Time travelling Saturn?

[badhex]

Hello all, 

Very happy to report I've finally had my first proper observing session this year! Observing report to come - however until then, I have made a properly head-scratching observation and need some help figuring it out. 

Observing from the Italy in the bay of Naples last night (Bortle 5) I managed to catch Saturn as it plummets away from us with my ZS73 and APM Superzoom at 7.7mm / 56x. I was using stellarium to figure out the configuration of moons; Titan was easy, and also I caught Iapetus since it is so far out, but the remain points of light were very confusing.

Stellarium says that this was the configuration at the approx time:

However, what I saw and initially wrote in my notes ("looks like Sagitta with Saturn in the middle") before checking stellarium was more like this (slightly edited to remove moons etc I could not see):

The problem is that this is what Saturn looked like at about 2030 - not 0100, 4.5hours later. 

I checked for settings/location issues, and I checked with different EPs but I was definitely seeing a Sagitta shaped configuration of light points like the above. I have zero doubt about that. What's going on here?

There is another star on the first image ie the correct time, below Rhea, but that star is mag ~20 and I cannot believe that this is what I was seeing. Circled below for reference:

[globular]

HD 211990 was about in that position and it’s magnitude is about 9.1 - not that dissimilar to Rhea’s 9.9.

[badhex]

21 minutes ago, globular said:

HD 211990 was about in that position and it’s magnitude is about 9.1 - not that dissimilar to Rhea’s 9.9.

Ah yes, sorry I wasn't very clear; HD 211990 was in this position at about 2030 CEST according to Stellarium (the lower yellow object) 

However, I was observing Saturn at 0100 by which time it had moved to the position in this image:

However this does not match what I observed at 0100. I observed something akin to the first image, with a shape like Sagitta. Very confusing! 

Edited September 7, 2023 by badhex

[globular]

This is what skysafari gives for 1.00 last night in Naples. The star below Rhea is HD 211990…..

 

And at 22.30 it gives…

 

Not sure why stallarium is showing it differently… maybe one of us has the date or location wrong. 

 

[badhex]

Thanks for the screenshot Glob, your Skysafari at 0100 shows what I was seeing. The two objects looked roughly similar mag with one being a slightly different colour to the other. I forgot I had Skysafari as I've always used Stellarium, so I just checked - lo and behold, my skysafari also shows the correct configuration of objects:

 

So it's definitely an issue with Stellarium. I've checked all the settings again and they are definitely correct as far as I can see, but the objects are not in the right places. I'm not sure what is happening here, but maybe I'll clear the app cache etc and see if there's a some temporary bug. 

 

Edited September 8, 2023 by badhex

[badhex]

Well, clearing app cache made no difference so next step would be a reinstall, but not doing that whst on data only since it's half a gb. 

This is very odd; I can't understand what could have gone wrong here, but it surely must be time/date/location related. 

[globular]

I can't help you with Stellarium (don't use it) - but at least you now know you've not time travelled and it just a Stellarium issue somewhere.

p.s. hope you're enjoying Naples.  Ice-cream to die for......

Edited September 8, 2023 by globular
typo

[badhex]

42 minutes ago, globular said:

I can't help you with Stellarium (don't use it) - but at least you now know you've not time travelled and it just a Stellarium issue somewhere.

p.s. hope you're enjoying Naples.  Ice-cream to die for......

Cheers! I'll put the DeLorean back in the garage.

Yes, love Naples, we go every year and spend at least a few days there. Actually we spend most of the time on Ischia, and last year also Ponza, though not Capri - not for me!

[Bugdozer]

Is it possible that light takes 4.5 hours to travel from Saturn to Earth and Stellarium was showing you the positions of moons as they physically were at that time rather than as they would appear? Seems unlikely but it would explain it. 

[badhex]

It's a good shout and but as at today, light from saturn only takes approx 1h15m, and would have been a bit less a month ago. I suspect a temporary issue with Stellarium, which I think is now resolved.