Stargazers prepare for shower of shooting stars as Leonid meteors make another visit

PUBLISHED : Monday, 09 November, 2009, 12:00am
UPDATED : Monday, 09 November, 2009, 12:00am

For those who missed the spectacular shower of shooting stars in 2001, another chance is coming up: the Leonid meteors are returning this month in their strongest form since eight years ago.

Nasa scientists predict as many as 500 meteors will streak across the sky in the hour before dawn on Wednesday next week. The best time will be about 5.40am, just before sunrise.

Local enthusiasts estimate Hongkongers will be able to spot 400 to 500 meteors as the earth comes close to the centre of a collection of debris trailing a comet. 'The shower could be half as strong as in 2001, but it would be much better than in the past few years,' a former vice-president of the Hong Kong Astronomical Society, Huey Pang, said.

Forecasters define a meteor storm as 1,000 or more meteors per hour. This year's Leonids would make 'a half-storm', California Institute of Technology astronomer Jeremie Vaubaillon said.

Viewers around the world spotted about 100 meteors an hour a year ago, while astronomers expect at least double that this year. Hongkongers usually saw fewer because of the bright surroundings, the weather or air pollution, Pang said.

About every 33 years, the Leonids enter a phase of enhanced activity that accompanies the return of their parent comet. The last such period occurred between 1998 and 2002 and the Leonids have been winding down ever since.

About 3,000 meteors swept by during the peak hour in 2001.

Scientists discovered recently that meteor bursts could 'lag behind' the cycle, Pang said. More than one collection of debris followed the comet and whenever one came close to the earth, heavier downpours of shooting stars could be seen. This meant it was possible people could catch a greater show of meteors during the 33-year gap and did not have to wait for a full cycle, he explained.

There would be more Leonid meteors this year because the earth came closer to the centre of one of the collections of debris, a former president of the Chinese University Astronomy Club, Chan Chun-lam, said.

The timing this year favoured observers in Asia over North America, but viewers in the Middle East could be in a better position than Hongkongers, he said.

People wanting to see the meteor shower did not need to take any equipment with them. They could look anywhere in the sky, but should focus more on the east, Pang and Chan suggested.

Darker places, such as Shek O, Clear Water Bay and Plover Cove Reservoir, were good spots, they said.