Image by Dale Liebenberg

NGC 7293 Helix Nebula in Aquarius

About 20x20min Each Ha, OIII, & SII

Modified Hubble palette

Image scale 0.47 arsec/pixel

Image size +- 28x18 arcmin

Captured with MaximDL

Processed with PS CS4

Equipment:

Scope: Celestron EdgeHD 14"

Mount: ASA DDM60

Camera: FLI Microline 11002, Astrodon filters

Guiding: MMOAG with Loadstar camera

Focuser: FLI Atlas

Software:

TheSkyX, ACP Planner, ACP, ACP Scheduler, FMax, MaximDL, Photoshop CS4

Location:

Port Elizabeth, South Africa

Helix Nebula from ESO using a different palette than NASA.

Soap Bubble in Space. I have wanted to image this planetary nebula since it was first discovered in 2008. The field of view is only 12 arc minutes wide, no cropping. It’s a total of 44.5 hours of data that I captured from 23 nights of imaging from August 11-Oct. 22, 2020. Captured with my Ceravolo300mm at f/9 with an SBIG Aluma 694 CCD camera.

The true colours of the nebulosity in space are due to the combinations of gas emissions coming from them and everything along our line of sight like galactic dust. This Soap Bubble nebula is the blown off atmosphere from a single dying star. It is emitting hydrogen-alpha which is red and oxygen which is blue-green. The combination of these light colours is yellow/gold as seen in the outer rim of the bubble. I used three narrowband filters, Hydrogen-alpha, oxygen and hydrogen-beta. The blue hydrogen-beta makes the hydrogen-alpha gas appear pink but only when there is not much galactic dust in the way.

Technical details:

telescope: Ceravolo300 at f/9

Camera: SBIG Aluma 694

Filters: Astrodon RGB, Ha, Hb, OIII

Total 44.5 hours

Location: Personal observatory, BC, Canada

It's not much to look at, but this planetary nebula is pretty much amazing. To understand why, first one must understand why the oxygen content is important. If you check out the Wiki article on metallicity you find that the ages of stars are determined like this. So, essentially, for this planetary nebula, the less oxygen there is, the older it is presumed to be. The HST Proposal even suggested that perhaps this was a Population III PN, but alas, that is not the case. Still, it had astronomers going for a while because it is so oxygen-poor. It's the most oxygen-poor PN yet known and it's way out there in our galactic halo.

Other interesting bits include the fact that the central star is a close binary with an orbital period of only a few hours and the possibility of this sucker one day becoming a Type Ia supernova. How cool would that be? You never know when it might happen. Ok, probably not while I'm still alive, but whatever, I'm not giving up hope. You can do it, TS 01!

All of this and more I got from this paper, "The chemical composition of TS 01, the most oxygen-deficient planetary nebula. AGB nucleosynthesis in a metal-poor binary star" by G. Stasinska, et al.

In 2003, HST was instructed to look at this object for more than four hours to bring you this image, meager as it seems.

Red: HST_9466_01_ACS_HRC_F658N_sci

Green: Pseudo

Blue: HST_9466_01_ACS_HRC_F344N_sci

North is up.

The necklace nebula is weird. Sure, it glows in all the usual colors, but the little red bits are arranged perfectly in a circle around the central stars (visible as a single star) and then there are the two other red bits at considerable distance from the rest of the nebula at the upper left and lower right. I brightened those distant ones a little to make them easier to see. To understand these baffling features, I recommend reading this article because the authors definitely know more than I do.

Red: hst_12675_01_wfc3_uvis_f814w_sci + hst_12675_01_wfc3_uvis_f658n_sci

Green: hst_12675_01_wfc3_uvis_f555w_sci + hst_12675_01_wfc3_uvis_f656n_sci

Blue: hst_12675_01_wfc3_uvis_f438w_sci + hst_12675_01_wfc3_uvis_f502n_sci

North is up.

One of the three planetary nebulas discovered by M. L. Humason during his time at the Mount Wilson Observatory. Any aspiring astronomer should read that short Wiki article at the link.

Here, the swirling, vaguely symmetrical nebula is seen in detail with two narrowband filters (F658N & F656N). The broad, blueish dots arranged in the X shape are simply diffuse diffraction spikes and are not part of the nebula itself. The central star is just discernible.

The image has been enlarged 200% from its original size.

These data were collected for Proposal 6347, A Search for Jets in Planetary Nebulae

Red: hst_06347_08_wfpc2_f658n_pc_drz

Green: Pseudo

Blue: hst_06347_09_wfpc2_f656n_pc_drz

North is up.

