RobertI

Very nice sketch. 

That really does look the business. A very ‘together’ setup. 👍 Funnily enough I was thinking today that I should get my 102ED on the CG5 so that I have free hands to sketch Jupiter. The CG5 isn’t white though, won’t look so good. 😉

Lovely looking scope. As you say the objective looks perfect. Why is there a hole in the back of the diagonal do you think? 

Will definitely put that one in the diary. 

13 hours ago, Greymouser said:

Can someone please persuade me

It’s actually part of UK law. You must buy one. 

I’d have a look at the Sky Guide app. I did a review of it about three years ago here. Things have moved on somewhat since then, and they have new features, and an extended database of high definition images which you pay extra for. The big downside is the ‘full fat’ costs £35 PER YEAR! If there is a way to trial it without committing, might be worth a look. I did end up buying the full version when it was much cheaper - I used it quite a lot alongside Sky Safari, but ultimately I guess I couldn’t justify the annual cost, and discontinued. 

Yes probably Winter for me in terms of skies and targets, although this time of year is brilliant from a practical perspective - still warm and getting fully dark reasonably early makes observing a joy.  

Make sure you keep us posted with progress. 👍

7 hours ago, NGC 1502 said:

At 23.29 Io appeared as a “pimple” attached to Jupiter’s limb😊. By 23.34 the bright dot of Io was fully on Jupiter’s disc.

As the minutes ticked by Io became progressively harder to see as it moved further from the limb darkening. By 23.50 I could no longer discern Io, but the shadow remained easy to see.

Pretty much exactly what I saw! 

4 hours ago, Louis D said:

Just saying, when I take a statistical cross section of an observing field of dozens of scopes of all types, and the SCTs are putting up the least pleasing images regardless of aperture, I'm going to blame the design.  After attending multiple public star parties in the 90s, it was clear enough to me that I took a hard pass on buying an SCT and instead bought a Dob (Newtonian).  A Dob simply wasn't what I thought of as a desirable telescope as a newbie (big, dumpy, awkward, undriven, yard cannon, etc.), but multiple comparisons over several years lead me to that decision.  I'm still using that scope 24 years later on a regular basis.  I've since added an achromat, an ED, an APO, a big Dob, and a Mak, but I still love that midsized Dob all these years later.  Other than an EdgeHD, I haven't seriously considered getting an SCT of any size in those 20+ years.

I have to say, if I knew back in 1999 what I know now, I wouldn’t have bought an SCT. As I mentioned in a separate thread, it was the scope I had always wanted as a kid back in the early 80’s (as did many people) and when I resurrected my hobby I bought my ‘dream’ scope without really doing any research. Having said that, nearly 25 years later, it has stayed with me through numerous house moves, accompanied me on numerous holidays, given me some truly memorable views and now sits alongside my new 102ED when I want to do ‘dual’ observing. I guess we make the best of what we have!

6 minutes ago, Stu said:

Excellent report @RobertI, glad you managed to see that. I wasn’t out last night, but do want to start catching some of these events.

I’ve always found Io and Europa to appear as bright disks when they first appear against the limb darkening, but they then become increasingly hard to see until they disappear, only reappearing near the other limb.

Cheers Stu, I’ve only observed a couple shadow transits and being able to the see the moon’s bright disc on the planet was something new. Interesting to hear that what I saw is common for Europa and Io.

11 minutes ago, Stu said:

Shadow transits to me have always been possible to see right the way across, but you did say the seeing was poor so perhaps that’s why you lost it?

I think my description was confusing (I’ve now removed the offending sentence), I did manage to see the shadow across the whole disc!

13 minutes ago, Stu said:

The ones to look out for are the rarer transits of Callisto and Ganymede. They orbit further out and more slowly, so they transit less frequently. The number of observable transits is actually pretty small, but well worth looking out for. That’s because they have a lower albedo than the other two and appear dark against Jupiter’s bright disk. You can track them right across. I once recall viewing a double shadow and then seeing what I thought was a third shadow. This turned out to be Callisto. On careful observation you could tell the difference as it wasn’t quite as inky black as the shadows and was softer around the edges, while the shadows are razor sharp.

