The Perseid radiant

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The Perseids 2009

The Perseid meteor shower is one of the best-known showers, with a peak of activity each year in mid-August. This year the maximum was expected to occur on 12th August between 17:30 and 20:00 UT (WAST = UT + 8hrs) with expected maximun rates of around 100 meteors per hour at the peak. Each meteor shower is named after the constellation from which the meteors all appear to originate, a position known as the radiant. The radiant for the Perseid shower is in the northern hemisphere constellation of Perseus (see image, left).

The parent body for the Perseid meteors is comet 109P Swift-Tuttle, named after its discovery by astronomers Lewis Swift and Horace Tuttle in 1862. The shower usually begins around July 17th and continues to be active until late August with a peak usually around August 12th. Perseid meteors are quite bright and fast, travelling at speeds of around 60 km/s through the atmosphere. Studies of the distribution of meteors in this shower show evidence for filamentary structure in the trail of debris left by the comet.

This year, the maximum was best viewed from places in and around the northern Pacific Ocean, including the extreme west of North America and and the extreme eastern Japan and China. Unfortunately for us, it was not visible directly from Australia, but there are telescopes in the north which we can still use to observe these kinds of events. One of these is a radio meteor detector situated at Jodrell Bank Observatory in the UK.

Next: Radio meteors and JBOMD