Another Jupiter Report from 28-29 June

[John]

After reading Stu's excellent report, I've been motivated to post one of my own on my observations of Jupiter last night.

I was using my Takahashi FC-100DL refractor and most of the time I was using a zoom eyepiece plus barlow which gave me 9.55mm - 3.2mm range but the 7-6mm (130x - 150x) setting was giving me the best views.

So far observing the giant planet has been a rather frustrating experience this opposition. The planet has been so low in the sky that the observation window from home has been a period of a couple of hours when the planet appears between my neighbours roof and some large chestnut trees.

 

When I have managed to get a scope onto Jupiter the amount of atmosphere that I've been peering through has caused somewhat poor seeing conditions.

 

Last night the seeing seemed much better and my 100mm refractor at around 140x was showing some reasonable detail on the planet. The Great Red Spot was well positioned on the western side of the disk and over the couple of hours that I observed, moved westwards and eventually out of sight around the limb of the planet. The Galilean moon Io was close to the planets western limb when I started observing and I was able to watch it gradually disappear behind the planet over the next quarter of an hour. Just before the moon vanished it appears to form a "bump" on the limb of Jupiter for a few moments which can look quite odd.

 

The N and S equatorial belts on the planet are well defined with the N one in particular showing scalloped / uneven N and S edges. The equatorial zone showed indicatations of festoon activity and later in the session I notied a couple of clearer festoons eminating from the N equatorial belt and streaning diagonally S across the equatorial zone. The N and S temperate Belts were faintly seen as were the darker polar areas to the N and S of those.

 

The other 3 Galilean moons were nicely positioned as well, enhancing the overall view of this giant of the solar system.

 

So I'm not writing Jupiter (and Saturn a little later in the year) off just because they are low in our skies. Sometimes it's worth making the effort to observe them and to tease out what you can of their detail. My societies observatory S of Bristol has a nice low S horizon so would make observing these targets a little easier than they are from my back yard here in Portishead with it's somewhat cluttered (ot say the least !) horizons.

 

I've attached an image of Jupiter (not my own I ought to say) showing the various surface features that I have mentioned and also a reasonably accurate representation of the view I had last night at around 10:15pm generated by the Cartes du Ciel software.

 

 

 

 

 

 

[Stu]

Great stuff John, alot more sophisticated that mine 🤣🤣. Interesting to be observing the same thing with different scopes from quite different locations and get very similar results.

Last night was a real lesson in patience paying dividends. A quick 5 minute look at the start would have said 'give up, there's nothing to see', but time at the eyepiece, everything cooling off and the planet heading that little bit higher resulted in some good views. Well worth it.

I think I spotted the Northern temperate zone occasionally when seeing allowed but it was fairly fleeting. Shame there was nothing like the detail in and around the GRS which has been there when Jupiter is higher. Bring on 2024 eh?

[jock1958]

Very nice report John. Sadly it clouded over here last night and night before the seeing was average at best! 

[John]

20 minutes ago, Stu said:

...Last night was a real lesson in patience paying dividends. A quick 5 minute look at the start would have said 'give up, there's nothing to see', but time at the eyepiece, everything cooling off and the planet heading that little bit higher resulted in some good views. Well worth it....

 

Spot on Stu