Anyone who looks up at the summer night sky for even a short time is likely to spot a few “shooting stars” darting across the sky.
The best meteor display of the summer comes during the second week of August during the annual Perseid meteor shower, which at its peak around the nights of August 11 and 12 is capable of producing 50 to 100 fast, bright meteors per hour for a year. single observer. Many flaming meteors with trains can be seen under good skies. 2024 will be a very good year for Perseid viewing, as the bright moonlight will not interfere.
The very first precursors of the Perseid swarm began to appear around July 25. At best you will only see a few per hour, but the numbers will start to increase during the second week of August. The last Perseid stragglers may not be seen until August 18.
In general, Earth experiences richer meteor activity in the second half of the year. And you’re more likely to see twice as many meteors per hour in the early evening compared to the evening hours. This is because in the pre-midnight hours we are on the “trailing” side of the Earth, due to our orbital motion through space.
So any meteorite particle generally needs to have an orbital velocity greater than that of the Earth to “catch” us. However, after midnight, when we face the “leading” side of the Earth, any particle that lies along the planet’s orbital path will enter the Earth’s atmosphere as a meteor. When such objects collide with our atmosphere at speeds of 11 to 72 km per second, their kinetic energy is quickly dissipated in the form of heat, light and ionization, creating short-lived streaks of light popularly known as “shooting stars”.
For more tips on photographing summer meteor showers, check out our guide to photographing meteors and meteor showers, and if you need imaging equipment, consider our best astrophotography cameras and best astrophotography lenses.
Meteoric supernumeraries
However, along with the Perseids, there are many other smaller meteors that are active at various times during July and August. While the hourly rates from these other meteor streams are only a fraction of the numbers produced by the Perseids, together they provide a wide variety of meteors of different colors, speeds, and trajectories. Summer meteors, which occasionally cross your line of sight, are especially noticeable between late July and the third week of August.
And between July 26 and August 21, there are no less than six different smaller displays that are active. These include Capricornids, Delta Aquarids, Piscis Australids, Alpha Capricornids, Iota Aquarids, and Kappa Cygnids.
The radiant points for five of these showers peak at about mid-high in the southern sky between 1 and 3:30 a.m. local daylight time. The radiant is the place in the sky where the paths of the members of the shower, if extended backward, would intersect near the star or constellation for which the shower is named. Many people think this is the best place to look for these meteors, but in reality the greatest numbers will be seen in the area of ​​the sky overhead and towards the south.
In addition to shower meteors, there are always apparently unrelated sporadic meteors that occur at an average rate of about seven per hour. The length of showering in days is somewhat arbitrary, since the beginning and end are gradual and indefinite.
The only equipment you will need is your eyes and a modest amount of patience.
As one longtime meteor enthusiast once noted, “Meteor watching is relaxing and enjoyable, potentially dramatic, and just plain fun!”
List of smaller showers
This first of our showers is Capricorn, which peaks on July 26th, although it extends from July 10th to August 15th. The radiant will reach its highest point in the south around 1:45 am. At most, only a few bright Capricorns will appear. in an hour, but this year those meteors will be handicapped by a bright waning moon shining brightly in the east-southeast sky.
Just two days to go until the Piscis Australids reach their peak on July 28 (July 15-August 30). The radiant crosses the meridian at 3:30 a.m. This is a minor current; only about eight members per hour will be visible to observers primarily in the southern hemisphere, where the radiant rises high in the sky. But the light from the nearby last quarter moon will hinder visibility.
Also on July 28 comes the peak of the Delta Aquarids, (July 12 – August 23). This shower has two radiants, indicating that we are seeing two distinct streams of celestial debris that produce faint, medium-velocity meteors burning in Earth’s atmosphere. This shower produces up to two or three dozen meteors per hour, and the radiant peaks highest in the south around 3 a.m. It can be seen.
Another weak shower is the Alpha Capricornids, which begins about July 3rd, peaks on July 31st, and ends on August 15th. Radiant is highest in the south around 1:00 AM. occasionally the fireball class – long trailing yellow meteors that can be quite spectacular. The good news: The moon has now shrunk to a thin crescent and will provide little, if any, conclusion to the search for these meteors.
The last minor shower before the Perseids is the Iota Aquarids, another double-radiant shower that has detectable numbers from July 15 to August 25. Peak activity is on August 6, and under good conditions only about six members per hour are observed; the radiants reach their highest point in the south at 2:45 am
After the Perseids, the Kappa Cygnidas are the last summer shower. The limits of this shower are August 3-28 with a peak on August 17. Although the maximum speed is only three per hour, the stream is classified as “slow moving and sometimes brilliant with blazing fireballs” and the careful observer can be handsomely rewarded for their time. The hours before midnight are the ones you choose for this shower. Radiant is north of the star Kappa Cygni and passes almost overhead at 10:30 in the evening. Unfortunately, an almost full moon lights up the sky for most of the night.
One month of summer meteors
We have included radiation maps here, courtesy of Yoshihiko Shigeno of the Nippon Meteor Society (NMS), which were created to make it easier to understand the distribution of visual meteor radiants. Each map is divided into ten-day intervals—late July, early August, and mid-August—and each meteor radiant location detected is marked with a small “x.”
Note that in late July the most active areas are in Capricornus, Aquarius and Perseus. By mid-August, the meteor radiants have become widely dispersed across Aquarius, while the Perseid radiant has become dominant.
SPACE.com will publish a comprehensive viewer’s guide to the upcoming Perseid swarm in the night sky on August 9. Stay tuned!