Oh Yeah Speaking Of Grass.

Photo of the Iris nebula / Caldwell 4 / NGC 7023, I'm very pleased with this one since I finally managed to capture the surrounding dust (barely visible in the 2 previous attempts). This is a reflection nebula, this means that it's a dust cloud reflecting the light from a nearby star. Being one of the brightest reflection nebula visible in the northern hemisphere it's visible in relatively small telescopes (4-6 inch / 100-150mm diameter), unfortunately the outer dust clouds can only be seen on photos. Reflection nebula generally tend to be blue due to a more efficient scattering of blue light compared to red by the dust particles (M45 in my previous post is another good example).

Finale got around to processing the photos of M33 I had taken at the end of august. M33 is a spiral galaxy about half the size of our own galaxy and located about 2.7 million light years from earth. This galaxy has a rather high rate of star formation resulting in numerous ionised hydrogen regions (the red irregular blotches inside the galaxy), some of those being notable enough to have been included in the NGC catalogue or the IC catalogue.

NGC 588 NGC 604 (Example of some of the notable nebula in M33)

On of the first recorded observation of this galaxy was possibly done by Giovanni B. Hodierna before 1654, it was independently rediscovered by Charles Messier in 1764 who added it to his catalog (hence the name Messie 33).

information on the photo - total exposure time : 1h48 min using RGB and Ha filters - camera : ASI294 mm - telescope : Newtonian 150/600 with 0.95x coma corrector - photo edited with pixinsight

For those using PixInsight for treatment/edition, I recently discovered the scrips created by Seti Astro (https://www.setiastro.com/pjsr-scripts), Blemish-Blaster was quite useful to remove the halos from my Ha filter and What's In My Image helped with the identification of nebulas. If you had not heard those scrips, you should check them out.

Photo of Pickering's triangle (also known as Fleming's triangle) and NGC 6979 / NGC 6974 (the more diffused clouds at the top center/left). This is the third part of the Cygnus loop / veil nebula, this part of the supernova remnant is fainter than the previous two parts of the loop I photographed. This explains in part why it was only discovered by in 1904 by Williamina Fleming (whereas the two writer part were discovered in 1784 by William Herschel). Williamina Fleming was a pioneer in stellar classification, she worked with other women at the Harvard college observatory. Their work in star classification resulted in the Henry Draper Catalogue, an extensive (225 300 stars in the first edition) classification of stars with their position and their spectra. Williamina is also credited with the discovery of 59 nebula (including the famous hors head nebula) more than 300 variable stars as well as (with Henry Norris Russell and Edward Charles Pickering) the discovery of white dwarfs (the remnants of dead sun-like stars).

Picture of M27, the Dumbbell nebula (aka the Apple Core Nebula), I took at the end of last month. This is a planetary nebula, it's the result of a star similar to our sun, that had turned into a red giant at the end of its life, ejecting its outer layer of gas and plasma into space. A planetary nebula is probably a relatively ''short'' phenomena, lasting around 10 000 years. Once the central star has ejected most of its hydrogen/helium and that the nuclear fusion in it has stopped, the nebula will start to cool down and disappear while the star turns into a white dwarf. Planetary nebula have an important role in redistributing some of the matter from dead/dying stars in the interstellar medium.

I personally think that photo is good, but some of the more faint external structures are barely visible, might take another picture of it and/or more photos to stack later in the month.

So I just saw a post by a random personal blog that said “don’t follow me if we never even had a conversation before” and?????? Not to be rude but literally what the fuck??????????

I’ve had people (non-pornbots) try to strike conversation out of nowhere in my DMs recently, and now I’m wondering if they were doing that because they wanted to follow me and thought they needed to interact first. I feel compelled to say, just in case, that it’s totally okay to follow this blog (or my side blog, for that matter) even if we’ve never talked before.

Also, I’m legit confused. Is this how follow culture works right now? It was worded like it’s common sense but is that really a thing?

This is the heart nebula (or at least as much of it as I can take with my setup without doing a mosaic) also known as IC 1805 or NGC 896. It is around 7 000 light years from us, in the constellation Cassiopeia. Despite its distance to us it still appears about twice as big as the moon in the sky, which speaks volumes when it comes to its actual size (about 200 light years in diameter).

This being an emission nebula its light mostly comes from gasses ionised by nearby stars.

This nebula also has an open cluster at it's center (a bit closer to us than the rest of the nebula), Melotte 15:

This cluster is bout 1,5 million years old which is very young for such a stellar object. It is composed a a few very heavy and bright stars and many fainter lighter stars.

