Saturn and the ISS

[meltaxa]

Captured 6:20pm 6th September, 2022 over the Gold Coast, Queensland.

Celestron 9.25; ZWO ASI224MC; IR/Cut filter.
Firecapture: 1 ms, 411 gain.

In hindsight, I should've had gain around 200. I was so rushed to setup in time that I didn't check my notes, which had that written down. Failure is my teacher. Lesson learnt.

I chose not to produce a composite (ie. capture Saturn on it's own and then blend that in with the ISS capture) out of personal preference. I'd rather use the data in the single capture and tease out the exposure using gamma. As I do to bring back proms from solar h-alpha captures. The result seen is the raw frames from the SER file converted to an animated gif.

[Mickoid]

Dennis, great work and planning to capture what was probably all over within a fraction of a second. I can imagine you would have been hoping you got the framing right because you were only going to get one chance at this. Well done. I understand what you mean by not fiddling with the footage and keeping it 'pure' so to speak. Thanks for sharing. :thumbsup:

[rustigsmed]

great grab dennis

[EpickCrom]

Great result Dennis:thumbsup:

[meltaxa]

The capture was indeed over in a fraction of a second. That gif animation is a slow motion because it pauses 0.01s between frames as a minimum.

It's nerve wracking watching the ISS, thinking it will miss too. My spotter said it appeared to be a bullseye transit with the naked eye, but the capture said otherwise. I'm grateful that I was within the vicinity for the ISS to be within the frame. So many variables in play for this to go sideways (pun intended). :D

[Dennis]

Brilliant work Dennis.:):thumbsup:

Cheers

Dennis

[Dave882]

Great catch! What program are you using to predict upcoming transits?

[meltaxa]

Ed Morana's ISS Transit Prediction (for Android phones only) to pinpoint a location for planetary transits. I found that Morana's app would change the precise location prediction (-/+50m) every time I ran it, despite the model and latest prediction files not changing. I had to make a best guess on where I should be exactly. It seems to be losing its reputation for accuracy. Unfortunately, it was the only tool I could find that does planetary transit predictions otherwise, you would have to correlate information gathered from various other sites (below) to plan it.

To confirm the sightings, trajectory and rough locations see:

spotthestation.nasa.gov: Basic guide. Good starting point.
transit-finder.com: Best for solar and lunar; Does Hubble and CSS too. Who saw Chuck's Astronomy live event last week where Chuck attempted to capture the ISS transit the moon? Only to find out later why the capture was not up to his usual standards, because it was the CSS not the ISS. He had a good laugh about it. A good sport. :rofl:
heavens-above.com: Provides a star map and magnitude info.
iss.vierwandfrei.de: Does solar and lunar; Ground track too laid out on a maps.
stellarium-web.org: I use it for the trajectory path.

[astronobob]

Thats one tight fit Dennis, timing and frame.. Awesome

[Averton]

Tops capture Dennis. That is so very close to actually transiting Saturn it's not funny. Great effort!!