M51 Redux

M51 -- Whirlpool galaxy
Whirlpool and friends

Almost at the left edge is NGC5198, an eliptical galaxy about 170 million light years away; the extreme bottom left corner has  NGC5169.  160mly away. And the small needle along the left downward diagonal is IC4263  — 140mly away. There’s also a neat double star in the extreme lower right corner — HIP 65664 A & B.

The companion smudge of the Whirlpool has its own designation,  NGC5194. If you maximally pixel-peep the area just above and to the right of NGC5194, the galaxy IC4277 is a barely discernible elongated smear:

close crop showing IC4277
A close crop showing IC4277 dead center

M51 is about 23 million light years away. As best as I can find, IC4277 is about 10 times as far — say 230 million light years.

About 6 hours total exposure time over three nights with a 115mm telescope.  Processed with PixInsight and GIMP.

Different views of M33

M33
M33 — pollution filter, half an hour total, good seeing
M33
M33 — nebula filter, two hours total, medium seeing

The sky here at Songbird Central suffers heavy pollution, both light pollution and chemical pollution. Astrophotography would be unsatisfying without filters to reduce the effects of that pollution.

I’ve forgotten exactly which filter it was I used with the first photo — I think the “Optolong L-eNhance”. A good general purpose filter. The image is dim, but if you look closely and carefully, there’s lots of sharp detail.  A stack of 30 one minute exposures, for half an hour total.

The second photo was taken with the “Triad Ultra” filter, which emphasizes the light from nebulae, a stack of 13 three minute exposures and 17 five minute exposures — a little over two hours total. In this image the white light from the stars has been reduced, while the red light from the glowing gas areas is emphasized. The image is redder, overall, and there are many tiny reddish fuzzy blotches, which are nebulae within M33.

How does M33 really look?   Photos are stories, not truth. If you were a lucky human with opportunity to look at M33 through a big enough telescope, you might see something like the first picture, but not the colors in the second.  If you really got into it, you would recognize the overall shape of the galaxy, and you might even recognize details in the patterns of the stars.

[Edited to adjust the scale and other corrections.]

Unavoidable Noise

M101, the “Pinwheel Galaxy”.  It has low surface brightness, and the sky at Songbird Observatory, San Francisco East Bay Hills, is almost always at least a little hazy, with an ever-present skyglow from the nearby cities. The results are always  noisy –like an analog photos with lots of grain:

M101 -- full noise

Further processing with PixInsight and Gimp lessens the obvious noise, but you also lose some of the delicate shading in the galaxy:

M101 with more processing 

I can’t see this object (it seems so strange to use the word “object” to refer to an entire galaxy…) with my naked eye.

In fact, most nights I can’t make out more than a couple of constellations — if I didn’t use software to point the telescope, I would not be able to find M101.

How, then, do I even know this is M101 I photographed? I can compare it with the Hubble view.

The Crab

Last night waves of wispy clouds kept flowing across the sky. I pointed the telescope at M1, the Crab Nebula, and took a 2 minute exposure. Not much, but more than I expected:

crab through cloud

So I set the scope for 30 2-minute exposures, and went away to dinner.

But apparently after 5 crummy shots like the above, the sky cleared for a short window, and the remaining 25 were good. Unfortunately clouds returned, along with a heavy mist, so I covered the scope for the night.

Here is the sum of the 25 shots:

cCrab Nebula through thin clouds

It looks more like a brain than a crab.  Maybe a crab without legs? But turquoise and gold on black velvet, at least. If it’s clear tonight I’ll add more exposures.

The Skull Nebula

The weather has been inclement and overcast for weeks now, with only a few clear nights.  It’s been so long that I have had trouble getting my telescope set up.  Here’s an image I call “The Skull”.  Really the Rosette Nebula, but this view, to me, looks like a distorted skull gazing wistfully off and up to the right.

The Skull

Many years ago I was on a rafting trip through the Grand Canyon. Floating through the Inner Gorge you can see Vishnu Schist worn by the water into beautiful fluted black walls. But I, in a grim mood, thought of that schist as the tortured souls of the damned, souls that had been sent back in time (God could do that, right?), buried miles deep and burned for eons by the molten interior of the Earth, crushed and twisted beyond all recognition and buried for millions of years until they were for a brief instant exposed to the sun and air and water, so I could see them as I floated by.

Anyway, the Skull Nebula.

Monochrome

I recently acquired a monochrome astro camera with somewhat higher resolution.  Here are a few attempts:

M42 - Orion Nebula
The tight cluster of 4 stars at dead center is known as the “Trapezium Cluster”. It’s barely resolved in this image.
M33 in Triangulum
M33. Low surface brightness, but if you look closely, there is a lot of detail.
Horsehead-Flame nebulae
Horsehead Nebula — I like this image. The Horsehead is an object I find intrinsically beautiful.
The Heart Nebula
The Heart Nebula. Upside down from the usual view.
Wide view of Orion, processed for low brightness
Fairly dim view of the Orion Nebula. Looks like a landing bird, or maybe a falling angel. The Trapezium is discernible on zooming in.
The Pleiades
The Pleiades. Light reflecting off a dust cloud, usually a beautiful blue.

M42

The Orion Nebula
Originally a color shot, but it looked better in black and white.

Alnitak

The Horsehead
Alnitak is the bright star a little lower right of center.

Orion is back… Interestingly enough, at this angle the Horsehead Nebula is a decoration on the back of a much larger horse running off to the lower right.  At least it looks that way to me.

My first recognizable photo of the Horsehead was taken about a year ago.  It is amazing what better equipment and tools will do.

Cocoon

The cocoon nebula — IC5146

“My precious…”