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Canon DSLR Challenge | all galleries >> Challenge 108: Low and Wide : Hosted by Vikas Malhotra >> Exhibition : LOW AND WIDE > Perseid Meteor?
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13-AUG-2007 Jim H.

Perseid Meteor?

Muddy Mountain, Wyoming

This might be a Perseid meteor or it might be an "Iridium Flare". It was captured while trying to catch Perseids.

Canon EOS 20D
30s f/4.0 at 10.0mm iso1600 hide exif
Full EXIF Info
Date/Time13-Aug-2007 03:30:22
MakeCanon
ModelCanon EOS 20D
Flash UsedNo
Focal Length10 mm
Exposure Time30.00 sec
Aperturef/4
ISO Equivalent1600
Exposure Bias
White Balance
Metering Modepartial (6)
JPEG Quality
Exposure Programprogram (1)
Focus Distance

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Canon DSLR Challenge22-Dec-2007 11:46
Based entirely on the "look" of the streaks, I'm still betting on this being one or two Iridium satellites. Check out this site: http://www.satobs.org/iridium.html All of the photos they have seem to look similar to these with a "tapered" look to the streaks. I thought at one time I found a site that would let you enter coordinates and date ranges and it'd predict upcoming (or show back into the past) Iridium satellite flares. Looking for it again tonight, I only find a site that will show predictions for the immediate future. I'm sure it would be possible to back-calculate with the right program. Jim H.
Canon DSLR Challenge14-Dec-2007 18:04
I think I'm going to have to disagree with my father, since that event is about 4 months too late. -- Victor
Canon DSLR Challenge14-Dec-2007 08:27
My father says, "It was in the news here. It was spent booster rockets and other spent parts from a satellite that was launched from Cape Canaveral (I think). The debris fell into the Bay of Fundy, near New Brunswig, where it caused quite a sensation." -- Victor
Canon DSLR Challenge14-Dec-2007 02:31
I'm guessing it's a pair of planes and not an Iridium flare. Why? Because in both examples, the brightness is attenuated at both ends. That leaves a few possibilities. A single subject passed by several light sources, reflecting each in turn (darn near impossible), a single subject was rotating as it passed, offering the same reflecting surface periodically (unlikely for an Iridium satellite which would be less useful if rotating rapidly with respect to Earth), a single subject with multiple reflecting surfaces (the brightness would likely differ between the surfaces), multiple subject with the same reflectivity. I'm guessing it's the latter. Planes usually fly in lanes. It's possible you captured the same plane twice, with an attitude change in between. It's also possible you captured two planes. With EXIF data, it would be possible to calculate approximate speed (figure 20000 - 40000 feet and use known star positions at EXIF times to calculate distance traveled). If the resulting speed range is close to cruising speed of a plane, I think you captured a single plane. If it's far too slow, you captured two planes. A similar procedure could be used to rule in/out Iridium satellites, which go by at a known speed and altitude. If these were my pictures, I'd probably go through the work of doing all the calculations, but I think I'll be happy to leave it a mystery in this case. Oh, and presence of flashing lights would rule out a satellite, but absence would not rule out a plane or two. -- Victor
Canon DSLR Challenge12-Dec-2007 04:56
That's the full frame, Victor. I did see a lot of meteors that night, but what's visible to the eye is not necessarily visible on the sensor as you probably well know.

Looking through the pictures, I found another one close in the sequence, which has what may well be the same "flare" in a different part of the frame. The trajectory seems right. That would pretty well prove that it was an Iridium Flare and not a meteor.

Later frame:


Earlier frame:


There were two frames between those two and they show nothing on them. The shots were taken about 1.5 minutes apart. Each is a 30 second exposure. Too much of a coincidence for me!

I think we're seeing the same satellite in both frames as its orientation happens to reflect the sun at two times.

Jim H.


Canon DSLR Challenge12-Dec-2007 01:51
Hmmm. The date is certainly right for a Perseid, and the orientation is approximately right. However, I think it's a bit off. Seefor a chart of where the radiant was located for the Perseid shower of 2007. The orientation of the meteor seems to be about a month off (pointing toward July in the chart. The location of Mars confirms the date. If this is a crop (especially on the top) do you have an uncropped version available that may show more stars on the chart? -- Victor
Canon DSLR Challenge11-Dec-2007 23:34
That's actually the beginning of sunrise. I hadn't reset the clock in the camera for daylight saving time, so it's showing 03:30 but the actual time was 04:30. Just the very beginning of sunrise, I guess you might say :) Jim H.
Canon DSLR Challenge11-Dec-2007 23:27
Neat image - what's that light near the horizon on the left side? - Kelly