|
The Perseid Meteor Shower has over the last two nights put on a magnificent display in the skies over the UK with up to two meteors a minute seen at its peak on the 12th. Observing conditions for the shower were nearly perfect without the Moon or cloud to spoil the show. The Perseids, which are named because they appear to emanate from the constellation of Perseus, are one of the most reliable of the annual meteor showers usually having at least 60 meteors per hour. The meteors themselves are formed by light produced when dust particles burn-up as they enter the atmosphere at speeds of 135,000 mph. Each year the Perseid shower occurs when the Earth passes through a stream of dusty debris produced by the comet Swift-Tuttle. Dust particles in the stream were once part of the icy nucleus of the comet but were carried away into space by the gas that is produced when the comet's ice is heated by the Sun.
The Perseids are often striking bright blue-white meteors and because they occur in August each year they are usually easily observed. The shower was first recorded in 36AD by Chinese astronomers and in medieval England were known as "the burning tears of St Lawrence" since they fell close to the saint's feast day.
Although the number of meteors within the Perseids remains relatively constant up to 300 meteors per hour were seen in 1993. This increase is thought to be because the source comet of the dust Swift-Tuttle passed close to the Sun in late 1992. The Earth encountered the denser region of dust produced by the comet the next year. Comet Swift-Tuttle is around 6-miles across and takes around 135 years to orbit the Sun.
More info: The Perseids
|
