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[Paulie pchris00]

It's almost time for bed, so the full report will have to wait, but Bill, Doug and I made the best of less than ideal conditions last night. Given the forecast of yesterday morning, though, I can't complain. We took a chance heading out to the observatory, but it mostly paid off.

Quick run down of some of what we saw.

-The outer solar system. All five major outer planets, and Garradd.
-The Ring
-Double Double
-M17 & M16, the Swan and Eagle.
-M11 Wild Duck
-Gamma Delphinus (nice Albireo-like double
-Luna
-M42

Thanks to Bill for coming out, and bringing our visiting astrophysicist Doug. I really enjoyed this session, especially pushing Jupiter and the Moon, catching different features and pointing them out to each other.

Attachments:

[dapple]

Much thanks to Paulie and Bill for making this happen! I haven't had an all night observing session like that in almost a year. The site was great, and it was definitely fun swapping views. I was particularly impressed by Paulie's star hopping ability. That big scope in the picture? Yeah -- NOT a go-to. But it sure can pump out those good views. And of course, thanks to Bill for picking me up and helping me avoid the hell of dropping off a rental car at O'Hare at 5am and riding public transit back to U of Chicago.

The evening started out clear, with the Naked Eye Limiting Mag (NELM) ~ 5.1. But by 11, I think the NELM had dropped to at most 4.5, and 4 by midnight as we started getting waves of clouds coming overhead. But some pretty big holes opened up that we tried to take advantage of.

The evening had quite a few firsts for me:
- First time eating at McD's (in 10 years) [yes, I know I'm an arugula eating yuppie from communist California]
- First time actually looking at the moon in detail
- First view of Jupiter (well, I may have done that before, but the view must've been overwhelming unimpressive, especially compared to last night, that I nearly forgot). I should say that Jupiter looked amazing through the 6" and the 16".
- First view of Neptune & Uranus

We played around with some colored filters on Uranus. [Is there any way around saying that?] Since it only looked grey to us, I thought we could tell the color by seeing how it responded to different filters. Green, still there; Orange, increased contrast with the background but fainter; Red, completely gone. I think a comparative study against Neptune and Jupiter is in order.

On Jupiter, we also caught a Great Red Spot transit (first), and Io exiting it's transit of Jupiter (first). Bill called Io a pimple on Jupiter's face. I think Io's feelings were hurt!

In addition to Paulie's list above, I hit up a few more in the 6", mostly doubles because of the moisture in the air:
- M26 : OC in Scutum
- alpha Capricornus (Algedi) : a line of 4 stars, with a possible double double on the inner two
- 15 Aql: double star
- eta Pegasus (Enif) : a yellow and blue double star
And then Bill guided me to the Double Cluster and the ET cluster with his laser pointer.

Paulie and I tried to find a small planetary nebula that Garrod will pass by soon, IC4997. We think Paulie found the field, but there was no way of knowing which star was actually the planetary.

Okay, now that I've buried the lead enough, what is up with my shirt in that photo!? Am I ET or Iron Man, or something?

Thanks again, guys!

[patrickm]

Fun. Jealous. Bummed. Happy. Cool.

[Paulie pchris00]

I haven't even begun to write anything yet, but the pictures are on Photobucket.

s263.photobucket.com/albums/ii157/pchris00/2011-8-19-20/

I will put them in a proper post as soon as I can.

[Paulie pchris00]

Aug 20, 2011 11:59:40 GMT -6 dapple said:

We played around with some colored filters on Uranus. [Is there any way around saying that?] Since it only looked grey to us, I thought we could tell the color by seeing how it responded to different filters. Green, still there; Orange, increased contrast with the background but fainter; Red, completely gone. I think a comparative study against Neptune and Jupiter is in order.

Okay, now that I've buried the lead enough, what is up with my shirt in that photo!? Am I ET or Iron Man, or something?

The orange filter showed Uranus surprisingly bright. The methane in it's atmosphere strongly absorbs orange/red, right? As for a comparative study against Jupiter and Neptune, I can try that, and if possible get some images to post. I've already done extensive filtering of Jupiter, and have plenty of images that I'm eventually going to get around to posting. (I generate more data than I can efficiently process, which is one of the reasons I've cut back on my blog writing. I can barely get stuff posted here in a timely manner, let alone worry about my blog.)

I'm also very curious about the "star" we saw below Uranus. Given the system's axis tilt, the position seems plausible that it could have been a Moon. I'm going to keep a watch for it from now on.

Lastly Doug, was there something reflective on your shirt? That spot is just as bright as the reflector on the telescope pier!

[dapple]

Hehe, yes, the logo on the shirt is reflective. I didn't realize it was that reflective!

I can't seem to find methane's optical absorption spectrum. Most things concentrate on the near infrared absorption. I suspect the effect has more to do with light pollution than anything intrinsic in Uranus. That orange filter is probably centered around 600nm, which is one of the wavelengths skyglow filters block at. I'd guess that the sky background just got chopped more than Uranus.

I'm interested to hear if that turns out to be a star or a moon. Checking Carte due Ciel, there was a mag 11.68 star in about the right spot that night (assuming our eyepiece view had north up?). Catalog name is TYC 2-273-1.

[Paulie pchris00]

Aug 21, 2011 11:56:06 GMT -6 dapple said:

I'm interested to hear if that turns out to be a star or a moon. Checking Carte due Ciel, there was a mag 11.68 star in about the right spot that night (assuming our eyepiece view had north up?). Catalog name is TYC 2-273-1.

I do believe north was up, but the star was south.

[dapple]

OK, that matches. I recall it was to the lower left of Uranus, which also matches this star. The only other question is how far? I suspect we had a fair amount of magnification.

Just for kicks, I was thinking about how I'd do that comparative study with only visual observing. I think I'd use a low enough magnification so that Uranus looks star-like so that the observations would reflect the total brightness. Also, hopefully some comparison stars would be in the field of view with a low enough magnification. Baring comparison stars, I'd probably want to figure out how the background changes with each filter by looking at an open cluster with the same mag and general area of the sky and checking for the limiting magnitude. Perhaps overkill.

[Paulie pchris00]

I don't think that's overkill. It's thinking like a scientist, trying to get a set of control observations. However, it's far beyond my capability. I would probably have to use my battered old point and shoot Vivitar, which sometimes has trouble picking up the Galilean Moons. The outer planets would give that camera trouble without filtering. Reducing the photons by filtering might kill my chances at getting anything.

[Chicago Astronomer - Astro Joe]

I have always said that Neptune looks Blue-Green, while Uranus looks more Green-Blue.

I think the atmospheric conditions skewed lighting somewhat that night of yours.

[patrickm]

When under (suddenly rare) clear skies, Neptune always looks blue blue to me. It is my third fave planet... Uranus usually appears to have a very faint, greenish blue pastel tint. Not nearly as bold.

Eager to hang out with under clear, dark skies and compare. Using a few white, control stars seems like a cool idea, especially if we can side by side them with the planets. More scopes!!