Posts Made By: William Travis

Star Party organized by Longmont Astronomical Society at North Sterling State Park, 12 miles N of Sterling, CO. Fri and Sat nights, Apr. 16 and 17th. Chimney View CG will be astronomers-only. Nice large sites, on large reservoir. Camping fee waived, but $5/day park pass req. Very dark skies. New 30 inch Astro-Systems dob should make an appearance. This is a local event, in what passes for spring on the western High Plains, so really bad weather can nix it.
More info:
[email protected]
state park web:
http://parks.state.co.us/default.asp?parkID=61&action=park

Like many I end up buying sight-unseen, and websites are not always informative Can someone briefly brief me on how some EPs like some Nagler's and Meade UWA have both 2 inch and 1 1/4 inch barrels? I assume the 1 and 1/4 inch insert comes out, so you get the full opening of the 2 when using a 2 inch focuser or diagnoal? Any reason to avoid such EPs when you'll be using it on 2 inch equipment exclusively?

Thanks!Bill Travis

Donald:

Doesn't hit the mark?????? My goodness, that's a wonderful image. Maybe us visual-types (at least this humble visual observer) are more easily impressed than those folks over on the astro-photo forum. Don't listen to them.

Bill Travis

Structure in Galaxies

I’ve been working on a list on this very issue since the fall. I put it together as a “To See” list with ideas from various sources as to potential visible structure in galaxies (SAC's great M and NGC downloads; ideas from members of the Cloudy Nights and Astromart Deep Sky chat groups, etc.).

Obviously, as pointed out in this thread, ability to see structure depends on seeing and equipment, so I’ve been using a simple observing rating system to reflect differing access to sites and scopes:

I: mid-size scope (8-11) in good suburban conditions (most little dipper stars, milky way at least barely vis)
II: big aperture (12.5 plus) in good suburb skies (I believe aperture helps in mod light pollution)
III: mid-size in dark skies
IV: big aperture in dark skies

Though it was also pointed out here that “dark skies” are not always sufficient, there’s seeing and transparency. And this system is redundant (any structure seen at condition I, would be at seen at I+, but I am keeping a log and sometimes observe the galaxy first through a friend’s big scope at dark skies then try it at home in my 9.25. (I like to press the backyard limits of the hobby.) In the list below observing status (I-IV) is assigned only where I’ve actually observed the galaxy. Most of my III’s are a single night at Devils Garden Campground in Arches national park, UT, a remarkably dark place.

Messier:
M31: dark lane at II, 2 lanes at IV
M33: spiral at IV
M51: spiral at I, II and III; bridge to companion and structure within arms at IV
M64: blackeye maybe at III, definite at IV
M74: spiral
M82: dark band/constriction at I, irregularities at II and III
M83: spiral
M95: spiral
M96: spiral
M99: arm at IV
M100: spiral
M101: spiral
M104: dust lane, asymmetry at II, III and IV
M108: mottling

NGC:
253: various structure
772: arms, tail
891: dust lane at III and IV
1365: spiral
2403: spiral
2903: Leo: a nice surprise: Bar visible, with bright halo at III.
2911: dust lane at IV
3079 UMa: Edge on with asymmetric wings, and mottled texture (III).
3184 UMa: Large oblique edge-on with a dark lane in and out of visibility (III).
3227: pair at III and IV
3556: edge one, dust lane
3628: dust lane, asymmetry
4038/39 Cor (Interacting “Antenae” galaxies): Too bad on this neat object: Just too faint for antenna structure, only a hint of two lobes (at III, but lower in sky).
4274 CVn: No spiral structure visible; nucleus and elongate halo (III).
4449 CVn: complex structure, seems like two nuclei; noticeable curled-up east end (III and IV)
4559: spiral arms
4565 Coma: this was a downer: even in the best dark skies the 9.25 cannot seem to resolve the dark band in this famous edge-on very well, averted imagination helped, but dust lane not consistent at III. Easy dark lane at IV.
4567: linked pair
4535 Vir: large, textured object but no further structure visible (III)
4567/68 Vir: two lobes of linked pair visible, with nuclei in each (III)
4631: dark lane
4656: hockey stick visible at III and IV
4725: bar
4752: dark lane
4754/62 Vir: 54 shows large nucleus, but that’s it; 62 is striking edge on, no dust lane visible, but obvious central bulge (III)
5128: dark lane
5746 Vir: nice edge on, dust band not visible (III)
6207 Her: bright nucleus, not other vis structure (III)
4490/85 CVn: S shaped spiral visible (2 extended arms); w/ small companion (no link) at III.
6207: mottled with bright nucleus
7331: spiral structure and dark banding
7479: spiral

Other Interesting Galaxies to see:

Other edge-on's like NGC 55, 253; 891, 2683, 3115

Odd shaped galaxies like 2549 ("Bear Claw"), 275, 1097, 4490, and other Arp galaxies

Galaxy clusters/groups such as Abell 779/NGC 2832, Hickson 44/NGC 3185, "The Box"/NGC 4169; the face in Markarian’s Chain (great at III).

Any additions or amendations appreciated!


Bill Travis

Vincent:

Can you offer any comments on the 20" Nightsky (perhaps you have done so elsewhere?).

Bill Travis

Vincent:

Thanks for starting this thread and the descriptions and photos.

I'd like to see more pics and hear about other observers' dark sky sites.
The ones often used here on the Colorado Front Range are shown at:
http://ncastro.org/spsites.html

Campgrounds are a mixed blessing, but I've had good luck at Devils Garden in Utah's Arches National Park (sites on the east side of the road), and Pebble Creek in Yellowstone National Park (with friendly, supportive rangers, but the occasional grizzly bear--I hang my bear spray on the tripod spreader). Drawbacks are smoke and ash from nieghbor campfires and need for quiet late at night. Someone should start a list of good observing campgrounds.
Bill Travis

Inge:

If I recall, Inge, at summer's start you were saying goodbye to darkness and musing about taking the scope to the Canaries or somewhere. I think about you (and fellow amateurs at high latitudes) as the nights grow longer and am glad to see this post! Even here, at 40 degrees (I live a few miles north of Baseline Road, named after that parallel) we're planning southern excursions to see more.
Cheers,
Bill Travis

Inge:

I recall your post at this time last year, saying goodbye to dark skies, and can't help but see this as a bit poignant. I enjoy reading your reports--thanks for them and the ones to come.
Cheers,
Bill Travis