NGC 6751, also known as the Glowing Eye Nebula or Dandelion Puffball Nebula, is a planetary nebula in the constellation Aquila. The nebula is estimated to be around 0.8 light-years in diameter. The star at the centre of the nebula has a surface temperature of approximately 140,000 K. It has been calculated to be roughly 6,500 light-years away from Earth. It was formed when a star collapsed and threw off its outer layer of gas several thousand years ago.

I sketched this using a mixture of oil pastels and chalk pastels on black paper back in 2014 when my surname was still Spicer, hence the sketch is initialled "MLS" It was made into a birthday card for my husband.

Edited Spitzer Space Telescope image of the Helix Nebula.

Original caption: A newly expanded image of the Helix nebula lends a festive touch to the fourth anniversary of the launch of NASA's Spitzer Space Telescope. This spectacular object, a dying star unraveling into space, is a favorite of amateur and professional astronomers alike. Spitzer has mapped the expansive outer structure of the six-light-year-wide nebula, and probed the inner region around the central dead star to reveal what appears to be a planetary system that survived the star's chaotic death throes.

M76 is a small planetary nebula in the constellation of Perseus. It is also known as the Little Dumbbell Nebula because of its superficial similarity to another large planetary nebula M27.

Takahashi Sky 90 at f/4.5

SBIG STL-4020M (self-guided)

Takahashi EM-200

Hutech LPS filter

RGB: 40 minutes each channel (5 minute exposures)

Processed with Maxim/DL and Photoshop CS3

Noel Carboni's Astronomy Tools

best large.

I have to say that as far as Hubble exposures of planetary nebulas go, IC 1454 is not the most visually rewarding. I've searched for some amateur astrophotography pictures and it seems a bit better suited for that. It's big and diffuse and pretty blurry up close. It also seems somewhat faint.

Anyway, the data had a fairly low s/n ratio but I figured I'd try it anyway. I used to hate the median filter but I'm beginning to see some merits to it in certain situations. It definitely helped smooth out the noise without destroying details, which I masked off, retaining the integrity of the little stars and that smudge which I believe is a background galaxy.

There are some neat planetary nebulas which are simply perfect round circles or bubbles but they are usually too big to fit on a single WFPC2 exposure. By dumb luck it seems this one wasn't quite aimed correctly on the first attempt which resulted in me being able to create a slightly more complete picture of it.

Red: hst_07501_10_wfpc2_f658n_pc_sci + hst_07501_10_wfpc2_f658n_wf_sci + hst_07501_60_wfpc2_f658n_pc_sci + hst_07501_60_wfpc2_f658n_wf_sci

Green:hst_07501_10_wfpc2_f555w_pc_sci + hst_07501_10_wfpc2_f555w_pc_sci + hst_07501_60_wfpc2_f555w_pc_sci + hst_07501_60_wfpc2_f555w_wf_sci

Blue: hst_07501_10_wfpc2_f502n_pc_sci + hst_07501_10_wfpc2_f502n_wf_sci + hst_07501_60_wfpc2_f502n_pc_sci + hst_07501_60_wfpc2_f502n_wf_sci

North is NOT up, it's 36.5° degrees counter-clockwise from up.

This nebula is named after Jacoby and Fulton who, along with others, were rewarded with the discovery of this tiny planetary nebula buried in the haze of stars known as the loose globular cluster Palomar 6. Finding the few existing planetary nebulas in globular clusters is something like the astronomer's ultimate game of Where's Waldo. Congratulations, guys. Anyway, this curious blob (or perhaps the name itself: "What's a JaFu??") managed to catch my attention in the archive so I went ahead and processed it.

Obviously, wideband filters barely reveal the little feller at all. The nebula is mainly visible in the F656N (H-alpha) & F502N (OIII) data. I toned the wideband data down quite a bit to tame the various bright stars.

Red: hst_11308_01_wfpc2_f814w_wf_sci + hst_11308_01_wfpc2_f656n_wf_sci

Green: hst_11308_01_wfpc2_f555w_wf_sci

Blue: ACS/WFC F502N (jb1w02010_drz)

North is up.

It looks like someone plucked a few of the petals off, but I can see why this was named the water lily. This is another in the preplanetary (or protoplanetary) nebula category.

Slight rant warning:

I call them preplanetary because protoplanetary is too easily confused with protoplanetary disks which have nothing to do with protoplanetary nebulas. I'll be happy on the day astronomers finally do away with the "planetary" part of the name entirely. I have to have hope that someday that will happen for the sake of reason and scientists like reason. ...Right?

I probably should have removed the diffraction spikes since the two exposures make them kind of awkward. I might do that later.

Red: hst_08210_01_wfpc2_f814w_pc_sci

Green: pseudo

Blue: hst_06565_03_wfpc2_f606w_pc_sci

North is up.

