Europa and shadow transit Jupiter this evening.

[John]

Europa has just started it's transit of Jupiter's disk.

With the GRS nearing the central meridian and a small dark barge on the top of the NEB plus decent seeing for a change, it's all looking rather nice

Europa's shadow starts it's transit at around 23:40 hrs I think.

Might not stay clear so I'd better enjoy it while I can !

Edited October 7, 2021 by John

[Kon]

Thanks for the heads up, will get the Dob out

[Kon]

Although it is still cooling down, Jupiter is showing excellent seeing with a lot of details. I spotted the barge in the NEB. I think it is my best Jupiter seeing so far.

[IB20]

I’ve just watched Io appear from Jupiter’s shadow and observed Europa ingress onto the planetary face. Amazingly I could still see Europa in front of Jupiter even after it was entirely on the disc, I can’t quite believe it, that’s the first time I have been able to observe such an event, in a little 80mm too!

The seeing was good at times and I could also see the nice colour in the GRS at 62x and 80x. 

The clouds have rolled in now unfortunately so I think that’s me done.

 

[John]

7 minutes ago, IB20 said:

I’ve just watched Io appear from Jupiter’s shadow and observed Europa ingress onto the planetary face. Amazingly I could still see Europa in front of Jupiter even after it was entirely on the disc, I can’t quite believe it, that’s the first time I have been able to observe such an event, in a little 80mm too!

The seeing was good at times and I could also see the nice colour in the GRS at 62x and 80x. 

The clouds have rolled in now unfortunately so I think that’s me done.

 

Europa stayed visible against the disk for quite a while. It's very hard to spot now though and the sporadic cloud cover is not helping.

I think the moons are visible during the early part of their crossing of the Jovian disk because of the effect limb darkening which allows the moon to stand out better against the limb areas of the planet than it does as it moves more onto the disk.

Whether I get much more observing is in the lap of the cloud gods just now. Some is a lot better than none though

[Stu]

Sounds great! I got back after a long two days at about 8.10pm and Jupiter was shining brightly. Too tired to observe, and now it have clouded over anyway.

Glad you chaps were getting some great views. It’s great seeing the disk of the moons brightly against the limb darkening as John says. To me they always look larger and more obviously a disk when infront of the planet.

@IB20, it’s worth keeping an eye out for a Callisto and I think it’s Ganymede transit, both of which appear darker against the Jovian surface and so are easier to see. They transit less frequently though so are seen much less often that Io or Europa.

[Kon]

Jupiter is 'boiling' at the moment. It is 'funny' because my W seeing is very steady; a smudge of light got my eye and it was M13; it could easily take magnification and individual stars resolved almost to the core.

[John]

The seeing is good here with lots of intricate detail but there is a large back of cloud that keeps swallowing up Jupiter so I'm getting small excerpts rather than a continuous show.

 

[Kon]

The breeze has cleared the clouds and seeing has vastly improved with nice details all along now. I can spot 2 clear barges and possibly a third one. Quite a lot of distinct banding as well.

[John]

1 minute ago, Kon said:

The breeze has cleared the clouds and seeing has vastly improved with nice details all along now. I can spot 2 clear barges and possibly a third one. Quite a lot of distinct banding as well.

Similar here.

I was wondering if any of those pale oval features in the S hemisphere would be showing as the GRS rotates out of sight. Just waiting for Europa's shadow now.

 

[Kon]

4 minutes ago, John said:

I was wondering if any of those pale oval features in the S hemisphere would be showing as the GRS rotates out of sight. Just waiting for Europa's shadow now.

In anticipation as well. I have not seen the ovals before so I will give them a try if conditions stay stable.

[John]

I'm probably going to pack in soon regardless of the conditions. I've got quite a bit of driving to do tomorrow. Hope it stays good for those who stay out  

 

[Kon]

Just saw the shadow coming through, very nice. Waiting for another 45 min for Europa to come through.

[John]

11 minutes ago, Kon said:

Just saw the shadow coming through, very nice. Waiting for another 45 min for Europa to come through.

Yes, I've waited to see that. Quite nice seeing now although Jupiter is now getting lower in altitude. Some "clumpiness" in the S Temperate Belt but nothing that looks specifically "oval-like" with my 100mm scope tonight. I was using the 130mm last time I saw them though.

Hope it keeps good for you

[Kon]

Europa just came through the face of a 'boiling' Jupiter, quite an amazing event in my eyes. Initially as a small protrusion at 9 o'clock (Dob view) and then a few minutes later a nice disk. Conditions deteriorated towards the end. 

29 minutes ago, John said:

Some "clumpiness" in the S Temperate Belt but nothing that looks specifically "oval-like" with my 100mm scope tonight.

I also saw some grey looking 'smudges' with some finer features  but nothing to call oval-like. 

 

Thanks again for the heads up, it was a nice event.