Jupiter, GRS, Europa and shadow transit.

[chiltonstar]

Monday evening 3rd August at about 23:30, at an altitude of about 16 degrees (from Oxford).

At the moment, the weather is uncertain so we may be lucky and have a clear patch or two.

Chris

[Stu]

Nice one, thanks Chris. 23.30 looks like it should be excellent if clear. Europa should be potentially visible against the limb darkening. Must finish off my 8” f8 for these planets plus Mars of course!

[chiltonstar]

3 hours ago, Stu said:

Nice one, thanks Chris. 23.30 looks like it should be excellent if clear. Europa should be potentially visible against the limb darkening. Must finish off my 8” f8 for these planets plus Mars of course!

Yes,  defo one for the 8 inch f8. It would be interesting to see how @John's baby makling performs on it, and maybe the classical cassegrain? 

Chris

[Stu]

21 minutes ago, chiltonstar said:

Yes,  defo one for the 8 inch f8. It would be interesting to see how @John's baby makling performs on it, and maybe the classical cassegrain? 

Chris

Won’t be ready for them unfortunately Chris. I have just ordered some flocking for it, thought I might as well while I had it all apart. Might blacken the edge of the secondary too, what’s best to use for that? Will post up elsewhere.

[John]

I'm following these events under rather misty conditions here with two 90mm scopes - the mak-cassegrain and a F/11 achromat refractor (Celestron branded like the mak-cassegrain).

Seeing is stable but detail hampered by mist and thin cloud.

I could not see Europa itself but it's shadow is clear against the north equatorial belt. Great Red Spot has come on to the planets disk now. I'm getting 4 belts plus the darker polar areas. Suggestions of a couple of festoons from the NEB diagonally southwards.

The views are very similar between these scopes as might be expected. There is a touch of false colour around the planet with the refractor and this contrasts with the totally CA free image from the mak-cassegrain. I feel that lack of CA gives the mak the edge on contrast and sharpness tonight.

I'm about to loose Jupiter behind a tree but it's been nice seeing some of this unfold.

Thanks for the heads up Chris

 

 

[chiltonstar]

I've just had a good session too. Jupiter was just visible through thin cloud, the shadow was clear but intermittent and then miraculously, the cloud cleared leaving a haze and the seeing improved. The shadow was sharp and stable and in the position indicated in SkySafari; Europa itself suddenly came into view as a lighter disk slightly higher on the belt than in SS I believe, and the GRS slightly earlier than the SS position. A glorious sight!

Chris

[Littleguy80]

Many thanks for the heads up on this Chris. I respotted my dob with the Catseye triangle centre spot and cleaned the primary mirror yesterday. A couple of trips in to get the mirror clips adjusted to removed astigmatism from pinched optics. The work was rewards with some lovely views of the shadow and Europa appearing at the limb. The GRS looked stunning in the moments of good seeing. Saturn was looking particularly good. Put my mind at rest with regards to the dob working as it should following it’s maintenance. Some of the best views of the planets I’ve had this year.