Small but bright and pretty, IC 4663 is even more interesting than it seems at first glance. A quick search instantly directs one to various papers pointing out that the central star for this planetary nebula is, in fact, a Wolf-Rayet star.

Note that data is discreetly missing from the corners.

Red: hst_08773_12_wfpc2_f658n_pc_sci

Green: hst_07501_65_wfpc2_f555w_pc_sci

Blue: hst_08773_12_wfpc2_f502n_pc_sci

North is up.

Ring Nebula in Lyra. This planetary nebula is quite small (~3 arcmin) but even more so when viewed at a wide angle. The two bright stars are Sulafat and Sheliak in Lyra. Best viewed in original size.

Imaging scope: Astro-Tech 65 Quadruplet (LRGB)

Imaging Camera: ST8300M (capture with Equinox Image)

Filters: Baader filters in FW5-8300 filter wheel

Guide scope: Astro-Tech 106mm Triplet

Guide camera: Starfish Fishcamp (guided with PHD)

Mount: Atlas EQ-G

Calibrated in Equinox Image and processed in PixInsight.

L - 8min 8x1min (1x1)

RGB - 4min each 4x1min (1x1)

Small but bright and pretty, NGC 6884 wasknown to be a bright, round disk until Hubble took a look at it, revealing complex details. It's a shame that many planetary nebulas are so hard to see. It would appear even more bright if it were not for our Milky Way's interloping dust.

Red: hst_06119_41_wfpc2_f814w_pc_sci+hst_08390_08_wfpc2_f658n_pc_sci

Green: hst_08390_08_wfpc2_f555w_pc_sci

Blue: hst_08390_08_wfpc2_f502n_pc_sci

North is up.

A fairly obscure planetary nebula that's actually rather pretty. There seems to be a ring of knots around the center. I'm not sure the central star is visible in this image. There is one that might be it but it's off center and it wouldn't be the first time a central star failed to appear in some f656n data.

This is a single channel of data with some artificial color applied. Corners are discreetly missing data.

All channels: hst_08345_33_wfpc2_f656n_pc_sci

North is up.

M27 / NGC 6853 - Dumbbell Nebula

The Dumbbell Nebula is located in the constellation of Vulpecula and at a distance of approximately 1360 light years from earth.

The nebula is classed as a Planetary Nebula, there is a central star to this Nebula, which is probably as a result of a star that exploded and shed it's outer layer resulting in the formation of the nebula itself.

This is my first image with my new Astro Tech 8 Inch Ritchey–Chrétien, the image details are as follows:

Canon 500D Modified (Imaging Camera)

Astro Tech 8" Ritchey–Chrétien with AT2FF Field Flattener

Orion Star Shoot Autoguider (Guide Camera)

Celestron C80ED Apo Refractor (Guide Scope)

27x 5 Min Exposures at ISO 800

41 Dark Frames

43 Flat Frames

Images Acquired with BackyardEOS

Images Stacked and Pre-Processed with Nebulosity 2

Images Post Processed with Photoshop CS5

NGC6741 is quite small but also quite bright and various details are easily discerned. It has a somewhat rectangular or parallelogram shape from our vantage point and the skinny, somewhat linear structure around the center has a curved shape implying that it may encircle the star all the way around though we can only see the side facing us.

Kaler mentions that the central star is unseen but it is clearly visible here and I do see it in the Hubble image he provided with his description. It is quite easily noticed in the f555w data even without sharpening. It is indeed invisible in the other two sets of data, f658n and f502n.

I don't know who called it the Phantom Streak or why it is called that. Most small nebulas like this don't receive common names. It's a cool name though so we may as well go with it.

Red: hst_08773_04_wfpc2_f658n_pc_sci

Green: hst_07501_04_wfpc2_f555w_pc_sci

Blue: hst_08773_04_wfpc2_f502n_pc_sci

North is up.

Lots of details in this one even though it's small. There is also an extremely faint arc to the left of M 2-40 but it's so faint it is only slightly above the noise.

This is a single channel of data that has been subjectively colorized.

Data is missing at the corners because I like to present things north up instead of rotating the picture to fit in a box.

All channels: hst_08345_23_wfpc2_f656n_pc_sci

North is up.

If you look at enough planetary nebulas you know they like to be random and avoid fitting comfortably into categories. One feature, however, seems rather common--a bright central core with sharply defined edges surrounded by another layer which is roughly half as bright and less sharply defined. Interesting, reticulated patterns can be seen in both layers and they are usually roughly elliptical in shape if not perfectly circular. IC 2448 is a typical example. It seems to lack FLIERs, however. (I only recently realized FLIERs is an acronym. Fliers as a rather simple noun seems to fit them even without the complexity of an acronym.)

