Meteor shower 'set to return'

The Leonid meteors make a return appearance in the night sky this week as the Earth ploughs through a comet’s dust trail.

Although nothing like as spectacular as last year, the meteor shower should still reward patient night owls.

Experts predict that up to 100 Leonid shooting stars could be seen streaking across the sky every hour.

However, light from the moon will make the meteors hard to spot until about Wednesday.

Robin Scagell, from the Society for Popular Astronomy, said: “It is unlikely to produce any real fireworks, but there is always a chance that there may be a sudden burst of activity, and the dedicated meteor watchers will be out there looking anyway.

“One of the nice things about meteor watching is that its very easy to make useful scientific measurements. Just by measuring the rate of the meteors you can get an idea of the amount of dust at this point in the comet’s orbit.”

Meteors are tiny particles shed by comets as they swing round the Sun. When they hit the Earth’s atmosphere at 40 miles per second they burn up, leaving the glowing trails known as shooting stars.

The Leonids, seen every November, are produced by the comet Tempel-Tuttle which measures about 2.5 miles across.

Tempel-Tuttle makes one orbit of the Sun every 33 years. As it nears the Sun, part of its icy surface burns off to produce a shower of debris.

The Leonids are named after the constellation of Leo, the Lion. If you trace all the meteor trails backwards, they meet at a point just above Leo in the north-east.

As the Earth turns, the “radiant” point rises higher in the sky. For this reason the Leonids cannot be seen before 11pm and the best time to spot them is about 3am or 4am.

Sometimes meteor showers reach intense levels, when they are known as storms.

Last year the Leonids produced storm displays of up to 3,000 meteors per hour over Europe.