" Multi coloured 'Sun dog' to the left of the Sun over Oulton Broad, observed whilst the team was enjoying a pint or two at the Wherry Hotel" - Joel Cairo CEO of the JPO the UK's most easterly Astronomical Observatory".
" Multi coloured 'Sun dog' to the left of the Sun over Oulton Broad, observed whilst the team was enjoying a pint or two at the Wherry Hotel" - Joel Cairo CEO of the JPO the UK's most easterly Astronomical Observatory".
"As many readers will know Kurt is both old and unwell and consequently no one was surprised when he inadvertently erased 400 images from our sponsors astro-imaging Flickr account. As an act of contrition, he has set up a new Flickr account for George Roberts and is uploading images to repopulate it. He is taking the opportunity to reprocess some of the lost and older images with state of the art software and to reformat and modernise the presentation". - Joel Cairo CEO of the Jodrell Plank Observatory.
" The Helix Planetary Nebula being relatively nearby and colourful is often imaged and presented on the Internet. Often the complexity of this nebula is overlooked in the images of amateur astronomers. Pip has used his processing skills to bring out details captured by the research grade robotic telescope". - Kurt Thrust current Director of the Jodrell Plank Observatory.
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| Curious Cometary Knots in the Helix Nebula Image Credit: NASA, ESA, CSA, STScI, JWST; Processing: A. Pagan (STScI) |
Commentary by visiting Astrophysicist Professor G.P.T Chat
The top image of the Helix Planetary Nebula (NGC 7293) is a four-panel comparison of differently enhanced narrowband representations. The images emphasize the nebula’s extraordinary ionization structure, concentric shell morphology, filamentary outer gas, and the contrast between its highly ionized interior and lower-ionization envelope. The colour assignments in the figure are processing choices rather than direct visible-light colours; they are intended to make emission from particular ionic species diagnostically apparent.
The Helix Nebula is a nearby planetary nebula, the expanding ionized circumstellar envelope produced during the late evolutionary stages of a low- to intermediate-mass star. At its centre lies the exposed stellar remnant—the hot central star, now evolving toward the white-dwarf stage. Intense ultraviolet radiation from this compact, extremely hot source ionizes the surrounding gas, producing the characteristic emission-line spectrum of the nebula. Despite its name, a planetary nebula has no physical connection to planets; the historical terminology arose from the roughly disk-like appearance of some early examples.
The most immediately striking feature in the uploaded image is the large, approximately annular main shell. It appears as a luminous red-orange outer region surrounding a much more intensely blue-green interior. This morphology reflects a strongly stratified ionization structure rather than a simple shell of uniform composition. The central cavity is relatively faint in the lower-ionization emission represented by the redder portions of the image, while the inner nebular region is dominated by emission from more highly ionized species.
The red-orange envelope is particularly prominent around the circumference of the nebula. In the lower-left panel, labelled as an enhancement of S II and Hα, the red coloration emphasizes regions where hydrogen recombination emission and singly ionized sulphur emission are strong. Hα arises when an electron recombines with ionized hydrogen and subsequently cascades through the hydrogen energy levels, producing the familiar 656.3-nm Balmer emission line. S II emission, meanwhile, traces relatively low-ionization gas. Consequently, the red outer structure provides a useful visual representation of the nebula's comparatively lower-ionization zones, especially toward the outer shell and interfaces with the surrounding material.
The lower-right panel, identified as an enhancement of Hα and O III, produces a conspicuous transition from red through yellow-green into blue. The strong [O III] emission is characteristic of highly ionized regions. In particular, the familiar nebular [O III] lines at approximately 495.9 and 500.7 nm are excited forbidden transitions by collision of doubly ionized oxygen, O²⁺. Their prominence toward the inner nebula indicates that the gas there is exposed to the energetic ultraviolet radiation field of the central star. Thus, the blue-green interior is not simply a region of different optical colour: it is a visual proxy for a different ionization state of the plasma.
The upper-right panel, labelled “Nebula only – enhanced,” is especially useful for appreciating the morphology independently of the surrounding stellar field. Enhancement reveals an extensive network of extremely faint, irregular emission surrounding the bright principal ring. The outer material is highly filamentary and clumpy, with numerous wispy structures extending radially and tangentially away from the principal shell. These features are evidence that the nebula is not a geometrically perfect sphere. Instead, the circumstellar material has a complex density distribution containing knots, filaments, cavities, and regions of differing ionization.
One of the most important structural characteristics visible in the figure is the nested-shell architecture. The bright annulus does not have a single sharp boundary. Instead, it contains multiple zones of emission, with the inner blue region transitioning through greenish/cyan emission into a bright pale or yellow-green rim, followed by the dominant orange-red envelope. Such stratification is expected when ionizing radiation propagates through an expanding, nonuniform circumstellar shell. The innermost regions are exposed to the hardest part of the stellar ultraviolet spectrum and therefore contain ions requiring greater ionization energies, whereas progressively more weakly ionized species become important farther from the central star.
