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EJN-- I made a rather naive attempt at Campbell's Hydrogen Star with an 8" in a red zone about ten years ago. Needless to say, I didn't catch it.

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??? Cambell's Hydrogen Star is *very* bright, around mag 9, and so is the associated planetary nebula. The trouble is that it's very small, around 7", if I recall correctly, and thus needs good seeing and high power to be resolved from the glare of the star. I saw it last summer with a C8 running at >800x in superb seeing. It was quite easy to see as a round fuzz with a very bright central star. From my latitude of 55N it never gets dark in summer, so I had a NELM of around 4 or brighter when observing it.


Clear skies!
Thomas, Denmark

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It IS a nice tho difficult due to size object in an 8". My toughest planetarty znd most obscure was 5" in diameter and named Vy 1-2. Needs a better night, merely starlike. Apparently a mini mini M57 type thing.


Pete

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Well, you're definitely going to need a very good map. CHS is just a star among thousands at low power. Completely impossible to tell apart from any of the others.

Once you've positively identified the star, run the power up. WAY up. At least 400x and possibly much higher. This thing is tiny. Think "Mars several months from opposition" small. Fortunately, it's quite bright, so it can take the magnification. The only problem is the very bright central star, which will completely mask the nebula, if the seeing is bad. CHS will need just the right conditions to be seen well (mainly very fine seeing), but then it's certainly well visible in an 8". I didn't use a filter and it's not needed at high power, but perhaps the nebula can be identified at low power, using a filter and the blinking technique. I haven't tried it.


Clear skies!
Thomas, Denmark

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Actually, Campbell's Hydrogen star may not be all that difficult to tell from the other stars in the field for a rather "colorful" reason. This is especially true for apertures larger than eight inches, as it often shows its fairly distinctive faint reddish-orange coloration.

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For me, hands down, it would have to be Hannys Voorwerp. And having been the second confirmed visual observer of Hannys made it that much sweeter!

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I'm a few notches down that exclusive list of observers of Hanny's Voorwerp, but I certainly know the scope we're talking about...

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Hi Steve,

You know, up until this past year I've been going down there a couple times a year. And since you've started going down, it's been aggravating to me that I haven't been able to coincide a trip with one of yours. (This past October I had to cancel last minute )

Sooner or later it'll happen!! I truly look forward to sharing some views with you Steve!

It would be an honor!

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For those fortunate few who have access to truly big scopes, they enjoy a particular advantage regarding objects which are tiny and/or of low total brightness. No matter how skilled the observer or perfect the conditions, the smaller scope crowd are left completely out of contention.

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For those fortunate few who have access to truly big scopes, they enjoy a particular advantage regarding objects which are tiny and/or of low total brightness. No matter how skilled the observer or perfect the conditions, the smaller scope crowd are left completely out of contention.

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For those fortunate few who have access to truly big scopes, they enjoy a particular advantage regarding objects which are tiny and/or of low total brightness. No matter how skilled the observer or perfect the conditions, the smaller scope crowd are left completely out of contention.

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Actually, Campbell's Hydrogen star may not be all that difficult to tell from the other stars in the field for a rather "colorful" reason. This is especially true for apertures larger than eight inches, as it often shows its fairly distinctive faint reddish-orange coloration. Indeed, in my 14 inch, the reddish hue is fairly distinctive. It also "blinks" a little with the H-Beta filter, although not to the same extent that other true OIII planetaries blink in the OIII filter. Since my H-Beta also has a booming red secondary passband, the object *really* looks red in that filter as well as in the DGM Optics NPB filter which also has a red passband. Under good seeing conditions, a diffuse disk is often seen that is somewhere around seven to ten arc seconds in size. Clear skies to you.

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Reiner,
I've wondered if the western side of the Erifanus Bubble could be seen. As you note, it's very much fainter than Barnard's Loop in both H-alpha and full color images. Thanks for the encouragement!

Alvin,
You missed the point of my 'complaint.' It's objects such as Hanny's Voorwerp, distant extragalactic globulars, Einstein's cross, etc., which the small scope gang have no hope of bagging. So the most obscure objects are perforce left to those few blessed to peer through optical leviathans.

But there are plenty of objects which are more easily detected in smaller instruments due to large size. In those cases a big scope can be at a disadvantage due to the object spilling well outside the extent of the field of view. A less magnified view that allows some surrounding sky to frame a dim fuzzy can male for easier edge detection.

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Glenn,
I think you mis-read my post. I got your point...but I said "not entirely true". Anyhow I'm not going to quibble about this and small and large scope got its own set of challenges...so no whining here...

When I use my small scope (4 or 6"), I still go out and observe obscure stuff.

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