Corners are discreetly missing data.

Red: hst_11122_03_wfpc2_f656n_pc_sci + hst_06119_49_wfpc2_f814w_pc_sci

Green: hst_06119_49_wfpc2_f555w_pc_sci

Blue: hst_08390_14_wfpc2_f502n_pc_sci

North is up.

NGC 6565 looks to me like a miniature Ring Nebula. I'm rather fond of these nebulas with rather rainbow-like gradients from blue in the center to red at the perimeter.

I made an effort to reduce the size of the stars which would otherwise be bright green due to the green channel being f555w.

Red: hst_08773_01_wfpc2_f658n_pc_sci

Green: hst_07501_01_wfpc2_f555w_pc_sci

Blue: hst_08773_01_wfpc2_f502n_pc_sci

North is NOT up, it's 45° clockwise from up

Again, I used data from the WF chips in combination with the PC chip data in order to create a slightly more complete view of a nebula. As usual, I’d still like if it were not cut off on the side, but you learn to take what you can get. :)

Red: hst_07501_09_wfpc2_f658n_pc_sci + hst_07501_09_wfpc2_f658n_wf_sci

Green: hst_07501_09_wfpc2_f555w_pc_sci + hst_07501_09_wfpc2_f555w_wf_sci

Blue: hst_08773_08_wfpc2_f502n_pc_sci + hst_07501_09_wfpc2_f502n_pc_sci + hst_08773_08_wfpc2_f502n_wf_sci

North is NOT up, it's 8.7° counter-clockwise from up

Well, this looks like a preplanetary nebula to me, but we all know looks can deceive. I do know that there is no strict line between a preplanetary and a planetary nebula so it is understandable that I wonder why this one is is not classified as preplanetary. Anyway, it's also one of those weird planetaries with a WC Wolf-Rayet central star. It wouldn't be the first time I've been thrown off by one of those. Strange. It might not even be a planetary nebula but rather more precisely an ejecta shell. Oh well, another day, another nebula.

Red: HST_9463_80_ACS_HRC_F606W_sci

Green: Pseudo

Blue: HST_9463_80_ACS_HRC_F435W_sci

North is up.

I thought this was a faint galaxy when I first saw it in the archive because it looked like it had spiral arms. It's not a very visually appealing nebula but the collection does not discriminate! Apparently there's more to this one than Hubble's exposures were able to capture. The PC chip where most planetary nebula are imaged seems to unfortunately not be very good at picking up faint details. I don't understand this.

Red: hst_06119_53_wfpc2_f814w_pc_sci

Green: Pseudo

Blue: hst_06119_53_wfpc2_f555w_pc_sci

Information on this nebula and how it can be mistaken for a double star is here. I reduced the glare from the star it gets confused with. I'd prefer the focus to be on the nebula itself rather than the relatively bright nearby star.

Red: hst_08773_09_wfpc2_f658n_pc_sci

Green: hst_07501_11_wfpc2_f555w_pc_sci

Blue: hst_08773_09_wfpc2_f502n_pc_sci

North is NOT up

Instead of using pseudogreen like I usually do when presented with only two channels to work with I put the f555w data into both the green and blue channels and adjusted the blue one to look similar to NGC 2867 since that one actually does have three wideband channels and they are somewhat similar looking objects. It's still pseudo-something, I'm just not sure what.

Red: hst_06119_13_wfpc2_f814w_pc_sci

Green: hst_06119_13_wfpc2_f555w_pc_sci

Blue: hst_06119_13_wfpc2_f555w_pc_sci

Another teeny planetary nebula. Here, a slightly perturbed figure-eight and some faint concentric rings are visible. What are these shapes, really? For an idea, I would take a look at a closer planetary nebula which is a bit easier to see. The Etched Hourglass seems related.

Triangles of data are missing from the lower left and right corners.

Red: hst_08345_37_wfpc2_f658n_pc_sci

Green: Pseudo

Blue: hst_08345_37_wfpc2_f656n_pc_sci

North is up.

Hen 1-1 is small, faint, and kind of fuzzy looking. Still, there are some details to discern, such as the two small structures separated and flanking the nebula to the lower left and upper right. I wouldn't try to read too much into the other patchy bits of dim noise around the nebula. Some of those slightly brighter spots are the result of imperfect cosmic ray removal. Parallel, diagonal linear structures are just readout noise.

Single channel of data subjectively colorized. Data is unavailable for three flat triangular shapes in the corners.

All channels: hst_06347_34_wfpc2_f656n_pc_sci

North is up.

