Summer sees the greatest number of “shooting stars”, with July being the peak. And every summer, skywatchers around the world look forward to observing the Perseid meteors – the “Old Faithful” of annual meteor shows. In the process, however, most viewers will overlook six relatively minor meteor showers that peak between July 26 and August 21 (three in July and three in August).
This year, unfortunately, an almost full moon will seriously hamper the observation of the Perseids. So why not take the opportunity to see the other six, all of whom will enjoy dark, moonless skies?
Radiants for most of them meteor showers will be concentrated in the southern part of the sky between approximately 1 a.m. and 4 a.m. local time. A radiant is the place in the sky where meteor paths, 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: meteors travel on parallel paths, but due to our point of view , meteors seem to shoot out from that particular spot in the sky.
Related: Guide to the 2022 meteor showers: Dates and viewing tips
So basically if you focus your observation here, you’re basically looking at the vanishing point or a void in the sky. Only the very occasional stationary meteor – the one that comes almost straight at you – can be seen here. In contrast, the greatest number of meteors will be seen perhaps 30 degrees from the radiant, in the general direction of the zenith, the point in the sky directly overhead. (Your fist held at arm’s length is about 10 degrees from the sky.)
But the majority of southern showers make it more likely that any “shooting star” seen in late July or early August appears to be coming from the south.
In addition to meteor showers, there are always sporadic ones. Before midnight they average two or three per hour, and just before dawn there may be as many as six or seven. The duration in days of meteor showers provided here is somewhat arbitrary, since the beginning and the end are gradual and indefinite.
Our information has been compiled from several sources, including the book “Meteor Showers — A Descriptive Catalog” (opens in a new tab) (Enslow, 1988), by Gary Kronk, and the International Meteor Organization’s 2022 meteor shower calendar (opens in a new tab).
This meteor shower peaks on July 26, although it runs from July 10 to August 15. With the July new moon just two days away and with the radiant peaking – about 30 degrees upwards – in the south at 1:40 a.m. local time, conditions are near ideal for searching 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 towards you. Only a few Capricornids will appear per hour, so most visible meteors will either be sporadic or members of another shower. A good way to separate the two is to imagine that the meteor’s path extends backward in the sky. Does it pass near Capricorn? If so, it is almost certainly a member of the shower.
This meteor shower runs from July 15 to August 10, peaking on July 28. Over the height of the Piscis Austrinids, the moon will be in a new phase, so you won’t have to worry about moonlight spoiling 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. Due to its low altitude, this meteor stream is best viewed from the Southern Hemisphere, where the radiant rises high in the sky and produces up to eight limbs 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 August 23. Aquarius (the water carrier) is depicted as carelessly carrying a pot of water for the water to spill out. The water jar is marked by a small triangle of pale stars, with a fourth star in its center. Interestingly, this shower has two radiants, suggesting that we are seeing two separate streams of celestial debris burning in earth’s atmosphere. One is located near the star Delta Aquarii, and the other is near the Water Pot configuration. Up to two dozen meteors per hour are delivered by this shower. Expect mostly faint, medium-velocity meteors with occasional much brighter events. The moon is still well out of the picture, and both radiants peak in the south around 3:40 a.m. at an altitude of about 40 degrees, meaning viewing conditions will be favorable throughout. of the morning.
Another weak Capricornus shower, which began around July 3, peaks the same night as the Delta Aquarids (July 30) and ends on August 15. The radiant is 40 degrees above the horizon at 1 a.m. Although few in number, Alpha Capricornids frequently produce slow-moving, bright yellow meteors (sometimes fireball-class) that can be quite spectacular.
This is the last minor shower before the Perseids and is another two-radiation shower with detectable limbs from July 15 to August 25. At peak activity on August 6, a bright waxing gibbous moon will set shortly after midnight, leaving the rest of the night dark for meteor viewing. At best, maybe six limbs per hour are seen in good condition. Radiants are at their highest – 40 degrees high in the south – at 2:15 a.m.
A waning gibbous moon, a day and a half past, will dominate the night sky from August 12-13 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 the north Perseus, rises in the evening and is nearly 70 degrees above the northern horizon at dawn. Without the disturbing effect of moonlight, observers would notice a crescendo in hourly rates averaging over 60 meteors per hour, although double that rate has been observed on occasion. Many blazing 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 to August 18.
Related: Perseid meteor shower 2022: when, where and how to see it
This is the last of the summer meteor showers, with the next significant display (the Orionids) will not arrive before the second half of October. The host Cygnus constellation (the Swan) is formed by a large figure of six stars commonly called the Northern Cross, the major axis of which runs lengthwise along the Milky Way. The limits of this shower are from August 3 to 25, peaking on August 17. But although the maximum rate is only three or four meteors per hour, this stream provides slow, sometimes bright fireballs, and a careful skywatcher can be well rewarded for the time spent. On peak night, the moon is a waning gibbous and doesn’t rise until around 10:30 p.m., but the hours before midnight are still the best time to see this downpour. At its highest, the star Kappa Cygni – from which these meteors seem to radiate – looms more than 75 degrees above the northern horizon at 10:15 p.m.
Joe Rao is an instructor and guest speaker at New York’s Hayden Planetarium (opens in a new tab). He writes on astronomy for natural history journal (opens in a new tab)the Farmers Almanac (opens in a new tab) and other publications. Follow us on twitter @Spacedotcom (opens in a new tab) and on Facebook (opens in a new tab).