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EagleStr1ke
30-01-2014, 11:48 AM
So I was out imaging the Orion Nebula on the 15th of January this year. As I was checking the images after, I noticed a yellow streak on one of the pics. I've attached it so you can see. It was taken at 9:37 Sydney time. The image itself is crap because a gust of wind blew at the time. Using the Satellite Safari app, I checked to see if there were any satellites traveling through at the time, but nothing was even remotely close.

So the conclusion I've come to is that either it is a satellite that's not registered on the app (eg a classified spy satellite) or it's a shooting star.

Thoughts? (I'm bracing for the flood of UFO comments :))

ZeroID
30-01-2014, 01:06 PM
What's the exposure time per image ?

IanP
30-01-2014, 01:11 PM
Just a satellite, mate .. ;)

mithrandir
30-01-2014, 03:23 PM
You need to be fairly lucky to get an Orion shot that doesn't include a satellite. There are lots of geostationary sats at that declination. Stack enough frames and you'll hide them.

If you can say exactly when the shot was taken it's probably possible to work out which sat it is.

EagleStr1ke
30-01-2014, 05:31 PM
All frames had a 25s exposure time and this frame was taken at 9:37 so it does narrow it down a fair bit. Disappointed it wasn't a shooting star, but I've seen plenty with my eyes anyway. I didn't realise there were so many geostationary satellites in Orion.

el_draco
30-01-2014, 06:05 PM
Light from object is constant brightness. Highly likely its a sat.

Lee
30-01-2014, 06:43 PM
As Andrew said, it will be a geostationary satellite that your mount tracked past. Imaging anything along that declination will show them......

kinetic
30-01-2014, 07:13 PM
Too fast moving in a 25 sec frame Lee, I think, to be a geo.
More likely just a pesky polar or low orbit sat. The orientation of the track
would also reveal geo or non geo.
I have imaged geos with a modded webcam and they are much fainter and slower
than that.

Edit: see this thread (http://www.iceinspace.com.au/forum/showpost.php?p=670162)/post (http://www.iceinspace.com.au/forum/showpost.php?p=670162&postcount=10) for a similar image.
The speed of a typical polar satellite, passing through a similar exposure.

As for capturing geos: tracking off reveals them as a dot, stars trail...tracking on, they are almost impossible to image as they smear.)
You can calculate which band of declination you might expect the geos to be parked
over your location.

Steve

cometcatcher
30-01-2014, 09:17 PM
I agree with Steve, looks like a polar orbiting sat.

EagleStr1ke
30-01-2014, 09:52 PM
Yeah I think in 25s the scope wouldn't track past a geostationary satellite that fast so it's probably in another orbit. Well I'm glad the identification of the object is settled, thanks for all the help guys.