Remembering Earth-that-was
This post is to celebrate my new skill, annotating an image.
Here’s M106 and a bunch of visually smaller galaxies:
(I should mention that these images should be viewed on a larger screen.)
And, presto, here’s an annotated version showing the named galaxies:
This is SO nifty.
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:
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.
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.]
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:
Further processing with PixInsight and Gimp lessens the obvious noise, but you also lose some of the delicate shading in the galaxy:
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.
Two nights ago the sky was clear and steady, and the telescope was working fairly well…
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:
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:
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 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.
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.
I recently acquired a monochrome astro camera with somewhat higher resolution. Here are a few attempts:
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.