Astronomers DO NOT say binoculars help with viewing the Perseids
The BBC was trying to do an article covering the Perseid meteor shower. Well they did a largely fair job on it, well almost.
No special equipment is required to watch the shower, which occurs when Earth passes through a stream of dusty debris from the comet Swift-Tuttle.
Yeah that's fine.
The meteors appear to come from a point called a "radiant" in the constellation of Perseus - hence the name Perseid.
Yup that's fine.
Astronomers say up to 100 meteors per hour are expected to streak across the sky during the shower's peak.
One person won't actually see 100 per hour, maybe three or four people looking at different parts of the sky might see closer to that sort of number.
But this year, light from the last quarter Moon will interfere significantly with the view.
Yes it will.
Astronomers say binoculars might help with viewing the spectacle, but will also restrict the view to a small part of the sky.
No sane astronomer would ever say that, you'll never see any meteors through binoculars. Don't bother even bringing binoculars with you, unless you plan to have a look at the Moon (best to do once you go outside so it doesn't ruin your dark adaption), or some of the open clusters in the region.
12th August 2009 14:53:22, 213 words, 730 views
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2 comments
You are certainly correct if one is just holding them at the ready, an look through once they spot a streak in the sky. That would be a waste of time indeed.
Let's assume lying on your back looking up you have a 150° field of view.
Let's be generous and say you're using binoculars that offer a massive 10° field of view.
Let's then assume there are 40 meteors per hour, which is a fairly realistic number for one person, heck even two people observing. In fact its the highest number per hour I've ever seen from the Perseids.
A pair of 10° binoculars offer only 0.44% the field of view. So for every 227 meteors that you'll spot with your eyes, 1 of those will pass through the field of the binoculars.
At 40 per hour, that means you'll see an average of one every five and a half hours.
If we're going to use a more regular pair of binoculars, say 10x50s, they offer about 6.5° field of view. That's about 0.19% the area you can see with the naked eye, so you'll need to be observing for an average of a little over 13 hours to spot one! Letting you see one meteor, and cutting out 526 other meteors doesn't sound like helping.
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