Friday 29 May 2020

Pelican Nebula in Cygnus

This is based on 114s subs, around 60 mins in L,R, G and B. First time I have used the ZWO camera with the Skywatcher refractor.

Wikipedia:The Pelican Nebula (also known as IC 5070 and IC 5067[1]) is an H II region associated with the North America Nebula in the constellation Cygnus. The gaseous contortions of this emission nebula bear a resemblance to a pelican, giving rise to its name. The Pelican Nebula is located nearby first magnitude star Deneb, and is divided from its more prominent neighbour, the North America Nebula, by a molecular cloud filled with dark dust.

The Pelican is much studied because it has a particularly active mix of star formation and evolving gas clouds. The light from young energetic stars is slowly transforming cold gas to hot and causing an ionization front gradually to advance outward. Particularly dense filaments of cold gas are seen to still remain, and among these are found two jets emitted from the Herbig–Haro object 555. Millions of years from now this nebula might no longer be known as the Pelican, as the balance and placement of stars and gas will leave something that appears completely different.


Equipment: Skywatcher ED80 at F/7.5,  Skywatcher EQ6 Pro GEM, ZWO 1600MM Pro, ZWO EFW with ZWO LRGB filters, QHY5IIC guide camera on Skywatcher 9 x 50 finderscope

Thursday 28 May 2020

NGC 6946 Fireworks Galaxy in Cepheus

Subs of 114s, around an hour in each of L,R,G and B. Moon was around 4 days old and not a lot of astronomical night!


Wikipedia:
NGC 6946 (also known as the Fireworks Galaxy or Caldwell 12) is a face-on intermediate spiral galaxy with a small bright nucleus, whose location in the sky straddles the boundary between the northern constellations of Cepheus and Cygnus. Its distance from Earth is about 25.2 million light-years or 7.72 megaparsecs.

Various unusual celestial objects have been observed within NGC 6964. This includes the so-called 'Red Ellipse' along one of the northern arms that looks like a super-bubble or very large supernova remnant, and which may have been formed by an open cluster containing massive stars. There are also two regions of unusual dark lanes of nebulosity, while within the spiral arms several regions appear devoid of stars and gaseous hydrogen, some spanning up to two kiloparsecs across. A third peculiar object, discovered in 1967, is now known as "Hodge's Complex". This was once thought to be a young supergiant cluster, but in 2017 it was conjectured to be an interacting dwarf galaxy superimposed on NGC 6964.

Monday 25 May 2020

NGC 6888 The Crescent Nebula in Cygnus

The image is based on 114s subs, around 2 hours in each of L, R , G and B. Processed in DSS, PS and Lightroom.

APOD: NGC 6888, also known as the Crescent Nebula, is a cosmic bubble about 25 light-years across, blown by winds from its central, bright, massive star. This sharp telescopic portrait uses narrow band image data that isolates light from hydrogen and oxygen atoms in the wind-blown nebula. The oxygen atoms produce the blue-green hue that seems to enshroud the detailed folds and filaments. Visible within the nebula, NGC 6888's central star is classified as a Wolf-Rayet star (WR 136). The star is shedding its outer envelope in a strong stellar wind, ejecting the equivalent of the Sun's mass every 10,000 years. The nebula's complex structures are likely the result of this strong wind interacting with material ejected in an earlier phase. Burning fuel at a prodigious rate and near the end of its stellar life this star should ultimately go out with a bang in a spectacular supernova explosion. Found in the nebula rich constellation Cygnus, NGC 6888 is about 5,000 light-years away.




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

Thursday 21 May 2020

The Whale, Ring and Crescent

Losing the  (astronomical) night, so short on exposures. The Whale (NGC 4631) and the Creseent lack data to show decent images. The Ring has a LOT of data, but not enough to show the faint outer ring clearly. So, all work in progress I suppose.







Wikipedia:

The Ring Nebula (also catalogued as Messier 57, M57 or NGC 6720) is a planetary nebula in the northern constellation of Lyra.Such objects are formed when a shell of ionized gas is expelled into the surrounding interstellar medium by a star in the last stages of its evolution before becoming a white dwarf.

The Crescent Nebula (also known as NGC 6888, Caldwell 27, Sharpless 105) is an emission nebula in the constellation Cygnus, about 5000 light-years away from Earth. It was discovered by William Herschel in 1792. It is formed by the fast stellar wind from the Wolf-Rayet star WR 136 (HD 192163) colliding with and energizing the slower moving wind ejected by the star when it became a red giant around 250,000 to 400,000 years ago. The result of the collision is a shell and two shock waves, one moving outward and one moving inward. The inward moving shock wave heats the stellar wind to X-ray-emitting temperatures.

NGC 4631 (also known as the Whale Galaxy or Caldwell 32) is a barred spiral galaxy in the constellation Canes Venatici. This galaxy's slightly distorted wedge shape gives it the appearance of a herring or a whale, hence its nickname. Because this nearby galaxy is seen edge-on from Earth, professional astronomers observe this galaxy to better understand the gas and stars located outside the plane of the galaxy.

