Posts tagged 'Gemini'

Observing Report 21st-22nd November 2008 (Shooting Unicorns)

Posted by on November 25th 2008 in Observing Reports

After the disappointment of being unable to observe the Leonid meteor shower earlier in the week due to rain and cloud, things were looking up (pardon the pun) for the alpha-Monocerotid shower on Friday night. The day had been cold and clear, and what wind there was had turned to a gentle breeze by 21:00.

I decided to make do without the hassle of setting up the mount, and made do with a static setup with the D50 on a fixed tripod, taking a variety of exposure-sets across a range of focal lengths. The MaxIm DL5 software on the lappy controlled the camera and downloaded the pics while I sat next to the tripod and watched events the good old-fashioned way. The only problems encountered were due to the cold, at -3C the D50's batteries don't perform well, only lasting for 200 shots before they needed to be warmed up or recharged. Having a couple of spare batteries is a godsend for such conditions. The cold didn't affect me, though - I was wrapped up in my Alpkit Filo, astrobreeks and Skee-Tex Original boots, nice and comfy.

The session began at about 22:00 and during the next four hours I observed 12 meteor trails (10 alpha-Monocerotids and 2 sporadics), of which 9 were fully or partly within the field of view of the camera, which took a grand total of 412 pictures.

At about 02:00 the clouds rolled in and ended the session. After clearing away the kit, I went through all of the photos, and guess what...  there's not even the slightest sign of any meteor trails on any of them, despite cranking up the enhancement levels to ridiculous levels! Typical.

So, I'm sorry, but there's no nice photo of the event to show to you. As a last resort, before binning all of the pics, I dubbed 77 of the 30-second frames together to make a small video showing Gemini rising, a few jet-tracks and the clouds that ended observations:

 

Get the Flash Player to see this content.

 

Clear skies tomorrow night

Posted by on December 12th 2007 in Astrostuff, Weather

Well, that's the weather forecast for here. Couple that with an ideal phase of the moon, and we have good conditions for standing outside, freezing our nuts off, looking for Geminid meteors. Let's hope that the weather holds for this shower... last month it was looking good for observing the Leonid shower until a front moved in and gave us 48 hours of 8/8 cloud-cover and heavy rain.

Here's an extract from the IMO Meteor Shower Calendar 2007:

One of the finest, and probably the most reliable, of the major annual showers presently observable. This year, the waxing crescent Moon will set by mid-evening across the globe on December 14 (the actual moonset timing is progressively later the further south you are), giving mostly dark skies for all observers, especially those in the northern hemisphere. The Geminid radiant culminates around 2h local time, but well north of the equator it rises around sunset, and is at a usable elevation from the local evening hours onwards, while in the southern hemisphere, the radiant appears only around local midnight or so. Even from more southerly sites, this is a splendid stream of often bright, medium-speed meteors, a rewarding sight for all watchers, whatever method they employ.

Here's some good advice from NASA for those hardy souls who intend to venture forth to see the lightshow:

  • Geminids meteors can be seen anytime after 10 p.m. local time, when the constellation Gemini is well above the horizon, but the best time to look is during the early morning hours between about 2 a.m. and dawn. That's when the local sky is pointing directly into the Geminid meteor stream.
  • The radiant of the Geminid shower is located near Castor, one of the two bright stars in Gemini (the other bright star is Pollux). To find the constellation at 2:00 a.m., go outside and face south. Castor and Pollux will appear approximately 45 degrees* above the horizon. Earlier in the evening, from 10:00 p.m. until midnight, Gemini will be about 30 degrees* above the horizon in the southeast.
  • You won't need binoculars or a telescope, the naked eye is usually best for seeing meteors which often streak more than 45 degrees across the sky. The field of view of most binoculars and telescopes is simply too narrow for good meteor observations.
  • Experienced meteor observers suggest the following viewing strategy: Dress warmly, as the mid-December nights are likely to be cold in the Northern hemisphere. Bring a reclining chair, or spread a thick blanket over a flat spot of ground. Lie down and look up somewhat toward the south. Meteors can appear in any part of the sky, although their trails will tend to point back toward the radiant.

(* this depends on your latitude)

Theoretically, the peak rate (ZHR) is predicted to be 120 meteors per hour, so it should be a good show.

Hopefully I'll be allowed out to catch some of the display on camera.

Related Posts Plugin for WordPress, Blogger...