Vy 2-3 is pretty round but not perfectly round. The Lemon Slice remains the reigning champion of roundness. "Vy" is a new name to me so I had to look it up. This seems to be another case of, "Wait, this isn't just a star. The emission lines are weird." So the Vy is for Vyssotsky, who discovered it while surveying stars.

All channels: hst_08345_16_wfpc2_f656n_pc_sci

North is up.

Robert Jonckheere was searching for double stars. Some of them turned out to be planetary nebulas, like J 900. They are both in his double-star catalog so I wondered if he ever realized his mistake. I looked it up and he did go back to them later with a larger instrument and discovered they were actually nebulas.

As usual, data is absent from the corners so I could maintain the north-up orientation of the object. The color is subjectively added.

All channels: hst_06347_13_wfpc2_f656n_pc_sci

North is up.

One of the rare planetary nebulas found within a globular cluster. Wikipedia informs me that there are only four others discovered so far. Here is a great article which includes a human eye color approximation view, because people are always very interested in that. Personally, I don't see what is interesting about that, because a lot of space objects are just pale green without any color variation to our eyes. I'm happy we have instruments to aid our vision of the cosmos.

I went with the filters which the nebula shined the most brightly in so that light from the cluster wouldn't overpower the light from the nebula. Since planetary nebulas tend to glow rather brightly through a couple of narrowband filters, it's possible to see the nebula much more clearly using them.

Red: hst_06751_03_wfpc2_f656n_pc_sci

Green: hst_06751_01_wfpc2_f502n_pc_sci

Blue: hst_06751_01_wfpc2_f336w_pc_sci

North is up.

Note the H in H 2-1 is different from Hen which are from Henize's catalogs. Henize cataloged this one as Hen 2-194. The H in this case refers to Haro. There's a paper about its discovery here but it's in Spanish. Anyway, that confused me a bit when I was looking at the various designations for this one so I thought I'd mention it.

Red: hst_08345_25_wfpc2_f658n_pc_sci

Green: Pseudo

Blue: hst_08345_25_wfpc2_f656n_pc_sci

North is up.

This one is tiny but surprisingly bright. There were broad diffraction spikes I removed since it is a small, bright source.

This is a single channel of data subjectively colorized. Some triangles of data are missing from the corners.

You have to the two 200 second exposures rather than the combined data because the 400 second exposures used to create the combined data are completely saturated/blown out in the middle, obscuring the subtle details such as the central star and slightly dimmer areas.

All channels: hst_06353_06_wfpc2_f656n_pc_03_drz + hst_06353_06_wfpc2_f656n_pc_04_drz

North is up.

Sorry it's cut off on the lower edge. That's just how things are. Some interesting tidbits are written about it in its Wikipedia article. Apparently it's approaching our position. Or perhaps we are approaching it. Either way, the distance between us and NGC 3195 is lessening over time.

Red: hst_06119_16_wfpc2_f814w_pc_sci + hst_06119_16_wfpc2_f814w_wf_sci

Green: Pseudo

Blue: hst_06119_16_wfpc2_f555w_pc_sci + hst_06119_16_wfpc2_f555w_wf_sci

North is NOT up

A nice, small, bright bipolar planetary nebula. It closely resembles Minkowski 2-9 in its structure, which is interesting. Planetary nebulae are still like snowflakes though, they are all very unique (for the most part). This catalogue is small, containing only three nebulae, the most famous being Fleming 1, which is one of my favourite planetary nebulae. There is data available for Fg 2 in the ESO archive as well which I plan on checking out.

These data were collected for proposal 8345: Multipolar Bubbles and Jets in Very Low Excitation Planetary Nebulae

This image is enlarged by 150%

Red: hst_08345_13_wfpc2_f658n_wf

Green: pseudo

Blue: hst_08345_13_wfpc2_f656n_pc

Edited Hubble Space Telescope image of the planetary nebula (which doesn't look very round here) NGC 5307. Color/processing variant.

Original caption: This Picture of the Week from the NASA/ESA Hubble Space Telescope shows NGC 5307, a planetary nebula which lies about 10000 light years from Earth. It can be seen in the constellation Centaurus (The Centaur), which can be seen primarily in the southern hemisphere. A planetary nebula is the final stage of a Sun-like star. As such, planetary nebulae allow us a glimpse into the future of our own Solar System. A star like our Sun will, at the end of its life, transform into a red giant. Stars are sustained by the nuclear fusion that occurs in their core, which creates energy. The nuclear fusion processes constantly try to rip the star apart. Only the gravity of the star prevents this from happening.

At the end of the red giant phase of a star, these forces become unbalanced. Without enough energy created by fusion, the core of the star collapses in on itself, while the surface layers are ejected outward. After that, all that remains of the star is what we see here: glowing outer layers surrounding a white dwarf star, the remnants of the red giant star’s core.

