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First Mars

MarsFirst attempt at Mars under poor seeing. I’m pretty happy with the little bit of surface detail I was able to get here and learned a lot in the process for next time. 

Sol

SolFirst light with the new solar scope. This was imaged with an inexpensive 2x Barlow, so I’m curious if some of the fringing is from that or user error. I’d like to practice again when it cools off some. As soon as I set up, the clouds started rolling in. LOL.

Jupiter – 2nd attempt

5x Barlow

I made another run at Jupiter last night. Mistakes were made.

Most of the data I accumulated during my session prior to transit is not usable in any way. Well, I did make a little GIF of the planet rotation that I’ll put in the comments, but basically it is mush. My plan poorly executed was to image through a 5x barlow to stretch the limits of the equipment I could bring to bear, but the gas giant remaining at low altitude (less than 37° at transit) and poor atmospheric seeing made this unrealistic. Every turbulent thermal mixing and tiny gust of breeze is amplified massively when shooting in this configuration. I took a series of 9 imaging runs with the barlow in place where I had planned to measure and derotate the result of each set and then stack them together. /sigh This is how we learn.

Fortunately, I did a single series after removing the 5x barlow with the native OTA and only an ADC (Atmospheric Dispersion Corrector) in-line with the planetary imaging camera. I tried to calibrate with the ADC, but the conditions were just too poor to get a good delta, so consider its use inconsequential for this image. This is the best half (ranked and weighted) of 10,000 frames imaged at 2350mm f/10, pre-processed/centered, debayering, image registration, deconvolution, and wavelet transformation applied, cropped and color adjusted. You can see (in order from left to right) Io, Europa, and Ganymede in frame, but Callisto was just out of frame to the right. I haven’t really figured out how to expose for the planet and the moons at the same time, but maybe people do the moons separately and then create a composite. Something for another day.

I still want to map and derotate a series of images over a longer acquisition window to see how that improves surface detail, but I think I’ll do it next time without any optical attachments to get practice with the post-processing workflow. It feels bad to throw away data… because that represents time invested that could have been used productively on something else. I do want to image with additional magnification and with a higher resolution sensor, but those are pushed down the priority list at this point.

Practice, practice…
Jupiter

 

Finally, Jupiter.

JupiterI’ve never attempted to photograph this gas giant… our largest planet. It had been so long since I tried to take a picture of a planet that I really wasn’t sure I’d remember the steps. The planet was set to transit around 10:45pm at around 37° altitude, so the seeing was challenging despite being a beautiful night. You can see (left to right) Io, Europa, and Ganymede visible in orbit… these are 3 of the more well known siblings of Jupiter’s 79 moons. Fun fact: Ganymede is the largest moon in our solar system. I’m looking forward to trying this again when Jupiter and Saturn are higher in the sky, but I’m pretty ok with this first attempt!

Pinwheel a Go Go

It’s been 498 days since I pointed a camera at the sky… that’s over 16 months! This was a great reminder that astrophotography is a proficiency-oriented hobby… and I’m really out of practice. Last week, I decided I would try and get back on the horse and barely missed getting pummeled by a surprise hailstorm after all data pointed toward what should have been a clear night with great viewing. Yesterday was windy, but the forecast looked good again… and although the moon was more prevalent in phase, it was scheduled to set fairly early. I didn’t have as much issue with setting the rig up since I’d been through that evolution last week and worked through the process. I didn’t have too much trouble with polar alignment and calibration, but did stumble a bit during the star alignment of the equatorial mount. Focusing the imaging and guide scope took longer than it should have and I neglected to refocus the imaging scope between each filter change, so that resulted in out-of-focus subs. I really, really don’t like out of focus stuff. Perhaps a bit aggressive for being so out of practice, I decided to run 600 second subframes for each channel. I actually took an hour of Hydrogen Alpha subs, but ironically have completely forgotten how to integrate them into my red channel, so I need to go read up on that again. I also did not have any 600 second calibration data, so I had to set up the camera and run darks this morning while I worked. I didn’t grab enough subframes per channel for the usual Windsorized Sigma Clipping integration I use, so I had to use Percentile Clipping and felt like I was winging it. After managing to get the light frames calibrated and registered to each other, I fumbled through RGB integration, then added the Lum channel with a smaller set of the images I’d taken because I tossed over an hour of out-of-focus luminance subs. Overall, this image of M101 is littered with technical problems… focus, noise, insufficient color data, color calibration of starfield, and the list goes on, but I’m pretty happy to get at least something pulled together after nearly a year and a half out of practice. This image as shown is comprised of 24 subs split fairly evenly over red, green, blue, and luminance channels… so about 4 hours of data (sans Ha). The night was nice and other than being a little chilly (I layered up), it was relaxing to sit under the stars and listen to the wildlife. There seemed to be less air traffic due to the pandemic in effect, so that was a little silver lining that helps when you are leaving the shutter open for 10 minutes at a whack. At any rate, it’s clear some more practice is in order. Hopefully, I can make that happen sooner rather than later.

“The Pinwheel Galaxy (also known as Messier 101, M101 or NGC 5457) is a face-on spiral galaxy distanced 21 million light-years (six megaparsecs) away from Earth in the constellation Ursa Major. Discovered by Pierre Méchain on March 27, 1781, it was communicated to Charles Messier who verified its position for inclusion in the Messier Catalogue as one of its final entries. M101 is a large galaxy, with a diameter of 170,000 light-years. By comparison, the Milky Way has a diameter of 100,000 light years. It has around a trillion stars, twice the number in the Milky Way. It has a disk mass on the order of 100 billion solar masses, along with a small central bulge of about 3 billion solar masses. M101 is asymmetrical due to the tidal forces from interactions with its companion galaxies. These gravitational interactions compress interstellar hydrogen gas, which then triggers strong star formation activity in M101’s spiral arms that can be detected in ultraviolet images. It is estimated that M101 has about 150 globular clusters, the same number as number of Milky Way’s globular clusters.”

