Anticipation is quite high for this year’s shooting stars, which peaks over a moonless weekend with projected rates of 90 to 120 meteors an hour.
Sky-watchers around the world are eagerly anticipating the arrival of the Perseid meteor shower, which will be at its best from August 12 to 13. Often one of the most impressive spectacles of its kind, the Perseid shower should be especially vivid this year because the sky will be moonless and dark during the peak.
The Perseids are actually visible from July 17 to August 24, although you’ll see only a few meteors an hour throughout most of that time period. The sky show spikes on the peak dates, with an expected average of 90 shooting stars an hour.
If you have clear skies, this deep darkness should deliver a great performance on the evening of August 12, with rates of up to 120 shootings stars an hour visible from countryside locales. Observers in eastern North America, Europe, and the Middle East should get the best seats for this meteor bonanza since the exact peak is expected to occur at 9 p.m. ET (01:00 UT).
While you can start hunting for Perseids as soon as it gets dark, the best viewing may be after local midnight and into the predawn hours of the 13th, when the skies will be at their darkest and your part of the globe will face the incoming meteor cloud. (See pictures of the Perseid meteor shower.)
Meteors will be visible even under bright suburban skies, but you can expect to see only a quarter to half as many shooting stars. No matter where you are, allow about half an hour for your eyes to adjust to the darkness before you start sky-watching in earnest.
The Perseids grace our skies when Earth ploughs through a cloud of fragments left behind by comet Swift-Tuttle, which last flew near the sun back in 1992. As the comet zooms in from the outer reaches of the solar system, its ices vaporize, and it releases debris ranging in size from sand grains to boulders. The particles get spread along the comet’s orbital path in such a way that Earth crosses the debris field around mid-August every year.
When that happens, the comet pieces slam into our atmosphere at speeds of around a hundred thousand miles an hour, causing the meteors to burn up and produce the brilliant streaks across the sky that we affectionately call shooting stars. (Here’s how scientists think we can create artificial meteor showers.)
Meteors will appear to radiate from the constellation Perseus, the mythical hero, which will rise after local midnight in the northeastern sky.
Despite their Greek namesake, the earliest known record of the Perseids appears in ancient Chinese texts, which mention awe-inspiring views of over a hundred meteors an hour as far back as A.D. 36.
Reported sightings continued throughout the centuries in many other cultures. In medieval Europe, devout Catholics referred to the phenomenon as the “tears of St. Lawrence,” since the yearly display coincided with the anniversary of the death of Lawrence the martyr. But astronomers didn’t recognize the link between the sky show and comets until the late 1800s.
What do you need.....
• DSLR body
• All of your batteries (and spares batteries; if you have an extended grip that holds AAs, bring it)
• Fast wide-angle prime or zoom lens (f2.8 or faster) with UV or skylight filter attached
• Heavy duty tripod
• Cable release or intervalometer (see below)
• A really comfortable outdoor reclining chair
• A good flashlight
• Lens-cleaning supplies
Why do I suggest a wide-angle lens and not a telephoto lens? Probability. The more sky you cover, the greater the likelihood of capturing a shooting star. You can cover twice as much sky with a 24 or 28mm lens than you can with a 50mm lens and the difference gets more dramatic the longer the lens gets. You may get lucky and pick just the right spot with a telephoto lens, but your odds of getting your perfect shot increase tremendously as you cover a greater area of sky.
The intervalometer is one item on the equipment list that you might not be familiar with. Think of it as a cable release on steroids. With a cable release, you’re shooting one frame at a time. With the intervalometer, you can program the length of the exposure, and the delay between shots. And you can program the number of frames you want to shoot. If you look on Ebay you can get a nice intervalometer for $30 or less.
1. Open and level the tripod.
2. Mount your camera and estimate where the best position and angle is for shooting.
3. An app for your smartphone called “Starglobe” is invaluable at finding the location of constellations in the night sky.
4. Set the shutter speed on “B” or Bulb.
5. Set your lenses focus control switch to “MANUAL” this will keep it from searching for infinity in the dark.
6. Set the aperture to wide open.
7. Attach your cable release or Intervalometer.
8. Set the focus to INFINITY by manually aligning the infinity mark on the lens with the focal length point on the barrel you are using.
9. Set the ISO to either 800 or 1600 to start (experiment from there).
10. If your camera has mirror lock-up, use it (this will reduce vibration caused by the mirror).
11. Verify your exposure settings (I shoot at 30 seconds to avoid star movement and spiraling).
12. Press the start or release button.
13. Check your first frame for focus by zooming in on the LCD display screen and adjust if necessary.