Over my recent trip to Washington and Oregon (including the Oregon Star Party) the skies were cloudy at least half the time, and this time of year the nights are REALLY short up there. I like to collect a lot of photons from each target, so in this case I completed just 1 image; M101, the Pinwheel Galaxy.
This was done with a William Optics FLT-132 telescope (with 0.8X reducer) and QHY268m camera, which means that the field of view is much larger than most galaxies, so I chose the biggest one (after Andromeda). It would have been somewhat larger if I had not used the 0.8X reducer, but this device also provide field flattening, which is essential.
After discarding numerous bad frames, this image includes about 12 hours of exposure (over 5 nights).
M101 is about 21 million lightyears from Earth, in the constellation Ursa Major. Its diameter is more than double that of the Milky Way at 250,000 lightyears, and it contains about 1 trillion stars.
The Pinwheel Galaxy (M101)
08.07.2025 05:07 β π 1 π 1 π¬ 1 π 0
The Jellyfish Nebula (yellowish object in the lower right) is cataloged as IC 443 and Sh2-248. It is a supernova remnant (SNR), probably formed 30,000 to 35,000 years ago. It's about 5,000 lightyears from Earth, in the constellation Gemini.
This image was captured in my backyard observatory using a Stellarvue SVX80T telescope and QHY268m camera with narrowband filters. The color assignment is simple: Red is hydrogen, green is sulfur, and blue is oxygen. Yellow (red plus green) indicates both hydrogen and sulfur are present. It seems like there is very little blue (oxygen), but there is some around the edge of the jellyfish. It also "modulates" the color somewhat in the red nebula on the left.
The Jellyfish Nebula (and friends)
13.03.2025 22:10 β π 0 π 0 π¬ 0 π 0
The Cone Nebula is the small cone-shaped object at center left. The Foxfur is a little harder to pick out, but it at the right hand end of the pink/orange region near the center.
What was totally unexpected (by me, anyway) is that dark nebulosity to the right and slightly below center, and looking VERY much like a boar's head! As far as I can tell this has never been cataloged or named, although a small portion of it is cataloged as a Barnard's Dark Nebula. The bright spot in the lower left is Hubble's Variable Nebula.
In this version the stars have been removed.
This version includes the stars.
Cone & Foxfur Nebulae - and More!
03.03.2025 02:15 β π 0 π 0 π¬ 0 π 0
Located on the border between constellations Monoceros and Canis Major, about 3,600 light-years from Earth. While it does look like a bird to me, that mouth definitely suggests a raptor, not a seagull. And it appears that he is about to throw a fireball at something!
This is a narrowband, false color image, captured with a small telescope of just 80mm aperture. It is made up from 205 exposures of 4 minutes each, for a total of 13.7 hours.
Processed in PixInsight and Photoshop.
The Seagull Nebula, from Wachured Observatory.
27.02.2025 18:19 β π 0 π 0 π¬ 0 π 0
I just finished capturing images last night and did a quick processing of it this morning. This is only about 10 hours of exposure, but it's a fairly bright nebula, so a lot of detail is already apparent.
The Rosette is cataloged as Caldwell 49, and contains several small star clusters that are in the NGC catalog. Both the nebula and clusters are about 5,000 lightyears from Earth.
This is a narrowband image, captured with H-alpha, Sulfur-II, and Oxygen-III spectral line filters. These filters tend to suppress the star brightness, and they are further suppressed by separating the star image and processing it separately. When viewed directly through a telescope you would see a lot of stars and very little nebulosity. In particular, our eyes don't see dim red very well, so only the blue-green portion (which corresponds to oxygen) would be seen.
The Rosette Nebula in Monoceros, from my backyard observatory.
08.02.2025 20:53 β π 0 π 0 π¬ 0 π 0
Cataloged as NGC 2359 and Sh2-298, this is an emission nebula that was likely formed from the Wolf-Rayet star WR7 in a pre-supernova event. It is rich in hydrogen and oxygen, with a much smaller amount of sulfur.
I was surprised to find that the H and O images were very similar. To enhance the separation between the elements I started with a standard SHO->RGB (with a bit of H mixed in with the S), then applied a mix of H and O as luminance.
This image was composed from roughly 10 hours of exposure, with another 5 hours of data being discarded, mostly due to poor seeing.
Thor's Helmet: Somehow, I've never imaged this target before.
31.01.2025 05:39 β π 1 π 0 π¬ 0 π 0
IC 63 (also cataloged as Sh2-185) is a hydrogen region near the gamma star in Cassiopeia, which is the center star in the W shape of the Cassiopeia constellation, and the bright star in the upper left of this photo. Although they are often photographed together, IC 63 is just the brighter structure near the center of this photo, while the structure to the left is IC 59.
This hydrogen region is about 10,500 lightyears from Earth, while Gamma Cassiopeia is only 550 lightyears away.
This image was captured with narrowband filters for Hydrogen-alpha, Oxygen-III, and Sulfur-II spectral lines.
Cropped from the original photo, this close-up of IC 63 has the stars removed. Stars sometimes get in the way of enjoying the complex structure of a nebula.
My latest astrophoto: IC 63, The Ghost of Cassiopeia
25.01.2025 00:32 β π 1 π 1 π¬ 0 π 0
Astrophotography often involves a lot of cables, mostly power and data cables. This was the initial motivation for creating the Wachured Observatory Power*Star product for cabling at the telescope itself. But there can also be some benefit to organizing equipment and cables at the other end. Specifically, I've always put my power supply(s) in a waterproof box near the base of the telescope. My usage model has changed a bit, so I just rebuilt this "astro box". It contains a headless computer, a 12VDC power supply (which connects to the Power*Star box), a 48VDC power supply for the MyT mount, and a wifi router. There also a fan to keep it all cool.
This photo shows the inside of the box, with components labelled. As with Power*Star, Anderson PowerPole connectors are used (right side).
Whether at home or in the field, the power source is 120VAC. At the home observatory, this AC power comes from the house (through a UPS in case of power failure). In the field, it comes from a "solar generator".
For now, the fan is manually controlled, with 2 speeds. It could easily be controlled to provide a wide range of speeds using a PWM controller such as the WO Adim controller, but that would require some software development, so for now, it is manual.
The computer has its own wifi, of course, but when used in the field there is usually no network for it to connect to. It's possible to set up an adhoc network, but I find it easier to just add a small wifi router to create a network and serve as a DHCP host. At home, the computer can connect to my home wifi network, so the router can be turned off.
The box also supports different usage models for the computer's user interface: In the field it is strictly a headless computer that is monitored and controlled through a separate laptop or tablet using a remote desktop program. At home, an HDMI port is used for a monitor, and keyboard and mouse are connected via USB.
The field system consists of the "astro box" plus a so-called "solar generator". The solar generator produces both 120VAC and 12VDC, but the 12VDC connector is just a cigarette lighter jack, which is a horribly unreliable connector, so I power everything off 120VAC.
Latest astrophotography project: New "box" for computer and power supplies.
22.01.2025 22:57 β π 0 π 0 π¬ 0 π 0