Perseid Meteor Shower — August 11th and 12th
In my experience, the highlight of every summer is the annual Perseid meteor shower, which this year peaks on the evening of August 11th and 12th. This is consistently the best meteor display of the year, and the fact that it occurs on typically mild nights makes it one of the most comfortable to watch.
Every year at this time, Earth passes through streams of debris that cover the path of the periodic comet Swift-Tuttle, which orbits the Sun on a long, looping path every 133 years. The comet was discovered in July 1862 by astronomers Lewis Swift and Horace Tuttle, and in 1866 Italian astronomer Giovanni Schiaparelli linked it to the Perseids. Subsequent research in ancient records mentions the shower for the first time in 36 AD.
The Perseids are active from mid-July to late August. Their name is derived from the point in the sky from which members of the Perseus constellation appear to emanate from the shower that rises into the northeastern sky after midnight.
The Perseids are fast and often leave persistent streaks of “trains” for several seconds after they flash across the sky. A single observer in a dark location can expect to see up to 100 Perseids at peak early morning on the 12th. The waxing Moon will set at 1:00 a.m. local time, giving you a few hours of quality darkness.
Return of the Planets
It’s been a while since our skies have been graced with bright planets, but that’s about to change. Late evening and early morning sky watchers will have an overview of a number of our fellow travelers through the Solar System.
For most of July and August, the action takes place in the morning sky, where you’ll find Saturn, Mars and Jupiter. Saturn rises first, rising to the southeastern horizon around midnight in mid-July and around 9:00 PM in mid-August. Saturn enters opposition, rising at sunset and setting at sunrise on September 8.
Saturn is approaching one of its equinoxes, which occurs every 15 years, and its famous rings are now tilted at a very slight angle to Earth. It appears as two spikes framing the planet’s disk.
Red Mars and bright Jupiter greet early risers in the morning twilight throughout July, but both will be well placed in the eastern sky for viewing by those looking to catch the Perseids. On the morning of August 14, the two planets will pass in close conjunction, only one-third of a degree apart.
Venus comes into action in mid-August, gradually appearing in the west as evening twilight begins. As we move into September, the dazzling planet will gradually pull in front of the Sun. With the onset of autumn, it climbs to a prominent position in the evening sky for the rest of the year.
Don’t forget the Milky Way!
The backdrop to all summer stargazing is a band of light that follows the star-studded Milky Way, the brightest parts of which bend majestically overhead as summer wanes. That amorphous glow you see from places in the dark sky is the combined light of some of the hundreds of billions of stars that accompany our sun in the great vortex of the cosmic spiral.
Three bright stars, Vega, Deneb, and Altair, form the Summer Triangle cluster, which is divided by some of the brightest star clouds in the galaxy. Binoculars or a small, low-powered telescope will begin to break these clouds into individual stars and star clusters, as well as show glowing emission nebulae.
There will be four full moons between the summer solstice and autumnal equinox. These will occur this Saturday (Strawberry Moon), July 21 (Full Buck Moon), August 19 (Full Sturgeon Moon) and September 17 (Harvest Moon).
Having four full moons in one season is unusual; there are usually only three. This leads to one definition of a “blue moon”, which according to a report in the 1937 edition of the Maine Farmer’s Almanac refers to the third full moon of the season as a “blue moon”. A more popular definition calls the second full moon in a calendar month a “blue moon”. The last time this happened was in August 2023.
Partial lunar eclipse — September 18
Summer has one last treat for us just before the autumnal equinox. The full moon on September 17 will look a little strange as Earth’s shadow blots out its northern polar regions in a small partial lunar eclipse. The middle eclipse occurs at 10:44 p.m. ET in Washington, when about eight percent of the moon will be covered.