Perseid meteors over Malta give stargazers a night to remember

The peak of the Perseid Meteor Shower has come and gone, but a good, long exposure has enabled us to keep a record this celestial passage.

Typical rates are about 80 meteors an hour, but in 2017 the Perseids were a little more difficult to see due to the presence of the moon, which is three-quarters full, leaving some 40 to 50 per hour being visible.

(C) James Bianchi

Earth passes through the path of Comet Swift-Tuttle from 17 July to 24 August with the shower’s peak — when Earth passes through the densest, dustiest area — occurring on 12 August. Comet Swift-Tuttle is the largest object known to repeatedly pass by Earth; its nucleus is about 26km wide. It last passed nearby Earth during its orbit around the sun in 1992, and the next time will be in 2126. But in the meantime, Earth passes through the dust and debris it leaves behind every year, creating the annual Perseid meteor shower.

(C) James Bianchi

What we’re actually seeing is the pieces of comet debris heat up as they enter the atmosphere and burn up in a bright burst of light, streaking a vivid path across the sky as they travel at 59km per second.

(C) James Bianchi

And… some space terminology here: “meteoroids” is what the debris is called when still in space. Once they enter the Earth’s atmosphere they are “meteors” and if they make it all the way down to Earth without burning up, they become “meteorites”.

But most of the meteors in the Perseids are much too small for that: they’re about the size of a grain of sand.