This isn’t the end of this star’s evolution though — those outer layers are still moving and cooling. In just a few thousand years they will have dissipated, and all that will be left to see is the dimly glowing white dwarf.

Nice, faint halo around this one. Halos are actually very common features for planetary nebulas but they often aren't included because they are so faint. In Hubble's case, a lot of the time the halo is just too big to be included in the frame.

This is a single channel of data which I colorized.

All channels: hst_08345_10_wfpc2_f656n_pc_sci

North is up.

This tiny nebula only had one channel of data so I colorized it to a sort of blue-green nebula color.

When I finally get done finding all these in the archive you'll see why I like processing the tiny ones too. I am making a big collage of them all and it looks really cool with the itty bitty ones filling the space between the larger ones.

Original size is zoomed 200% from original pixels.

All channels: hst_08345_01_wfpc2_f656n_pc_sci

North is up.

Owl nebula (Messier 97) shot in LRGB. 6*10min per channel at 2x2 binning.

At the end of this season the first night of the summer without astronomical darkness was still barely dark enough to get 4 hours of exposures of this wonderful (but small) nebula.

Gear: HEQ5, C8, .63x reducer, OAG+Lodestar, EFW2, Baader LRGB filters, SXVR-H18

SW: MaxImDL, AstroTortilla, PixInsight

Just another little planetary nebula. It looks like a very tiny spiral galaxy. You could say it is an actual spiral nebula, what spiral galaxies used to be called.

This view is zoomed 150% from original pixels.

Red: hst_08345_05_wfpc2_f658n_pc_sci

Green: Pseudo

Blue: hst_08345_05_wfpc2_f656n_pc_sci

North is up.

Another day, another tiny planetary nebula. If you ever wanted to know what PN M 1-61 looks like, here is your chance. There seems to be a whole set of these tiny ones in the archive for a reason. Maybe I should find out why, but, then, you know, I'd have to read instead of process pictures. Decisions, decisions.

Red: hst_08307_03_wfpc2_f658n_pc_sci

Green: hst_08307_03_wfpc2_f656n_pc_sci

Blue: hst_08307_03_wfpc2_f502n_pc_sci

North is up.

Edited Chandra Space Telescope image of the supernova remnant Cassiopeia A, with colors representing the various metals (to an astronomer, if it's not hydrogen or helium, it's a metal) in the nebula formed from the explosion. Silicon is red, sulfur is yellow, calcium is green, and iron is purple. (Blue is the blast wave.) Color/processing variant.

Original caption: Where do most of the elements essential for life on Earth come from? The answer: inside the furnaces of stars and the explosions that mark the end of some stars' lives.

Astronomers have long studied exploded stars and their remains — known as "supernova remnants" — to better understand exactly how stars produce and then disseminate many of the elements observed on Earth, and in the cosmos at large.

Due to its unique evolutionary status, Cassiopeia A (Cas A) is one of the most intensely studied of these supernova remnants. A new image from NASA's Chandra X-ray Observatory shows the location of different elements in the remains of the explosion: silicon (red), sulfur (yellow), calcium (green) and iron (purple). Each of these elements produces X-rays within narrow energy ranges, allowing maps of their location to be created. The blast wave from the explosion is seen as the blue outer ring.

X-ray telescopes such as Chandra are important to study supernova remnants and the elements they produce because these events generate extremely high temperatures — millions of degrees — even thousands of years after the explosion. This means that many supernova remnants, including Cas A, glow most strongly at X-ray wavelengths that are undetectable with other types of telescopes.

Chandra's sharp X-ray vision allows astronomers to gather detailed information about the elements that objects like Cas A produce. For example, they are not only able to identify many of the elements that are present, but how much of each are being expelled into interstellar space.

The Chandra data indicate that the supernova that produced Cas A has churned out prodigious amounts of key cosmic ingredients. Cas A has dispersed about 10,000 Earth masses worth of sulfur alone, and about 20,000 Earth masses of silicon. The iron in Cas A has the mass of about 70,000 times that of the Earth, and astronomers detect a whopping one million Earth masses worth of oxygen being ejected into space from Cas A, equivalent to about three times the mass of the Sun. (Even though oxygen is the most abundant element in Cas A, its X-ray emission is spread across a wide range of energies and cannot be isolated in this image, unlike with the other elements that are shown.)

Astronomers have found other elements in Cas A in addition to the ones shown in this new Chandra image. Carbon, nitrogen, phosphorus and hydrogen have also been detected using various telescopes that observe different parts of the electromagnetic spectrum. Combined with the detection of oxygen, this means all of the elements needed to make DNA, the molecule that carries genetic information, are found in Cas A.

