Comet?

[Karls48 (Karl)]

Comet?
This morning about 3AM I woke up and notice that sky is clear (that does not happen often lately). I got Mintron camera with 50mm F1.8 lens set up looking out of bedroom window, pointing about 190 deg. and about 40 deg elevation. I switch it on and went back to sleep. In the morning when I look on image of star trails I noticed that one, very faint, trail is crossing other trail. What is it? It is not a satellite or meteor. I can not find any comet with my software in that region of sky
Karl48

[ving (David)]

interesting pic karl. i see the crossing one that you mentioned and have nfi what it is. it could very well be an asteriod, or maybe a geostationary satelite...
interesting.
I am picking asteriod

[[1ponders] (Paul)]

Any idea of the RA DEC coords at all carl? 3 am 190 deg and 40 up could be anywhere depending on where you are in Australia.

[Karls48 (Karl)]

No idea, I woke up to go to loo and saw clear sky so I click the button and went to sleep. I keep camara setup in hope I will catch one night real big fireball meteor and also for testing. It never come to my mind that I will get someting else interesting, beside satelites and meteors.
Image was taken from 33.45.43 S 150.49.28 E, 25 frames stacked 350x. Time 03.31.35, total exposure 1421sec.
I will be watching for it tonight, but it is cloudy

[Karls48 (Karl)]

Working back, I think that bright star in the image is Miaplacidus

[cometcatcher (Kevin)]

Only just spotted this thread..

Why do you think it's not a satellite? There's no way of judging the relative speed of a star trail compared to a satellite trail on a still image. My bets would be a low orbit satellite. The taper in brightness of the trail would suggest Earth shadow involvement.

It's not a geostationary satellite Ving. They would only show as a faint dot with a 50mmm lens.

[Karls48 (Karl)]

Hi Kevin
No, it is not satelite. Camera was set up for 64x frame integration. It increases magnitude that camera can see for given lens size by about 1.5 Mag, but any fast moving object will show broken line trail.
Karl

[cometcatcher (Kevin)]

I'm confused how your capture software works. 64x is about 1.25 seconds per frame. I thought if it's stacking every single frame integration consecutively there shouldn't be a gap betwen frames on any speed object unless it's dropping frames. That's if the capture rate is set to match the integration time.

For example in these two frames, one is just a a single 64x frame integration, the other is 13 64x frames with the capture card set to capture every frame.

How does your software work? I thought it would be similar to create star trails?

[Astroman (Andrew Wall)]

is there a way to do an animation of the sequence, that should give a fair idea on what it might be. Chances are it could be a geostationary satellite to, moves with stars (or earth)

[Karls48 (Karl)]

You are right, my software (AstroVideo) works same as yours. Image I have posted was taken with 25 frames 600x, fixed. Meaning that every frame is superimposed on previous one But frame integration is also done by camera itself. I can set camera for no integration 0.1 LUX sensitivity to 128x(about 2.5sec) 0.001 LUX. Advantage is increase in sensitivity, ( you can see up to 3 mag more for given lens size) disavantage is that it works well only for stationery or very slow moving objects, like stars) . Anything that moves fast ( meteors, aircraft or satelites leaves faint broken trail. It is because pixels on CCD don't receive full charge as image moves from one pixel to other one, because interation have not finised. When I use this camera with 6" telescope I can see stars that I would see with 12" scope. But as I said, it got advatage and disadvantages. If I move scope I have to wait for 2 sec until image settles down.
Karl

[Karls48 (Karl)]

Hi Andrew
No, to my knowledge there is not. Image was saved as single FIT file and I cannot see how it could be reconstructed to singe frames
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