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A very crisp and cold night. I added more luminance data and also collected some RGB for NGC 2841. There is now around 4 hours in L and an hour each in R, G and B. The subs are 114s at a gain of 139.
NGC 2841 is an unbarred spiral galaxy in the northern circumpolar constellation of Ursa Major. A 2001 Hubble Space Telescope survey of the galaxy's Cepheid variables determined its distance to be approximately 14.1 megaparsecs or 46 million light-years.
This is the prototype for the flocculent spiral galaxy, a type of spiral galaxy whose arms are patchy and discontinuous. The morphological class is SAa, indicating a spiral galaxy with no central bar and very tightly-wound arms. There is no grand design structure visible in the optical band, although some inner spiral arms can be seen in the near infrared.
The properties of NGC 2841 are similar to those of the Andromeda Galaxy. It is home to a large population of young blue stars, and a few H II regions. The luminosity of the galaxy is 2×1010 M☉ and it has a combined mass of 7×1010 M☉. Its disk of stars can be traced out to a radius of around 228 kly (70 kpc). This disk begins to warp at a radius of around 98 kly (30 kpc), suggesting the perturbing effect of in-falling matter from the surrounding medium.
The rotational behaviour of the galaxy suggests there is a massive nuclear bulge, with a low-ionization nuclear emission-line region at the core; a type of region that is characterized by spectral line emission from weakly ionized atoms. A prominent molecular ring is orbiting at a radius of 7–20 kly (2–6 kpc), which is providing a star-forming region of gas and dust. The nucleus appears decoupled and there is a counter-rotating element of stars and gas in the outer parts of the nucleus, suggesting a recent interaction with a smaller galaxy.
Equipment: Celestron 9.25 XLT at F10, Skywatcher EQ6 Pro GEM, ZWO 1600MM Pro, ZWO EFW with ZWO LRGB filters, QHY5IIC guide camera on Skywatcher 9 x 50 finderscope
Who knew renovating a house could take so long - and it's still a long way from being finished (maybe I shouldn't have tried to tackle it all myself...)
But having finally uncovered some of the boxes containing my kit, and with a bit more free time than normal, I decided to have another go, starting with one of the top targets this time of year. (I am working from home, honestly).
I felt like I was learning again from scratch. But at least I've discovered the masked stretch. This image might be over-saturated for some tastes, but what can I say, it's the first time I've managed to get any colour in my
20x10 mins L
Altair Astro Wave 115 refractor, SBIG STF8300M, GM1000HPS (never managed to get it to track unguided, but at least it can be guided now)
Celestron 9.25 at f6.3, SW EQ6R pro, Canon 550 D modded
The galaxy group Hickson 44 in Leo. This is based on 29 x 240 s, plus bias and flats.
Hickson 44 in Leo:
There are some other galaxies near by, some of which are names in this overlay from Astrometry.net:
Overlay from Astrometry, naming the other objects:
The main ones are NGC 3190, NGC 3185, NGC 3187 and NGC 3193. NGC 3190 has a well defined dust lane. NGC 3187 is a barred spiral galaxy with two arms. NGC 3193 is an elliptical galaxy.
The light captured by my camera last night left these galaxies just after the extinction event killed the dinosaurs on Earth.
From APOD: Galaxies, like stars, frequently form groups. A group of galaxies is a system containing more than two galaxies but less than the tens or hundreds typically found in a cluster of galaxies. A most notable example is the Local Group of Galaxies, which houses over 30 galaxies including our Milky Way, Andromeda, and the Magellanic Clouds. Pictured above is nearby compact group Hickson 44. This group is located about 60 million light-years away toward the constellation of Leo. Also known as the NGC 3190 Group, Hickson 44 contains several bright spiral galaxies and one bright elliptical galaxy on the upper right. The bright source on the upper left is a foreground star. Many galaxies in Hickson 44 and other compact groups are either slowly merging or gravitationally pulling each other apart.
This image is based on 19 x 300 s , plus flats and bias. It shows a LOT of galaxies, in a grouping called Abell 1367. In this image you are looking at part of one of the biggest structures in the Universe, the Great Wall.
The Leo Cluster (Abell 1367) is a galaxy cluster about 330 million light-years distant (z = 0.022) in the constellation Leo, with at least 70 major galaxies. The galaxy known as NGC 3842 is the brightest member of this cluster. Along with the Coma Cluster, it is one of the two major clusters comprising the Coma Supercluster, which in turn is part of the CfA2 Great Wall, which is hundreds of millions light years long and is one of the largest known structures in the universe.
The overlay from Astrometry gives some of the galaxies visible in the image.
This will be my last image this season. The moon is all too bright atm, and astro darkness ends in a few days.
This image was a real challenge, both in acquisition and in processing. I haven't completely tamed the MN190 yet, collimation is still a bit off. Visually it looks ok, but when I start imaging, I get star shapes that suggest that collimation is still way out. First I thought that it might be the addition of an oag to the imaging train that was the cause of it all, but I've now come to the conclusion that it actually is collimation.
Anyways, the details:
MN190 on AZ-EQ6 ZWO ASI174MM-Cool at -20 C with ZWO filters Guiding was a mixture of ST80 guidescope, OAG (the new ZWO version), and finder guider (9x50) with PHD2 L. 92 x 2 minutes, gain 20, collected April 15 under a 70 % moon R, G: 30 x 4 minutes each, collected March 31 and during two nights in April B: 22 x 4 minutes, collected March 31 and during one night in April Processed in PixInsight
Larger version is here:
If anyone wants to have a go at LRGB processing, here's the raw data. Only crop and DBE applied. Have fun!
So I was out the other night collecting images for a star trails of Ursa Major over the top of my daughter's tree in the front garden. Out of curiosity more than anything, I thought I'd give time lapse a shot. The attached is low res as I'm still messing around with what codec etc works best. The original avi file was pushing 8gb for 7 seconds!! Managed to get it down to 22mb but can't find anything inbetween. I'll keep playing though.
Original raw files cleaned up in Lightroom, then exported out as Jpg's into After Effects. The trails image used the same Jpg set but was put together in Star Stax. As pretty much first attempts at both, I'm happy.
Nikon D5300, 18mm @ f / 3.5, ISO 800, 162 x 25 seconds
Millie's Tree & Ursa Major Timelapse Test.avi