Oxygen is the most abundant element in the human body (about 65% by mass), calcium helps form and maintain healthy bones and teeth, and iron is a vital part of red blood cells that carry oxygen through the body. All of the oxygen in the Solar System comes from exploding massive stars. About half of the calcium and about 40% of the iron also come from these explosions, with the balance of these elements being supplied by explosions of smaller mass, white dwarf stars.

While the exact date is not confirmed (PDF), many experts think that the stellar explosion that created Cas A occurred around the year 1680 in Earth's timeframe. Astronomers estimate that the doomed star was about five times the mass of the Sun just before it exploded. The star is estimated to have started its life with a mass about 16 times that of the Sun, and lost roughly two-thirds of this mass in a vigorous wind blowing off the star several hundred thousand years before the explosion.

Earlier in its lifetime, the star began fusing hydrogen and helium in its core into heavier elements through the process known as "nucleosynthesis." The energy made by the fusion of heavier and heavier elements balanced the star against the force of gravity. These reactions continued until they formed iron in the core of the star. At this point, further nucleosynthesis would consume rather than produce energy, so gravity then caused the star to implode and form a dense stellar core known as a neutron star.

The exact means by which a massive explosion is produced after the implosion is complicated, and a subject of intense study, but eventually the infalling material outside the neutron star was transformed by further nuclear reactions as it was expelled outward by the supernova explosion.

Chandra has repeatedly observed Cas A since the telescope was launched into space in 1999. The different datasets have revealed new information about the neutron star in Cas A, the details of the explosion, and specifics of how the debris is ejected into space.

NASA's Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program for NASA's Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, controls Chandra's science and flight operations.

This is my last photograph captured from my observatory.

I have always been impressed by the photography made by the Hubble Space Telescope, so I wanted to pay homage to it simply using my modest equipment

So I used my SW Esprit 150 f7 telescope and my QHY268M CMOS with the Ha, SII and OIII filters accumulating 10h in 5-minute subshots.

Now I want to capture more signal in Halpha to bring out the faint features around the eye.

Hope you like it!

Edited European Southern Observatory image of the planetary nebula Abell 33.

Original caption: Astronomers using ESO’s Very Large Telescope in Chile have captured this eye-catching image of planetary nebula Abell 33. Created when an aging star blew off its outer layers, this beautiful blue bubble is, by chance, aligned with a foreground star, and bears an uncanny resemblance to a diamond engagement ring. This cosmic gem is unusually symmetric, appearing to be almost perfectly circular on the sky.

Image of a nebula taken using a NASA telescope -

Original from NASA. Digitally enhanced by rawpixel.

Taken from New Mexico Skies Observatory using an SBIG STL-6303 camera and 51-cm RCOS telescope on a Software Bisque PME 1 Mount

LRGB

LINK

Other images from this series:

1. www.flickr.com/photos/jbrimacombe/51912817758/

2. www.flickr.com/photos/jbrimacombe/51913339650/

3. www.flickr.com/photos/jbrimacombe/51912722131/

4. www.flickr.com/photos/jbrimacombe/51912817498/

5. www.flickr.com/photos/jbrimacombe/51911758022/

6. www.flickr.com/photos/jbrimacombe/51911757837/

NOTE

1. The marked blue star in the geometric centre is the probable source of the nebula.

2. The Soap Bubble Nebula, or PN G75.5+1.7, is a planetary nebula in the constellation Cygnus, near the Crescent Nebula (NGC 6888). It was discovered by amateur astronomer Dave Jurasevich using an Astro-Physics 160 mm refractor telescope with which he imaged the nebula on June 19, 2007 and on July 6, 2008. The nebula was later independently noted and reported to the International Astronomical Union by Keith B. Quattrocchi and Mel Helm who imaged PN G75.5+1.7 on July 17, 2008. The nebula measures 260″ in angular diameter with a central star that has a J band magnitude of 19.45.

Edited Chandra Space Telescope image of the supernova remnant Cassiopeia A, with colors representing the various metals (to an astronomer, if it's not hydrogen or helium, it's a metal) in the nebula formed from the explosion. Silicon is red, sulfur is yellow, calcium is green, and iron is purple. (Blue is the blast wave.) Color/processing variant.

Original caption: Where do most of the elements essential for life on Earth come from? The answer: inside the furnaces of stars and the explosions that mark the end of some stars' lives.

Astronomers have long studied exploded stars and their remains — known as "supernova remnants" — to better understand exactly how stars produce and then disseminate many of the elements observed on Earth, and in the cosmos at large.