The nebula's central blue region is consequently of considerable physical significance. It represents a comparatively high-excitation component of the ionized gas. The strong blue/cyan appearance in the processed images is dominated by the selected emission-line mapping, particularly [O III], rather than indicating that the gas is literally blue in the conventional sense. The region contains ionized material whose emission is strongly influenced by the intense ultraviolet radiation of the central star. The transition from this high-excitation interior to the lower-ionization outer envelope records the changing balance between photoionization, recombination, gas density, and the radiation field with increasing distance from the star.
The bright inner rim is particularly prominent as a pale yellow-green or whitish ring. This region represents a zone where several emission components overlap in the composite rendering. Physically, it can be understood as a relatively dense, strongly emitting portion of the nebular shell in which the ionization structure changes rapidly with position. The brightness is therefore a consequence of both the local gas density and the efficiency with which the gas converts stellar ultraviolet energy into optical emission lines.
Beyond the principal ring, the image reveals an extensive diffuse halo of ionized and partially ionized material. In the enhanced upper-right panel this halo becomes dramatically apparent as a web of delicate, smoky filaments. These structures are scientifically important because they demonstrate that the visible bright ring does not encompass the entire circumstellar ejecta. Material expelled during earlier stages of the progenitor star's late evolution can persist outside the principal bright shell, while subsequent changes in the stellar wind and ionizing radiation field alter its density and ionization state.
The numerous small, compact structures embedded in the shell are also noteworthy. The Helix is famous for its cometary knots: dense molecular or dusty condensations embedded within the ionized nebula, many of which possess elongated, radially oriented tails. At the resolution and processing shown here, the figure primarily emphasizes the larger-scale shell and filamentary emission, but the irregular texture and small-scale condensations are consistent with the highly structured environment produced by these dense knots. Their existence demonstrates that planetary nebulae are not homogeneous clouds of gas; they can contain enormous contrasts in density on comparatively small spatial scales.
The stars scattered across the field provide an additional useful reference. The bright points in the upper-left and other panels are foreground and background field stars, rather than components of the nebular shell. Some show diffraction artifacts or processing-related spikes, while the diffuse nebular emission forms a spatially extended structure around them. Removing or suppressing the stellar field, as in the “nebula only” panel, dramatically increases the visibility of the extremely faint circumnebula structures.
What the four panels reveal
The comparison is particularly effective because each processing approach highlights a different aspect of the nebula:
Taken together, the panels show that the Helix is best understood not as a simple glowing ring, but as a three-dimensional, evolving photoionized plasma with nested ionization zones and a highly structured circumstellar envelope. The apparent ring is a projection of an expanding shell or complex system of shells along the observer's line of sight. Its bright inner regions are associated with higher-excitation gas illuminated by the hot central star, while the outer redder structures trace progressively lower-ionization material. The tenuous filaments extending beyond the principal shell record older and more diffuse circumstellar material and the interaction between the nebular gas and its surrounding environment.
In evolutionary terms, the Helix represents a relatively brief phase in stellar evolution. The progenitor star previously underwent substantial mass loss, ejecting its outer atmospheric layers into circumstellar space. As the stellar core became progressively hotter, its ultraviolet radiation ionized those expelled layers, causing them to fluoresce and emit the spectacular spectrum recorded in narrowband astronomical images. The central star is now evolving toward a compact white-dwarf remnant, while the nebular material continues to expand, dilute, recombine, and disperse into the interstellar medium.
Thus, the uploaded image captures several fundamental physical processes simultaneously: stellar mass loss, photoionization, radiative cooling, recombination, chemical excitation, density structuring, shell expansion, and the gradual dispersal of stellar material into interstellar space. The extraordinary contrast between the blue-green high-excitation interior, the bright intermediate ionization zone, and the red-orange outer envelope is essentially a map of how the central star's ionizing radiation interacts with the density and composition of its former atmosphere.
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| NASA APOD. |
https://science.nasa.gov/image-article/apod-2026-august-6-new-sharpest-image-of-the-sun-uncovers-instability/
"This image captured in blue light and shown in false colour shows instability in the plasma at micro levels long hypothesised to exist.
Kurt thought this was so interesting that we decided to repost it"- Joel Cairo CEO of the JPO the UK:s most Easterly.
This wide-field deep-sky photograph captures a dense section of the galactic plane of the Milky Way, centred along the dust lanes and rich star fields of the Summer Triangle region (spanning Cygnus, Aquila, and Lyra).
The Galactic Plane & Interstellar Medium
Running diagonally through the frame is the prominent, luminous swath of our galaxy’s spiral arm structure. The bright golden and warm orange glow consists of resolved and unresolved background stellar populations within the galactic disk. Interspersed throughout this region are dark nebulae—obscuring interstellar dust clouds composed of microscopic carbon and silicate grains that absorb and scatter visual wavelength light from the dense star fields lying directly behind them (notably forming parts of the Great Rift complex).
Emission & Dust Regions
Surrounding the primary galactic core structure are delicate reddish and deep magenta hues, indicating Hα (Hydrogen-alpha) ionized gas regions (H II regions) where intense ultraviolet radiation from hot, young stars energizes the surrounding interstellar gas.