The other effect to watch for as opposition approaches is that the shadows get closer to the moons, and at opposition actually the moons are overlapping the shadows. Makes sense as the Sun is behind us, with Jupiter opposite it in the sky so everything lines up nearly perfectly.

Fascinating, I have a lot to look forward to with these transits over the coming months. I need keep a close eye on what’s happening. 👍

15 minutes ago, Stu said:

Sorry for rambling on!! 😜

Ditto. 😆

Just seen an amazing shadow transit of Io - full(er) report here: 

The clouds cleared and consulting Sky Safari, I saw that a shadow transit of Io was just starting. Five minutes later I had the 102ED with binoviewers set up at around 170x. The seeing was awful with Jupiter ‘boiling’ but the shadow of Io was perfectly clear, a tiny black disc which seemed totally unmoving as the other moons danced around. Io itself was really close to the limb of Jupiter and over the next few minutes I watched it touch the limb and then start to move across the face of the planet. What amazed me most was that, because it was moving along one of the dark equatorial belts, it was visible as a tiny bright disc, and was visible for a good ten minutes until it finally disappeared against the disc of Jupiter. Quite an experience. 🙂 Anyone else see it?

20 minutes ago, Cosmic Geoff said:

Sounds like my CPC800 before I tweaked the collimation.  My C8 SE did not produce 'hairy' stars.  

Interesting, I’ll do some proper tweaking and testing to see what I can do, it would be great to find out I can get pinpoint stars with the scope, although I think mirror flop may end up spoiling the party. 

I’m not an expert on doubles by any means, but have observed a few tricky doubles of this type, with the secondary on the diffraction ring. In general I have found that really high mags will eventually reveal the secondary clearly in the diffraction ring if the conditions are right, but these higher mags are trickier to reach in my small scopes, or become too dim. I guess my results have fallen into one of the following main categories, which are  still pretty subjective and probably not very useful to anyone! 😆

1. Not seen
2. Suspected brightening - glimpses of slight brightening of the diffraction ring in the correct position position angle 
3. Definite brightening  - obvious brightening at the correct position angle
4. Resolved - the secondary clearly stands out as a star in the diffraction ring 

To address the original question, I guess in this situation where the secondary is on the diffraction ring, and there is a clear gap, the term “split” isn’t really useful anymore and the above descriptions might be more useful? 

Interesting post, I’ll take your word for the logic of your analysis! I think ‘mushiness’ is too vague a term to really understand what problems people are seeing. It seems like there are many problems. My personal experience with my C8 is that bright stars are not always pinpoint and can seem a bit ‘hairy’ (I think @michael.h.f.wilkinson coined this term - I like it!). This makes certain doubles with bright primaries difficult to split and it means I tend to avoid using the scope for double splitting, probably unreasonably so. I think part of the problem is that SCTs have such long focal lengths you can often forget how high a power you are observing. I’ve also found that low contrast planetary features are not as distinct as you would hope from the aperture. But I’ve never really noticed any kind of ‘mush’ types issues on the moon or clusters. Galaxies and nebulae are mushy anyway! 🙂

Superb observing report and great read. Your carefully selected images really bring to life the experience of observing with a large scope. M13 is amazing through an 8" so it must be stunning in an 18". This is an interesting contrast to my recent observation of M13 using my 4" frac, where I could resolve a reasonable number of stars at x200, but the view was very dim and not really possible to go any higher - not really the right size scope for viewing these wonderful globs! 

BTW it would be useful if you added the scope details at the start of the report (I know it's on your website version). Keep them coming.  

36 minutes ago, Marvin Jenkins said:

how do you like that mini giro?

The Heritage 130P, being so light, works really well on the mini giro. It’s a lot of light gathering for such ultra-potable setup. I wouldn’t use the mini-giro for anything bigger though, although plenty of folk have. 

37 minutes ago, Marvin Jenkins said:

I changed the focuser for the unit used on a 130 pds

Yes, I tried to track down a cheap 130P OTA myself so I could ‘pimp’ it in the same way, but I never managed to find one.

39 minutes ago, Marvin Jenkins said:

I could have just bought a 130 pds I hear you all cry and you are all 100% right.

True, but the 130PDS has a bigger secondary for imaging, so you probably got better views with your 130P! 

