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View Full Version : Australian "meteorite", revisited



Evan
2004-Dec-08, 08:54 AM
On the home page of this site the BA says:


... This is being discussed on SlashDot as well, and one person came to the conclusion that it's a bug flying across the image. It's close to the camera, so it's out of focus. The camera flash lit the bug at the end of the exposure, creating the burst of light. It happens to lie coincidentally near the lamp, but has nothing to do with it. I concur; this is the most likely explanation.

Excuse me. A bug flying across the image? Just how so? Lit by flash at the end of the exposure? Why? If I was taking pictures of the background clouds (the purported reason for the pictures) I would not be using flash. Also, the exposure would not be long enough for a bug to fly across nearly the entire frame during the exposure.

I do not believe it is a meteor but the above explanation doesn't convince either.

kucharek
2004-Dec-08, 09:22 AM
The image data (EXIF) clearly shows that the flash was fired. The camera was in automatic mode, 1/20s, F5.6, don't know the ISO-setting. As it was a little bit dim, the camera decided to add the flash. The camera doesn't knows that it doesn't help.
Now, if the bug is pretty close (it must be to be so much lighted by the flash), it is no problem to cross half of the image in 1/20s. IIRC, the flash fires at the beginning of the exposure. So, a bug was flying towards the camera. The flash fired. The bug continued to the upper left corner of the image. The bug hadn't to fly hundreds of meters. Maybe just one.

Harald

BTW, this is the third thread on the subject. Maybe we continue on
http://www.badastronomy.com/phpBB/viewtopic.php?t=17877
or
http://www.badastronomy.com/phpBB/viewtopic.php?t=18156
I'd prefer the latter, as it is more about the new images on APOD.

Harald

Evan
2004-Dec-08, 03:55 PM
I don't know of any bugs that can fly 10 to 20 meters per second.

Meteora
2004-Dec-08, 04:19 PM
I don't know of any bugs that can fly 10 to 20 meters per second.

Deer flies.

I think....

I know they have absolutely no problem keeping up with a bicyclist going about 8 m/s. Seems like I once read that they can fly up to about 25 m/s. :o

JustAGuy
2004-Dec-08, 06:29 PM
I dunno guys, there's a few things about this that don't add up. First, the "explosion" depicted is absolutely huge, if we believe it occured at the lamp. Look in front of that lamp, a bit down. Yup, that's a car. And it's both smaller than the "explosion" and quite a bit closer. Also note that this huge flash has no reflection on the water.

Now, absolutely no one saw this. No one saw the light, no one saw any smoke, no one heard anything. The subject of the picture is a port, which one can assume is not deserted. This image was only discovered to be interesting after the fact when the photographer was reviewing his work.

I'm not sure we can conclusively say what it was, but we can say it sure looks like X. And X, in my opinion, is a bug. There was a good comparison pic posted on the /. thread that demonstrates how a bug can leave a dark streak (here (http://www.ufotheatre.com/rods/proof1.jpg)).

However, it doesn't exactly match, but I'm willing to leave it at that unless we decide to spend a lot of time photographing bugs to build up our body of data, since bugs aren't too terribly exciting. There's no need to invoke incredible explanations like meters, WIMPs, or what have you here, when a bug matches the data as well as those or even better.