My Favorite Galaxy!

Melinda was off last night, and the monsoon weather continues on hiatus, so we again headed to Kitt Peak National Observatory to catch some early Perseid meteors.  Since it was a "school night", we couldn't stay too late, but since she has to work on Monday night, the peak of the annual meteor shower, better to catch some than stay home and miss most if not all of them!

The Nightly Observing Program had been cancelled, since the forecast had called for a chance of rain, so we arrived to an empty parking lot, though all the "Big Boy" professional telescopes were open and working.  Like the other night we set up in the lot since it had pretty good horizons - not too much obstructions from the nearby trees or hills.  Melinda was only interested in the meteors, so set up a chair for visual lookin' and I again set up the tracking platform for some wide-field photography.  My hope, of course, was to capture a few meteors, but other than that, didn't have much of a plan. 

The waxing crescent moon was still above the horizon, but with it only 4 or 5 days past new, didn't much diminish the Milky Way Galaxy transiting almost due south.  In fact, the little bit of moonlight lit up the domes on the south ridge of the Observatory enough to let them stand out with the galaxy center shining down.  The image at left is a single exposure with the Canon XSi and Nikon 16mm fisheye at F/2.8.  I used the tracking platform at the half-speed rate so that the blur would be spread out between star and horizon to allow a little longer exposure.  This one is 90 seconds at ISO 1600 with in-camera noise reduction on.  The dome to the left is the 2.1 meter, and at right center is the WIYN 0.9 meter telescope.  The row of red lights at the bottom are to guide NOP guests to the rest rooms.

While taking the above exposure, I got a wild idea...  With the ease of making the panorama the other night of the Prancing Horse Nebula, I wondered how wide-field shots of the Milky Way could be put together for a portrait of our galaxy.  I chose another Nikon lens, an older 20mm F2.8 from my film days, and started down near the southern horizon.  I shot 4 or 5 exposures of 3 minutes each to stack and reduce noise, then moved north a good part of the frame, allowing a little overlap for software to assemble the panorama.  Of course, with meteors whizzing across the sky, if I happened to catch any of them, all the better!  In fact, I caught only one - a pretty bright one we saw zipping just above Cygnus, shown at left.  Deneb (alpha Cygni) is the bright star just right of center, with the North American Nebula just below left of it.  While only capturing the one meteor, we saw 43 Perseids in 3 hours of looking, and also saw about a dozen from the Delta Aquariids and Anthelion radiants as well as some sporadic, random meteors that we didn't include in our totals.

So anyway, I ended up shooting 6 frames with the 20mm, 4 or 5 exposures of 3 minutes each.  Coverage pretty much went from the southern horizon to below Cassiopeia near the northern horizon, though some thin clouds or haze, lit up by Tucson and Phoenix had me cropping out some of that section.  Amazingly, Photoshop had no issues with assembling the star exposures.  My only issues were with data reduction...  I shot raws as well as jpegs, also took the occasional dark frame to subtract electronic noise.  I first reduced the raws, subtracted the darks, reconverted to color, then stacked and assembled the panorama.  Unfortunately, this version was difficult to make the Milky Way look realistic.  The fainter sections looked very much like the brightest sections, so I went through it all again with just jpegs, without dark subtraction.  Since the blog limits me to 1600 pixels wide anyway, you can't see any sign of the hot pixels anyway...  And this version looks much more realistic, and the dark nebulae structure scattered through the plane of the Galaxy looks quite amazing!  Absolutely click on the image to see the full-size version.  I've seen a few impressive pictures of distant edge-on galaxies, but here you can see my favorite galaxy, assembled from images taken with a 20mm lens in less than 2 hours of exposure! 

And while the pixel limit really cuts down on what you can spot, you can easily pick out the Andromeda Galaxy at the lower left corner.  Of course the Prancing Horse dark nebula is seen to the lower left of Antares at the far upper right.  And the Summer Triangle of Vega, Deneb and Altair can be seen near the center.  Perhaps I'll make an annotated version with labels, but it is a shame you can't see the 10,000 pixel wide image.  Anyway, enjoy!