It is not by accident that my observations over the past few weeks were focussed on the Lyra constellation. I was doing this to familiarise myself with that area of the sky surrounding Lyra, primarily because this weekend is the peak of the Lyrids meteor shower - so called because the meteors would be observed radiating from this constellation.
The source of this meteor shower are particles of dust shed in the cometary tail generated by the periodic Comet C/1861 G1 Thatcher. The Lyrids normally yield an average of ten meteors per hour at its peak, so this is hardly the spectacular light show that you would see from the Perseids in August, the Leonids in November and the Geminids in December - with these you could probably see at least one meteor every minute. However, the Lybrids can produce meteors known as "Lyrid fireballs", which are significantly brighter and more spectacular than the thin streaks left by other meteor showers and may even leave behind smokey debris trails that last minutes.
I managed to capture my first ever fireball on camera last night:
The good news for those of you interested in meteor-hunting is that you don't need a telescope to do it. You just sit back in your lawn chair and look up to the sky with your MK I eyeballs. While meteors appear to radiate from one point in the sky (called the radiant), they can appear anywhere in the sky and at any time point in time - so a telescope would be virtually useless because you would have no idea where to point it.
The bad news is this also means you have no idea where to point the camera at and makes meteors very, very difficult to photograph well. So what I had to was to point the camera at about 45 degrees to one side of the radiant, set it at a wide field of view, have the camera automatically take time lapse photographs of 15-second exposures for two hours and hope for the best. That one photograph above was from over 200 images taken.
What's even more frustrating is that I managed to see at least one other fireball that was even more spectacular - it had much longer fire trail and lit the sky around it with a fiery green glow that lasted a full two seconds at least. Unfortunately, my camera was pointed in exactly the opposite direction during those two seconds.
Of course, taking time lapse photographs will also unintentionally capture every flying object in the sky, not just meteors. This includes the object below - not a Constitution-class Federation starship or a Klingon Bird or Prey, unfortunately, but a normal commercial passenger plane, judging from the regular patterns made by the red and yellow navigation lights and beacons.
Another challenge in meteor hunting is, of course, the British weather. Considerting this green and pleasant land has such horrid and unpleasant weather, I think it is nothing short of a miracle that this country can produce astronomers the likes of Isaac Newton and Edmond Halley. Last night was absolutely blanketed in cloud, the image below being typical of what conditions were like. Very pretty, of course, but very frustrating astronomically. I essentially only had a small windows of less than half an hour of a decent amount of clear sky to capture any images.
Nevertheless, last night was a good dress rehearsal for the big light show coming up in August - the Perseids. Here are a few tips on how you too can go meteor hunting then:
- Check for the peak time of the meteor shower.
- Meteors will tend to cluster around a single point in the sky called the radiant. Aim your camera toward this point, but not directly at it - about 45 degrees to one side will give you the highest chance of catching the most meteors and you'll be able to capture as much of the meteor trail as possible.
- Use a sturdy tripod and remote shutter trigger or shutter release cable, if available, to eliminate camera shake. You could also use the self-timer. Ideally, you should have a camera or camera control computer software that would allow time lapse photographs to be taken automatically.
- Use the manual mode on the camera to have full control
- Set to a wide angle setting - this increases your likelihood of success. The wider your lens, the more sky you'll get in your photo and the higher the chance you'll catch a shooting star. But not too wide though - otherwise your meteor streak will appear too small and quite unimpressive.
- Use manual focus. Focusing on stars can be difficult in a dim viewfinder, so set the focus by focussing on a bright star such as Vega or Arcturus, or just set it to infinity.
- Set F stop settings just short of wide open
- Set cameras for long shutter times but not too long, to avoid star streaking and CCD noise. Lots of short 5-15 second exposures might do better than, say, a single maximum exposure, since long exposures with digital cameras result in noisy images My shot above was taken using 15-second exposures.
- Meteors are impossible to predict, and it takes a great deal of luck to capture them on digital film. Don't be discouraged if you take a hundred photos of the empty sky - if you keep trying, eventually you'll catch that one beautiful falling star!
- Bring a lawn chair and sit back to enjoy the show.