Here are the key nebulous regions displayed in the photograph of the Milky Way:
1. North America Nebula (NGC 7000): This is the prominent, diffuse reddish-orange glowing structure located in the upper-right section of your image. Its characteristic shape, resembling the continent (specifically the Gulf of Mexico), is sculpted by a thick, intervening dark dust lane. This massive $H\text{ II}$ region is one of the brightest emission nebulas visible, glowing as hydrogen gas is ionized by nearby hot stars.
2. Pelican Nebula (IC 5070): Located immediately adjacent to the North America Nebula, and separated from it by the primary dark molecular cloud, is the Pelican Nebula. While visually part of the same complex, it appears as a distinct lobe, and in this wide-field view, it forms the upper portion of the large glowing mass containing NGC 7000.
3. Sadr Region (IC 1318 / Gamma Cygni Nebula): Running centrally through the densest part of the Milky Way core in your frame is the complex around the star Sadr. The large, spread-out glow in the lower-right section is IC 1318, also known as the Gamma Cygni Nebula. This vast emission complex is heavily fragmented by dark dust lanes (the Great Rift), defining multiple lobes including the Butterfly Nebula (near the centre) and the Cygnus Star Cloud itself, which dominates the lower-right bright region.
4. The Great Rift (and dark nebulae): Although not a glowing nebula, the Great Rift is essential for defining the visible structures. The large, black channel running diagonally down the centre of the image, dramatically separating the bright star fields on the right from the sparser ones on the left, is composed of dense, opaque interstellar dust that obscures the light from the background stars. Numerous individual "dark nebulae" are catalogued within this feature.
By recognizing these major formations, we can better appreciate the complex interplay of gas, dust, and stars in this extraordinarily rich section of our galaxy.
Transient Phenomena (Meteors)
In the lower-left quadrant of the frame, three parallel, highly linear light trails cut across the background star field:
Perseid / Delta Aquariid Activity: Late July marks the onset of the Perseid meteor shower, operating concurrently with the Southern δ-Aquariids peak. These crisp streaks represent meteoroids—small remnants of cometary dust (such as 109P/Swift-Tuttle for the Perseids)—entering Earth's upper mesosphere at velocities between 40 km/s and 60 km/s.
Atmospheric Ablation: The resulting friction superheats the surrounding atmospheric gas, creating brief, highly ionized plasma columns that appear as precise linear streaks against the background sky.
Stellar Dynamics
Across the frame, a distinct colour gradient highlights stellar spectral classes: bright blue stars indicate hotter, high-mass main-sequence objects (spectral types O and B), while yellow and reddish points denote cooler main-sequence stars and red giants (spectral types K and M).
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| The Full Moon over the Jodrell Plank Observatory last night. Handheld Canon 600d DSLR with EOS lens at f=300mm. Image credit: Kurt Thrust. |
" Last night you could smell the forest fire at Dunwich Heath some 19 miles distant from the Observatory. The Moon looked big and yellow above the shrubbery. It was a pretty, hot and disturbing night in Suffolk. Thankfully, today is cooler and the wind direction has changed taking the fire, flames and smoke towards the sea. Our thoughts and best wishes go to the many fire-fighters who have worked throughout the day and night to keep us all safe in East Suffolk." - Joel Cairo CEO of the JPO - the UK's most easterly astronomical observatory.
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| Modified RGB-SHO colour palette. Showing the Pillars of Creation centre right. Image processing credit: Kurt Thrust- JPO. |
| Part of the Eagle Nebula captured with the PIRATE robotic telescope, Tenerife. Credit: Open Science Observatories, Open University, telescope.org. Base Image unmodified SHO palette |
The Pillars of Creation are a 'Stellar Battleground', which represent an intense cosmic tug-of-war. The Pillars are constantly bombarded and eroded by ultraviolet radiation and powerful winds from massive, hot stars. As this fierce light erodes the surface of the gas columns, it compresses the dense pockets of gas inside. These pockets act like incubators for new star systems, triggering further stellar birth". - Karl Segin Outreach Coordinator at the JPO.
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NASA, ESA/Hubble and the Hubble Heritage Team | : |
" I happened to notice a brightening on the penumbral boundary of sunspot AR4482 and wondered whether we had captured a bright solar flare. I had read that sometimes this can be achieved when imaging the Solar Photosphere in white light. I decided to ask our visiting expert, Professor Chat, and the following are his observations based on the above image". - Kurt Thrust current Director of the Jodrell Plank Observatory.
"Short take: your composite does show a plausible transient brightening near the penumbral boundary of AR4482, but from this image alone I can’t confirm it’s a flare. It could also be a facular/leaf‑like penumbral grain cluster, a small Ellerman bomb–type event, or processing/artifact from channel mis‑registration.
What I see
A compact, high‑contrast bright patch on the penumbra’s outer edge (your arrow), present in the lower panel but muted in the upper. That matches where small flares and moving magnetic features often light up.
The “bright in blue channel” note suggests it’s stronger shortward of green/red, which is consistent with continuum/near‑UV enhancement seen in white‑light microflares—but also with scatter or sharpening halos."