Due to its unique evolutionary status, Cassiopeia A (Cas A) is one of the most intensely studied of these supernova remnants. A new image from NASA's Chandra X-ray Observatory shows the location of different elements in the remains of the explosion: silicon (red), sulfur (yellow), calcium (green) and iron (purple). Each of these elements produces X-rays within narrow energy ranges, allowing maps of their location to be created. The blast wave from the explosion is seen as the blue outer ring.

X-ray telescopes such as Chandra are important to study supernova remnants and the elements they produce because these events generate extremely high temperatures — millions of degrees — even thousands of years after the explosion. This means that many supernova remnants, including Cas A, glow most strongly at X-ray wavelengths that are undetectable with other types of telescopes.

Chandra's sharp X-ray vision allows astronomers to gather detailed information about the elements that objects like Cas A produce. For example, they are not only able to identify many of the elements that are present, but how much of each are being expelled into interstellar space.

The Chandra data indicate that the supernova that produced Cas A has churned out prodigious amounts of key cosmic ingredients. Cas A has dispersed about 10,000 Earth masses worth of sulfur alone, and about 20,000 Earth masses of silicon. The iron in Cas A has the mass of about 70,000 times that of the Earth, and astronomers detect a whopping one million Earth masses worth of oxygen being ejected into space from Cas A, equivalent to about three times the mass of the Sun. (Even though oxygen is the most abundant element in Cas A, its X-ray emission is spread across a wide range of energies and cannot be isolated in this image, unlike with the other elements that are shown.)

Astronomers have found other elements in Cas A in addition to the ones shown in this new Chandra image. Carbon, nitrogen, phosphorus and hydrogen have also been detected using various telescopes that observe different parts of the electromagnetic spectrum. Combined with the detection of oxygen, this means all of the elements needed to make DNA, the molecule that carries genetic information, are found in Cas A.

Oxygen is the most abundant element in the human body (about 65% by mass), calcium helps form and maintain healthy bones and teeth, and iron is a vital part of red blood cells that carry oxygen through the body. All of the oxygen in the Solar System comes from exploding massive stars. About half of the calcium and about 40% of the iron also come from these explosions, with the balance of these elements being supplied by explosions of smaller mass, white dwarf stars.

While the exact date is not confirmed (PDF), many experts think that the stellar explosion that created Cas A occurred around the year 1680 in Earth's timeframe. Astronomers estimate that the doomed star was about five times the mass of the Sun just before it exploded. The star is estimated to have started its life with a mass about 16 times that of the Sun, and lost roughly two-thirds of this mass in a vigorous wind blowing off the star several hundred thousand years before the explosion.

Earlier in its lifetime, the star began fusing hydrogen and helium in its core into heavier elements through the process known as "nucleosynthesis." The energy made by the fusion of heavier and heavier elements balanced the star against the force of gravity. These reactions continued until they formed iron in the core of the star. At this point, further nucleosynthesis would consume rather than produce energy, so gravity then caused the star to implode and form a dense stellar core known as a neutron star.

The exact means by which a massive explosion is produced after the implosion is complicated, and a subject of intense study, but eventually the infalling material outside the neutron star was transformed by further nuclear reactions as it was expelled outward by the supernova explosion.

Chandra has repeatedly observed Cas A since the telescope was launched into space in 1999. The different datasets have revealed new information about the neutron star in Cas A, the details of the explosion, and specifics of how the debris is ejected into space.

NASA's Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program for NASA's Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, controls Chandra's science and flight operations.

Edited European Southern Observatory image of the planetary nebula NGC 6781. Color/processing variant.

Original caption: Stars such as our Sun do not contain enough mass to finish their lives in the glorious explosions known as supernovae. However, they are still able to salute their imminent demise into dense, Earth-sized embers called white dwarfs by first expelling colourful shells of gas known as planetary nebulae. This misnomer comes from the similarity in appearance of these spherical mass expulsions to giant planets when seen through small telescopes. NGC 6781 is a nice representative of these cosmic bubbles. The planetary nebula lies a few thousand light-years away towards the constellation of Aquila (the Eagle) and is approximately two light-years across. Within NGC 6781, shells of gas blown off from the faint, but very hot, central star’s surface expand out into space. These shells shine under the harsh ultraviolet radiation from the progenitor star in intricate and beautiful patterns. The central star will steadily cool down and darken, eventually disappearing from view into cosmic oblivion. This image was captured with the ESO Faint Object Spectrograph and Camera (EFOSC2) through three wide band filters (B, V, R) and two narrow-band ones (H-alpha, OIII). EFOSC2 is attached to the 3.6-metre telescope at ESO’s La Silla Observatory in Chile. EFOSC2 has a field of view of 4.1 x 4.1 arcminutes.