You know summer is nearing its end when the best meteor shower of the year comes around.
The annual Perseid meteor shower, which typically produces roughly 100 meteors an hour at its peak in dark sky locations, is underway.
However, there’s a bit of bad news when it comes to this year’s display, and it has to do with the moon.
The shower runs from July 17 to Aug. 26, but peaks on the night of Aug. 12–13. Unfortunately, the moon will be 94 per cent illuminated. This means that only the brightest meteors will be visible.
But it’s not all bad news.
Because the Perseids produce so many meteors, and many of them tend to be bright, you can start seeking them out right away.
The Perseids occur as a result of Earth passing through the path of Comet 109P/Swift-Tuttle as it orbits the sun.
Try out this interactive map showing how Earth passes through the meteor shower:
Swift-Tuttle is pretty massive, comparatively speaking. Its nucleus is roughly 26 kilometres across; most comets are usually only a few metres. As a result, Swift-Tuttle sheds a lot of debris compared to other comets.
Most meteors you see in the sky are only about the size of a grain of sand. But sometimes they can be as large as a pebble. It’s these pebble-sized objects that produce fireballs, or extremely bright meteors. And that’s something that is associated with this particular meteor shower, which is very good news this year since the moon will be so bright.
But you don’t have to wait until the peak night; you can start looking within the coming days. The best thing to do is to get away from lights. That way, you’ll have a better chance of catching faint meteors.
And the best part about meteor showers is you don’t need binoculars or a telescope. Just lie on a lawn chair or blanket and look up. And be sure to put away that phone, as its light makes it harder for your eyes to adjust to the darkness, which can take 30 minutes or longer.
The best time to look is in the early hours of the morning, when Perseus is highest in the sky.
The new moon occurred on the night of July 31, so it will be steadily brightening as we head to the peak night of the Perseids. The good news is that, as it does brighten, it’s setting in the west as Perseus rises in the east. But it sets later each night, eventually gracing the southern sky around 11 p.m. local times on Aug. 12.
Your best night might be from Aug. 9 onward, as the frequency of meteors will increase the closer we get to the peak.
You might notice that, if you trace the meteors you see back to their point of origin in a particular area in the sky. That’s the constellation Perseus, from which the shower gets its name. But you don’t need to necessarily look in that direction. And be sure not to look away: you might miss them, as they’re fast. Perseids can travel at roughly 60 km/s.
And there’s a little bonus for night sky observing: On Aug. 9, Jupiter and the moon will be very close together in the southern sky.