the view. The radiant is not far from the first-magnitude star Fomalhaut, which appears quite low — about 20 degrees, or two fists, above the southern horizon — at 3:15 a.m. Because of its low altitude, this meteor stream is best viewed from the Southern Hemisphere, where the radiant climbs high into the sky and produces up to eight members per hour.
July 30 marks the peak of the Delta Aquarids, the most prolific of the six minor showers, which runs from July 12 to Aug. 23. Aquarius (the Water Carrier) is pictured as carelessly carrying a water jar so that water is spilling out. The water jar is marked by a little triangle of faint stars, with a fourth star at its center. Interestingly, this shower has two radiants, suggesting that we're seeing two distinct streams of celestial debris burning up in Earth's atmosphere. One is located near the star Delta Aquarii, and the other is near the water jar configuration. As many as two dozen meteors per hour are provided by this shower. Expect chiefly faint, medium-speed meteors with occasional significantly brighter events. The moon is still well out of the picture, and both radiants reach their highest point in the south at around 3:40 a.m. at an altitude of roughly 40 degrees, meaning viewing circumstances will be favorable throughout the morning.
Another weak shower from Capricornus, which began about July 3, peaks the same night as the Delta Aquarids (July 30) and ends on Aug. 15. The radiant is 40 degrees above the horizon at 1 a.m. Though few in number, the Alpha Capricornids frequently produce slow and bright (sometimes fireball-class) yellow meteors that can be quite spectacular.
This is the last minor shower before the Perseids and is another two-radiant shower having detectable members from July 15 to Aug. 25. At peak activity on Aug. 6, a bright waxing gibbous moon will set shortly after midnight, leaving the rest of the night dark for meteor watching. At best, perhaps six members per hour are seen under good conditions. The radiants are at their highest — 40 degrees high in the south — at 2:15 a.m.
A waning gibbous moon, one and a half days past full, will dominate the overnight skies of Aug. 12 to 13 to spoil this year's annual performance of the Perseid meteor shower. The radiant, which is not far from the famous Double Star Cluster in northern Perseus, rises in the evening and is nearly 70 degrees above the northern horizon at the break of dawn. If not for the hampering effect of moonlight, observers would notice a crescendo in hourly rates averaging more than 60 meteors per hour, though double this rate has been seen on occasion. Many flaring meteors with trains are seen under dark skies, but unfortunately, only the brightest of them will be visible in 2022. This shower normally extends from July 25 through Aug. 18.
This is the last of the summer meteor showers, with the next significant display (the Orionids) not coming until the latter half of October. The host constellation Cygnus (the Swan) is formed by a large figure of six stars popularly called the Northern Cross, the long axis of which lies lengthwise along the Milky Way. The limits for this shower run from Aug. 3 to 25, with the peak occurring Aug. 17. But although the maximum rate is only three or four meteors per hour, this stream does provide slow-moving, sometimes brilliant flaring fireballs, and a careful skywatcher may be nicely rewarded for the time spent. On peak night, the moon is a waning gibbous and does not rise until around 10:30 p.m., but the hours before midnight are still the best time to view this shower. At its highest, the star Kappa Cygni — from where these meteors appear to radiate — stands more than 75 degrees above the northern horizon at 10:15 p.m.
Joe Rao serves as an instructor and guest lecturer at New York's Hayden Planetarium (opens in new tab). He writes about astronomy for Natural History magazine (opens in new tab), the Farmers' Almanac (opens in new tab) and other publications. Follow us on Twitter @Spacedotcom (opens in new tab) and on Facebook (opens in new tab).