Tuesday 12 May 2020

Comet 2017 T2 Panstarrs

This is the result of  12 x 60s subs in each of luminance, red, green and blue light. There was a 10 sec pause between each image to give more time for the comet to move (requirement for the processing technique). According to the method I was following, the total data time should be under an hour because comets are such dynamic objects
I was trying to follow Bernard Hubl's method but in the end had to use Deep Sky Stacker and its 'comets and stars' function. 
For Luminance  I produced an image of the comet only.
For R, G and B I produced an image of the comet plus stars. The channels were combined in PS
I stretched both the L and the RGB images in PS and then combined them. 
 The trouble I found with this is that stretching to show  the faint tail with the limited data meant I also developed the streaks left by the stars. My knowledge of PS is not up to removing  broad faint streaks but leaving the tail.
Anyway, for better or worse:

Comet C/2017 T2 Panstarrs
Comet C/2017 T2 Panstarrs

C/2017 T2 (PANSTARRS)

Magnitude: 8.6

Phase: 36 °

Distance: 1.6765au

Solar distance: 1.6185au

Velocity: 33.1km/s

Estimated tail length: 0.04au

Messier 57 Ring Nebula in Lyra

Messier 57 is is just coming into a position for a decent look around 11 30 pm. IT is a colourful object and I thought it would give me a good target with which to practice my colour developing in PS/Lightroom. I have read so much about how to produce a LRGB image from the four stacked/calibrated luminance, red, blue and green images,  a lot seems contradicatory and some, when followed, gave me colour yes, but not as we know it. I am sure a fair chunk must be put down to me. Anyway, I now have a work flow which gives me colour, sometimes resembling what other people have obtained. Progess of sorts.

This images is based on 114s subs at gain 139, offset 21.
L 39, R 20, G 20, B 19
Calibrated  and stacked in DSS (flats, dark flats and darks)


NASA: M57, or the Ring Nebula, is a planetary nebula, the glowing remains of a sun-like star. The tiny white dot in the centre of the nebula is the star’s hot core, called a white dwarf. M57 is about 2,000 light-years away in the constellation Lyra, and is best observed during August. Discovered by the French astronomer Antoine Darquier de Pellepoix in 1779, the Ring Nebula has an apparent magnitude of 8.8 and can be spotted with moderately sized telescopes.

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, Celestron Focus Motor
Software: Ascom 6, Eqmod, Cartes du Ciel, AstroPhotography Tool, PHD2

Sunday 10 May 2020

Supernova in Virgo

Clouds rolled in , so only 45 mins worth of luminance (15 x 180s, gain 139, offset 21).    9th May 2020 22:25 UT

Supernova only discovered 2 days ago.


Thursday 7 May 2020

Galaxies in Cepheus

I now have around 5 hours of data in luminance for NGC2300 and friends. Not the best night still, since the moon was almost full, but the image is pretty good.
I will move on to RGB when I can.

Arp 114 in Cepheus





10th May 2020
I have now captured around 3 1/2 hours in luminance and 2 hours each of R, G and B. I have had to rethink how I process in LRGB; now, combine RGB straight away aftaer registration and stacking and keep checking colour balance.

Arp 114 in Cepheus

Tuesday 5 May 2020

NGC 2300 and NGC 2276 - Arp 114 in Cepheus

This is a pair of galaxies from Arp's catalogue. My intention is for this to be the start of a lot of data collection; the object is well placed and is always above the horizon from Locking. However, gibbous moon, clouds, ...sigh. Hence a lot of noise, light gradients  and nowhere near enough subs.

Wikipedia: Halton Christian "Chip" Arp (March 21, 1927 – December 28, 2013) was an American astronomer. He was known for his 1966 Atlas of Peculiar Galaxies, which (it was later theorized) catalogues many examples of interacting and merging galaxies, though Arp disputed the idea, claiming apparent associations were prime examples of ejections. Arp was also known as a critic of the Big Bang theory and for advocating a non-standard cosmology incorporating intrinsic redshift.

This image is based on 30 x 114s luminance filter, gain 139  , offset 21, -15 degrees C (darks, flats and dark flats).

Arp 114 in Cepheus


Astronomers don't think the two galaxies are interacting; 
"An odd couple lives some 100 million light years away. Here we find a spiral galaxy, NGC 2276 on the left, and its neighbor NGC 2300 on the right. There are quite a few intriguing questions concerning this pair. First of all NGC 2276 displays a perturbed spiral structure yet astronomers seem to agree that NGC 2300 is not the source of the angst. Instead, astronomers have learned that there is an abundance of gas (not shown in this picture) surrounding these galaxies. It could be that NGC 2276's motion through the gas affects its morphology." http://www.jwinman.com/starcharts/NGC%202300%20chart.htm

There are other galaxies visible, including IC 455