The starless version :

(Image taken using a CarbonStar 150/600 newtonian telescope with a 0.95 coma corrector, ZWO ASI294 monochrome camera and Baader 6.5nm narrowband filter. 25x300s for the Ha filter, 26x300s for the SII filter and 26x300s for the OIII filter, total imaging time 6h 25min, stacking and processing done in PixInsight. Photo taken mid-January) Other versions with a different colour combinations (a bit less pleased of how they turned out).

If you want to see the nebula in its entirety, you can check out this NASA Astronomy picture of the day made by Adam Jensen.

Friendly reminder that CRT TVs were basically a particule accelerator you had in your living room. They used power supple capable of delivering tens if not hundreds of thousands of volts, to accelerate the electron that were quite literally being boiled of a glowing piece of metal.

They sometime used a lead infused glass as the front plate to limite if not eliminate the small amount of X-ray they emitted towards you.

They had to be heavy because of the thickness of the glass needed to resist the distance of pressure between the atmosphere and extremely low vacuum inside the vacuum tube. It's that difference of pressure that would result in them exploding in a shower of glass shrapnell if the tube was broken.

Finished working on my photo of the hors head.

Technically speaking the Horse Head is only the dark nebula, is bright hydrogen cloud behind it is known as IC434 and the second nebula (bottom left) is the flame nebula. The bright star in the center left is Zeta Orionis also known as Alnitak one of the three stars of Orion's Belt. IC434 primary ionisation source is the multiple star system Sigma Orionis (a bit above the frame), the hydrogen cloud being mostly ionise by the UV coming from those blue giant stars. The streaks visible in the nebulosity are mostly likely due to magnetic field within.

The Flame nebula's ionisation source is hidden behind it's dust cloud and is most likely part of a star cluster that Is only reviled using IR and X-ray imaging.

This photo appears mostly blue/teal wear-as most photos of this nebula are red(ish) this is because this nebula emits most of it's light in the H-alpha (656 nm) and S-II (around 672 nm) wavelength both of which are red, so in classic RGB images the nebula appears red. Initially I thought of doing an SHO image (were red is SII emission, green is H-alpha and blue is OIII) but this nebula lacks OIII emission (around 500 nm), so instead a used a modified SHH palette More precisely, I used SII for the red, a combination of both Ha and SII (0.8Ha + 0.2SII) for green and Ha for blue. The stars were taken separately in RGB and added back to the SHH image.

(Image taken using a CarbonStar 150/600 newtonian telescope with a 0.95 coma corrector, ZWO ASI294 monochrome camera and Baader 6.5nm SHO filter. 5x120s image for each colour filter (RGB), 22x300s for the Ha filter and 32x300s for the SII filter, total imaging time 5h, stacking and processing done in PixInsight.)

Image of IC 405 aka the Flaming Star Nebula This is an emission (the red part) and reflection (the blue part) nebula. It's relatively bright for a nebula with visual magnitude of +6.

The bright star at the center of the blue reflection nebula is AE Aurigae, it's the star responsible for the ionisation of the gas in this nebula. AE Aurigae is what's known as a runaway star, those are star that moves at high speed compared to their surrounding environment. They are the result of gravitational interaction between stars or stars being ejected by nearby supernovae. In the case of AE Aurigae, it was probably ejected due to gravitational interaction, its path has been traced back to the Orion Nebula from which it was ejected about 2 million years ago.

The moon was nearly full and somewhat close by when I took the photos, so it was a bit tricky to process them. As a result, the reflection part of the nebula was not as visible as I would have liked but I think the overall result is not too bad.

Image taken using a CarbonStar 150/600 newtonian telescope with a 0.95 coma corrector, ZWO ASI294 monochrome camera. 6x300s image for each colour filter (LRGB) and 12x300s for the Ha filter, total imaging time 3h, stacking and processing done in PixInsight.

Tried applying the Ortonglow script in PixInsight to give the nebula a bit more depth, but I don't like the halos it gave around the bright stars on the left.

Those do not look like much, but they are, to the best of my knowledge, Herbig-Haro object (to left: HH 94, top right: HH 249 and bottom: HH 95) Herbig-Haro object are ionised gas clouds formed when the jet of hot plasma ejected at the poles of newly born stars interacts with Interstellar gas, they are thus more common in star forming regions. I first noticed one of them (HH 94) after I shared the image with a friend. The What's in my image PixInsight scrip from SetiAstro was very useful in finding out what that was. I couldn't find a lot of information on those objects specifically (and very few pictures), but a few publications did have images to compare with (orientation differs):

(original publication ref for HH 94 & HH 95; additional publication ref for HH294 aka NGC 2023 HH 3) (better images of other Herbig-Haro object taken by Hubble : 1, 2 & 3) Position of the three objects in the original image (another might be present but I wasn't confident they were visible):