Unusual Objects in Orion

[Shawn.Quinn]

Folks,

Monday night (2010.01.11) while imaging a region near Orion's belt with a DSLR, I captured an image of that included 'new' two very bright 'stars'. The odd thing about the 'stars' is that they only appear in 1 of 31 two minute frames captured over an our or so. Camera was on a tracker. 'Stars' were stationary with respect to the FOV. Iridium flares seem unlikely. At this point, the best explanation so far suggests up that I captured the strobe of a low flying aircraft (there is an small airport about 2 miles from the location where I captured the images). Equipment used to capture the images as follows:

Unmodified Canon 40D
TT320X Star Tracker
70-200mm Lens with Hutech LPS Filter (I live in a light polluted area)
Aperture was f/5.0 and focal length was set at 200mm.
ISO setting on the DSLR was 3200

Links to the three images:

http://www.flickr.com/photos/46558032@N04/4273568402/
http://www.flickr.com/photos/46558032@N04/4272824383/
http://www.flickr.com/photos/46558032@N04/4272824547/

Image 1 was acquired starting at about 9:28 PM EST
Image 2 (frame with bright 'stars') was acquired starting at about 9:30 PM EST
Image 3 was acquired starting at about 9:32 PM EST

Images were compressed to make more suitable for posting. No other image processing was performed external to the DSLR.

Any thoughts from the members of this board will be appreciated.

Shawn

[geckzilla]

I think you're right about it being an airplane. You can see the reflection of the strobes at the upper left of image 2 many times dimmer and can actually make out the shape of the bulb and the nearby compartment the bulbs are contained in:


Perhaps the strobes are similar to this: http://www.mcp.com.au/sting/newsletters ... trobes.jpg

Another question might be what are these small blips which seem to move against the background stars? There's two of them in this animation. What could they be?

[Chris Peterson]

Another question might be what are these small blips which seem to move against the background stars? There's two of them in this animation. What could they be?

The area of sky around Orion's belt coincides with the geostationary satellite band. It is very common when imaging this part of the sky to catch geostationary or geosynchronous satellites moving slowly against the background stars. With the exact time and location it is often possible to identify the specific satellites captured.

[Shawn.Quinn]

Folks, Thanks for the thoughts. Aircraft strobe certainly seems like the most likely explanation. Shawn