M101 in LRGB
M101 in LRGB

Back in the saddle with 46P/Wirtanen

“The Christmas Comet” is in Taurus and likely as close as it’ll be to Earth for at least another 20 years. The best night to view the comet was Saturday (12/16) where it achieved the closest point of it’s pass at about 7.1 million miles over Tranquility Base. We were at a neighborhood Christmas parade and party that night and it’s been overcast since. Last night looked to be the next available window, so I blew the dust off my brain and set up to hopefully take a photo. Well, if there is one consistency in this hobby, it is that challenges arise. There was tremendous (albeit beautiful) spotty cloud coverage for the first several hours after sunset… but that wasn’t the rub. The moon was SO bright that polar alignment was tricky and imaging in full band was going to be a problem. My goal from the start was to try to get the comet and M45 in the same frame, so I pressed on with what I’d already set up and crossed my fingers. It was quickly clear to me that I wasn’t going to pull off anything close to my attempt at C/2011 W3 (Lovejoy) in 2015, so I decided to try something completely new to me… an animated image. So yes, there is not much to speak of in terms of capturing a magnificent coma or nebulosity around Pleiades, but you do get three hours of the comet’s journey through our solar system… from 9pm to midnight last night. Cheers!

Comet 46P/Wirtanen is a small short-period comet with a current orbital period of 5.4 years… meaning it swings on by us every five and a half years. It belongs to the Jupiter family of comets, all of which have aphelia between 5 and 6 AU. Short period means it’s orbit is less than 20 years and “Jupiter family” is just saying that it’s orbit is dictated/controlled by Jupiter’s gravitational field (aphelia is the maximum distance it gets from it’s controlling body). Its diameter is estimated at 1.2 kilometers, so almost three-quarters of a mile at it’s widest bits. 46P/Wirtanen was discovered photographically on January 17, 1948, by the American astronomer Carl A. Wirtanen. The plate was exposed on January 15 during a stellar proper motion survey for the Lick Observatory. Due to a limited number of initial observations, it took more than a year to recognize this object as a short-period comet. You can still see it if you have any interest as it is quite bright at the moment. If you are near any form of light pollution, you’ll probably need some binoculars to find the feint fuzzy traveling 83,000 mph overhead.
46P/Wirtanen

North American revisited.

It’s been a long dry spell since I imaged. I think I made an attempt a few months ago in early May and just didn’t have any decent results… before that, it was January. While we just finished a stretch of poor weather surrounding the hurricane, the skies, albeit moon-filled, were clear last night. So, with cool air and an idea, I set out to image the Heart and Soul nebulae together in a 200-ish mm focal length with one of my DSLR lenses. I’d like to try and recreate the pair imaged in narrowband with those nice blue and gold hues that I find so elusive in post. When I was set up and polar aligned, I realized that the targets would be behind some tall pine trees for another couple of hours… comes with the territory living in the piney woods of east Texas. I didn’t want to simply wait it out without any production what-so-ever, so I started mentally running through other larger targets that might be suitable for that focal length and that were also high enough above the horizon to get a clear field of view. I’ve done a really wide run at the North American Nebula before (I think it was about 70mm), but why not practice on it again with a different framing, right? So I spent the hour or so before its transit gathering hydrogen-alpha data in 10 minute un-binned subs. I thought 10 minutes would be safe given the significantly lighter loading on the mount with no telescope, but being extended near the meridian flip caused some tracking issues that resulted in rice-y stars. After the flip, I got about 10 or so subs each of OIII and SII (binned 2×2 for signal) before imaging some new Ha subs with better star shape. I ended up using all the Ha anyway (minus one with a pine treetop in frame), but I’m sure the image could be marginally improved by throwing away everything before the transit. I am still not where I want to be on the colors/hues in my Hubble palette attempts, but I’m getting closer. I ended up sticking with NGC 7000 the rest of the run and decided to save the Heart and Soul project for another day (night).
 
What am I looking at here? Well, all this stuff is in Cygnus. Cygnus (the swan) is a large northern constellation that is in the plane of our Milky Way… meaning, when you are somewhere dark and can see the milky-band of our galaxy, it’s in that stuff. The most prominent target in this image is NGC 7000 – which is commonly known as the “Norht American nebula” due to its pseudo-resemblance to the North American continent. The little section that would be where the Gulf of Mexico coast of Texas is in the nebula is one of the most photographed parts of the entire contellation… it is known as “the Cygnus Wall”. Next to the North American nebula is IC 5070 – the Pelican Nebula. Both the North America nebula and the Pelican Nebula are emission nebula and active star-forming regions. The North American Nebula is approximately 520 parsecs (1,700 light-years) from the Sun. It has a diameter of about 100 light-years and a total mass equal to about 4,000 solar masses. It is so large that it is viewable with the naked eye from some of the darkest places on Earth. The region of Cygnus shown in this image is packed full of all sorts of other stuff, but those are the two most well-known characters. 
NGC 7000
The North American Nebula

IC 1396 – The Elephant’s Trunk nebula in SHO

I had a lot of trouble with processing this in PixInsight and having it turn out looking like the SHO renditions I’ve seen floating around the Net. I ended up using Don Goldman’s tutorial on using Hue/Sat adjustment layers and clipping masks in Photoshop, but I really would like to find some native PI techniques and reprocess it without having to fiddle with it in PS CC. This is 90 minutes per narrowband channel – so not a lot of data, but it was all I could get before the nebula hit the pine tree tops lining the imaging location. Practice is a good thing, though… 
The Elephant's Trunk