Agreed, I have had a lot of success with my Heritage 130P, usually mounted on my Mini Giro WR. It’s good for deep sky (memorable views of the Veil from a dark site), excellent doubles splitter and useful on the moon. Never really tried it with the planets but I’m confident it would acquit itself well. In fact I like the 5” Newt format so much I have considered a 130PDS - shame they don’t do a 130P specifically for visual. 

Looks like it’s designed to slice through atmosphere like a hypodermic syringe (I think that’s a mixed metaphor!) 🙂

When I was a teenager into astronomy in the early 80’s, I had a Fullerscopes 6” Newtonian. But what I really wanted was a Celestron SCT. Back then the Celestron brand was considered upmarket and SCTs were aspirational scopes - at least that’s how I remember I perceived things as a teenager. So naturally when I resurrected my interest in the late 90’s I bought the scope I had always wanted - a Celestron C8 (marketed as the G8 with the non-goto CG5 mount). It has been a really good all round scope over the years, well used and twenty odd years later it is still in good condition as it’s built like a tank and has an enclosed mirror. Other scopes in my arsenal, particularly the 102ED have shown me it’s optical shortcomings in certain areas, especially doubles, but for globulars and faint fuzzies it’s still the best scope in my arsenal, and it’s no slouch on planets and luna on nights of good seeing. Mirror shift is awful and mirror flop means the collimation varies slightly as you move it around the sky but I’d never say it moves out of collimation enough to make an observable difference. But it is very portable and easy to set up. Overall a very easy scope to live with. 

7 hours ago, Sunshine said:

It caught me a little by surprise looking at my SGL account info, realizing that it’s been five and a half years that I have had the amazing pleasure of being a tiny part of SGL. Oh my gosh I can’t believe it’s been that long, you all have had patience with me. 😂
 

Everyone here has been incredible, so friendly and patient, you folks are salt of the earth kind of people who just want to enjoy the night sky and each other’s company, even if it is just within this digital space, as many of us are separated by hundreds or thousands of kilometers.  Thank you all for your likes, laughs, confusion and even sadnes, I look forward to another five telescopes….ahem, years!

I always enjoy reading your posts, so thank YOU!

Amazing! We astronomers live for those special moments don’t we? Sounds like Zeta Hercules was the perfect test for the 4” - truly memorable by the sound of it. 🙂 Checking back on my observing log, I have also struggled to see this with my 4” refractor with nothing more than a suspected brightening of the diffraction ring. With my 150 Newt I had more success, getting a clear view of the secondary, but it took excellent seeing and a magnification of 540x to achieve it! I will persevere with the refractor….

That’s the best one yet! 😂😂 Although to be fair the finder is pointing in the right direction even if the rest of the scope is not! I think this “top of the line” scope (see description) is wasted on them. 

2 hours ago, KimG said:

OK , so I have been an astronomer for more than 20 years, seen several comets, all the Messier catalogue bar 1,  A decent number of NGC objects, the space staion lots of times even this morning, starlink chains, iridium flares and meteor showers etc. 

So, at about 5:08 this morning moving at a brisk speed across the southern sky at around 15 or 20 degrees above the horizon was the strangest sight I have ever seen, to the naked eye is was a bight moving cloud about the size of the moon, in my bins there was a very bright sattelite behind the cloud which had lit the cloud with a flare like shape of light, just above the moving cloud was a short chain of lights very close together and equal brightness, several magnitudes fainter than the main bright object (which was brighter than Rigel by a couple of magnitudes) there were other fainter lights slightly above and ahead of the chain. The entire ensemble, cloud and all was moving briskly from west to east and had passed across the sky in less than a couple of minutes. Now if these had been just points of light it would have been striking enough, but to see a huge cloud (as I said, roughly but really a good bit bigger than moon size) moving as well has left me puzzled to the absolute max. I didn't have any meanse of recording it unfortunately, as my description beggars belief I do anticipate a fair amount of sceptisism, but I am not seeking any kind of notoriety or fame, merely reporting what I observed. Later today I will do a sketch based  and post it up, trully, for anyone who knows the night sky well, this was the strangest thing you could 

….. and then you woke up. 😁

Seriously, certainly sounds like you witnessed the Starlink deployment and you describe it perfectly. 

It’s lucky we have such a wealth of knowledge here on SGL, this would be fodder for a panic over an alien invasion anywhere else!