Stargazing and summer don’t always mix. The further north you are the longer the days and the shorter the nights, which makes astronomy tricky.
However, come August, the nights are beginning to darken, revealing the stupendous sight of the Milky Way in its seasonal arch across the night sky. Add a couple of giant planets reaching their brightest of the year, a pure “Blue Moon” and what promises to be the best meteor shower for years, and August 2021 is not a good time to stay inside, wherever you are.
Here’s everything you need to know about stargazing, planet-gazing and galaxy-gazing in August 2021:
1. Saturn at opposition
When: dusk on Monday, August 2, 2021
Where: rising in the east
The sixth planet from the Sun comes into “opposition” tonight, which is when Earth gets between it and the Sun. The “ringed wonder” is consequently at its biggest, brightest and best for all of 2021.
Rising at dusk in the east and setting at dawn in the west, any small telescope can be used to glimpse Saturn’s awe-inspiring ring pattern—and possibly its largest moon Titan, too. Look east at midnight and you’ll see Saturn rising in the constellation of Capricorn.
2. The Milky Way
When: after dark during the first week of August 2021
Where to look: southeast
In August the Milky Way arches overhead by midnight from mid-northern latitudes. This year, the first week of August—the week prior to New Moon—is arguably the best period of the entire year for viewing our galaxy from the northern hemisphere.
It’s a chance to see the densest part—that diffuse “milky” glow of billions of stars—arc across your night sky. For the best view get as far away as possible from light pollution.
3. Perseid meteor shower
When: early hours of Thursday, August 12, 2021 (and the nights either side)
The year’s best meteor shower strikes in the early hours today when about 100 shooting stars will occur in dark, moonless skies. You won’t realistically see that many, but if you get under reasonably dark country skies you’ll likely see 15-20 or so in a couple of hours.
Look at the night sky and keep looking! Put that smartphone away … it will distract you and completely ruin your dark-adapted eyes.
Be sure to look tomorrow night, too, because the actual peak is during the day, so which night is “best” is debatable and depends on your exact location. By far the best way to see lots of shooting stars is to go camping.
4. A crescent Moon and Venus
When: after sunset on Tuesday and Wednesday, August 10 and 11, 2021
Where: sinking in the west
Look low to the west just after sunset tonight and you’ll see a 5%-lit crescent Moon a mere 4° from the bright planet Venus. As it gets darker you’ll likely notice “Earthshine” illuminate the Moon’s dark limb—sunlight reflected from the Earth back on to the Moon.
You’ll need an unobstructed horizon. Come back on Wednesday and you’ll see a slightly brighter crescent Moon to the upper-left of Venus.
5. Jupiter at opposition
When: dusk on Thursday, 19 August, 2021
Where: rising in the east
It’s a great night to point a telescope at the “King of Planets” to glimpse its browny-orange stripes, though any pair of binoculars with 7x or 10x magnification will afford you easy views of the gas giant’s biggest moons Ganymede, Europa, Callisto and Io.
An almost full Moon will almost be in attendance.
6. Summer Triangle
When: July and August, 2021
Where: overhead around midnight
One of the anchors of the summer night sky, the “Summer Triangle” asterism (informal shape of stars) is something that can never be unseen once you’ve discovered it.
Comprising Deneb in Cygnus, bright Vega in Lyra and Altair in Aquila, the Summer Triangle has the the Milky Way streaming through it. To the left of a line between Deneb and Altair is the sparkling constellation of Delphinus, the dolphin, while just above Altair is Sagitta, the Arrow.
7. A full ‘Blue Moon’
When: dusk on Sunday, August 22, 2021
Where to look: rising in the east
Most people think that a “Blue Moon” is the second full Moon in the same month. Not so! The purest definition is actually the third of four full Moons in a single season, which occurs tonight.
At dusk and in the southeast will be the exquisite sight of a rising full “Sturgeon Moon,” but it won’t look blue. In fact, like any rising full Moon it will turn from orange to yellow as it rises into the night sky.
Times and dates given apply to mid-northern latitudes. For the most accurate location-specific information consult online planetariums like Stellarium and The Sky Live. Check planet-rise/planet-set, sunrise/sunset and moonrise/moonset times for where you are.
Wishing you clear skies and wide eyes.