Europa emerging from shadow - 7th September 2021

[Stu]

I noticed that tonight at around 9.40pm Europa is due to emerge from Jupiter’s shadow a little way from the limb. Should be interesting to watch, presumably it takes a moment or two as it is a disk, rather than blinking into sight instantly like a star.

Skysafari says 9:40:17 but I don’t know how accurate that is, and the time will vary according to your location so do check first.

EDIT

Actually, I zoomed in and it shows the whole event taking much longer than I expected. Full eclipse ends at 9:38:53, but the final penumbra doesn’t clear the limb until 9:44:21. I guess it will show as a gradual brightening, it is far too small to see the progression.

[Pete Presland]

Thanks for the heads up, looking like another glorious night tonight.

[Deadlake]

There is also a GRS transit tomorrow at 22.47:05  (8 Sep), shame about the weather other wise ideal viewing height. 

[Pete Presland]

Wow, that was spot on for timing!

[Stu]

6 minutes ago, Pete Presland said:

Wow, that was spot on for timing!

When did you spot it Pete? Seeing was quite wobbly here but I first picked it up at 9:40.45, when it was just on half covered in the umbral shadow. That was with my 4”. Was quite cool, a slow fade up.

[Deadlake]

43 minutes ago, Stu said:

When did you spot it Pete? Seeing was quite wobbly here but I first picked it up at 9:40.45, when it was just on half covered in the umbral shadow. That was with my 4”. Was quite cool, a slow fade up.

Wobbly with my 5” too. However acclimating quicker tonight. Seeing better, however 4 mm TOE gives best views so far, need to move country or maybe just county to get a better view.

Edited September 7, 2021 by Deadlake

[wulfrun]

I had the Heritage 150P earlier and was watching, with a 5mm BST in. I clocked Europa appearing around 9.40/9.41. Quite eerie to see it pop into existence from nothingness! Maybe 5 mins later it was "normal service".

Edited September 7, 2021 by wulfrun
typo

[Stu]

24 minutes ago, wulfrun said:

I had the Heritage 150P earlier and was watching, with a 5mm BST in. I clocked Europa appearing around 9.40/9.41. Quite eerie to see it pop into existence from nothingness! Maybe 5 mins later it was "normal service".

Nice one. Looks like we saw it at about the same time. First one I’ve seen I think.

[Stu]

1 hour ago, Deadlake said:

Wobbly with my 5” too. However acclimating quicker tonight. Seeing better, however 4 mm TOE gives best views so far, need to move country or maybe just county to get a better view.

Did you see it emerge from eclipse?

[Deadlake]

Only just…. Mirror diagonal shows more of Jupiters belts than prism.

Edited September 8, 2021 by Deadlake

[Pete Presland]

I was going to image it with the C9.25, but i thought it would be nice just to watch for once. I could see it around 9.40.30, quite faint but quickly brighteneing, by 9.50 twinkling quite brightly. Thanks for the heads up.

[Stu]

1 hour ago, Pete Presland said:

I was going to image it with the C9.25, but i thought it would be nice just to watch for once. I could see it around 9.40.30, quite faint but quickly brighteneing, by 9.50 twinkling quite brightly. Thanks for the heads up.

Good stuff, quite fun wasn’t it?

Looks like you picked it up about 15 seconds before me, the benefit of larger aperture I guess 👍

I checked for variations in timing by location but it looks like it is way to far away for any parallax effects to make any difference.

[paulastro]

20 hours ago, Stu said:

I noticed that tonight at around 9.40pm Europa is due to emerge from Jupiter’s shadow a little way from the limb. Should be interesting to watch, presumably it takes a moment or two as it is a disk, rather than blinking into sight instantly like a star.

Skysafari says 9:40:17 but I don’t know how accurate that is, and the time will vary according to your location so do check first.

EDIT

Actually, I zoomed in and it shows the whole event taking much longer than I expected. Full eclipse ends at 9:38:53, but the final penumbra doesn’t clear the limb until 9:44:21. I guess it will show as a gradual brightening, it is far too small to see the progression.

Stu, I was giving my TS 6 inch f6 Newt ota first light last night and just happened to catch this event. It did indeed take a few minutes to come to full brightness.  I saw it when it first appeared, quite a surprise when you're not expecting it.  I didn't time how long it took, but did look at my watch after it had been brightening a while and it was 9.40.

I'll be posting my findings re the ota in due course.  If anyone can't wait to know, this is a clue.....👍.  😁

[Pete Presland]

7 hours ago, Stu said:

Good stuff, quite fun wasn’t it?

Looks like you picked it up about 15 seconds before me, the benefit of larger aperture I guess 👍

I checked for variations in timing by location but it looks like it is way to far away for any parallax effects to make any difference.

Its was great fun, i message and friend who is not particularly a keen astronomer. But he has a small scope and has been watching the Moons recently a fair bit, he was amazed that you could percieve the motion in real time,  not heard back yet.

[Stu]

2 hours ago, paulastro said:

Stu, I was giving my TS 6 inch f6 Newt ota first light last night and just happened to catch this event. It did indeed take a few minutes to come to full brightness.  I saw it when it first appeared, quite a surprise when you're not expecting it.  I didn't time how long it took, but did look at my watch after it had been brightening a while and it was 9.40.

I'll be posting my findings re the ota in due course.  If anyone can't wait to know, this is a clue.....👍.  😁

Good stuff Paul, sounds like you picked it up pretty quickly then! 👍👍