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Important notices

2013 Perseid Meteor Shower

     The Perseid Meteor Shower, associated with the Comet Swift-Tuttle, is among the most spectacular meteor showers throughout the year. Its maximum occurs around the 12th to 13th August every year. The  number of meteors emerges from Perseids is relatively stable. Under favourable observing conditions, as many as 100 meteors per hour can be observed during the maximum (ZHR=100)*.

     On 12th August this year, the radiant of Perseid will rise at about 9pm. As  the radiant rises, there will be more observable meteors in late night.  Since it is the 6th day of a lunar month, the Moon will set at around 10pm.  Hence, it will not affect observation of the meteor shower.  Observers should have not much difficulty in watching the shooting stars provided that they are patient and the weather is fine. Moreover, 13th August 2013 is the Qixi festival, which falls on the seventh evening of the seventh lunar month. In Chinese mythology, the Cowherd and the Weaver Maid meet in Heaven on that day. Would you look at the stars Altair and Vega ,which represent the Cowherd and the Weaver Maid while you are waiting for the meteors?

Information on the predicted maximum of the Perseids is as follows:

Hong Kong Local Time Observing condition
Zenithal Hourly Rate
August 13 (00:15 - 04:45)  



(source: International Meteor Organization)

Here are some tips for watching the Perseids:

  1. Based on the data of 2012, the number of meteors on the day before and after the maximum could vary as much as 50%. Therefore, it would be ideal for observation to be conducted at the night of maximum. Despite the recent advances in forecast theory, there may still be high variance in terms of observation time and quantity of meteors. Therefore, it may not be possible to guarantee the best time for observation.

   2. The radiant of Perseus rises from the horizon in the northeast at about 9 p.m. on that day.  Then It is visible during the whole night afterward.

   3. Although the radiant of the meteor shower is located in the constellation Perseus, the meteors may not necessarily emerge from the sky zone near the the radiant. Therefore, an ideal observation should take place at a site with unobstructed view, especially in the northeast.

   4.  One can definitely view more meteors in the countryside, with the night sky dimly lit.  However, the thoughts of travelling time to spend, unstable weather, work or school commitments the next day will deter one from doing so.  An open space near your living place (e.g. podium garden) with unobstructed view and no direct lights from the surrounding area will also be an ideal place for stargazing.

   5. Basically, the meteor can be appreciated by naked eyes and no telescope is required. You should bring along with you a star-map, a red light torch, a deckchair and a sleeping bag or mat.

   6. You may capture the image of Perseids with a camera. Basic equipment includes a camera with long time exposure function ('Bulb' shutter). Camera lens should be set to infinity with maximum aperture. Then point the camera to Perseus or neighbouring constellations for a 5-minute exposure time at an ISO value higher than 400 and try your luck. Please avoid using flash light or white light for illumination as it may seriously affect other observers.

@* ZHR (Zenithal Hourly Rate) is the hypothetical hourly rate of meteors observable under an extremely dark and wide sky with the radiant located in the zenith. As it is only an ideal rate, in practice, observed rates will be definitely lower than the derived ZHR.