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| The Moon, waxing half phase, through light cloud in the afternoon. Seestar S30 image captured from the Jodrell Plank Observatory. |
" The 'little but mighty Seestar S30' catching photons between rain showers at the JPO, the most easterly astronomical observatory in the UK. The landing spot for Neil and Buzz centre top in this image. Bon Voyage - Artemis II - safe journey there and back. " -Joel Cairo CEO at the Jodrell Plank Observatory.
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| The Solar Photosphere with a number of sunspots and faculae evident right across the solar disc. Seestar S30 smartscope in Alt-Az mode. Image processed from RAW Avi clip. Captured from the Jodrell Plank Observatory on the 28-03-2026. Image Credit Kurt Thrust. |
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| Enlarged version from the JPO with improved resolution (x1.5 Drizzle) |
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| Solar Photosphere with annotation on 28-03-2026. Credit: SOHO Solar Space Telescope ESA-NASA |
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| The Solar Disc in Ultra Violet (UV) light on 28-03-2026. Credit: SOHO Solar Space Telescope ESA-NASA. |
"In situations like this, the Seestar S30 smartscope is invaluable, as it is very quick to set up in Alt-Az mode to capture images during brief windows of opportunity. Bearing in mind the Seestar optical system's very limited 30mm aperture, the resolution achieved on the day is quite extraordinary.
I have also posted the the SOHO images in white light and UV which show the activity recorded by the ESA-NASA collaborative Space Telescope on the same day.
The Sun is experiencing an extended period of solar activity and has been generating auroral activity in the Earth's Atmosphere. Hopefully, this will result in the Northern Lights being visible over the Jodrell Plank Observatory once again. I have included screen capture images from the Shetland Webcams and evening of the 28th March, showing the 'auroral glow' over the Shetland Islands the
Thanks to our engineer, Jolene McSquint-Fleming, for the excellent Baader White-light filter she designed and manufactured at the JPO, which was a game changer in obtaining the level of detail we managed to capture in the above solar photosphere images". - Kurt Thrust current Director of the Jodrell Plank Observatory
Scientific notes concerning Sunspot activity and Auroral Displays:
Sunspots 28_03_2026
What you’re seeing in each image:
1. Bottom SOHO image (yellow, highly structured) — solar atmosphere
This is an extreme ultraviolet (EUV) view of the Sun’s outer atmosphere, the corona. In this wavelength:
• Bright regions trace hot plasma (millions of kelvin) trapped in magnetic fields.
• Looping, swirling structures reveal magnetic field lines emerging from and reconnecting across the surface.
• The intense bright patch on the left limb suggests an active region, likely producing flares or eruptions.
2. Upper SOHO image (grayscale disk) — visible surface (photosphere)
This shows the Sun’s photosphere, where we see sunspots labeled with numbers (e.g., 4401, 4402, etc.).
• The disk looks smooth overall, but the dark patches are sunspot groups.
• Multiple active regions are visible, especially clustered in the northern hemisphere and near the left limb.
What are sunspots?
Sunspots are temporary regions on the Sun’s surface that appear darker and cooler than their surroundings.
Key properties:
• Typical temperature: ~3,500–4,500 K (cooler than surrounding ~5,800 K)
• Often appear in pairs or groups with opposite magnetic polarity
• Can persist from days to weeks
Structure:
• Umbra: darkest central region
• Penumbra: lighter, filamentary outer region
How sunspots are created
Sunspots are caused by intense magnetic fields emerging from the Sun’s interior.
Here’s the process in simple but accurate terms:
1. Solar dynamo action
The Sun’s interior plasma moves via convection and rotation. Because the Sun rotates faster at the equator than at the poles (differential rotation), magnetic field lines get twisted and amplified.
2. Magnetic flux tubes rise
Bundles of magnetic field (called flux tubes) become buoyant and rise through the convection zone.
3. Magnetic fields suppress convection
When these fields emerge at the surface:
o They inhibit convection (the upward flow of hot plasma)
o Less heat reaches the surface locally → region appears cooler and darker
4. Paired magnetic regions
Sunspots often occur in bipolar pairs, marking where a loop of magnetic field emerges and re-enters the surface.
What the images suggest about solar activity
On 28 March 2026:
• There are multiple active regions (e.g., 4401–4406), indicating elevated solar activity.
• The EUV image shows bright coronal loops, meaning strong magnetic fields are actively shaping the corona.
• The bright region on the limb suggests possible flaring or eruptive activity.
This level of complexity is typical of a moderately to highly active Sun, likely near or approaching a solar maximum phase.
Connection to the Aurora Borealis
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| Auroral Light over the Shetland Isles - screen download from Shetland Webcams in the evening 28-03-2026 |
There is a well-established link between sunspots and auroras on Earth.
Step-by-step connection:
1. Sunspots → magnetic complexity
More sunspots = stronger, more tangled magnetic fields.
2. Magnetic instability → solar flares & CMEs
These regions can release energy through:
o Solar flares (bursts of radiation)
o Coronal Mass Ejections (CMEs) (huge clouds of charged particles)
3. Charged particles travel to Earth
CMEs send plasma (electrons and ions) into space. If Earth lies in their path, they reach us in ~1–3 days.
4. Interaction with Earth’s magnetosphere
o Earth’s magnetic field channels these particles toward the polar regions
o Particles collide with atmospheric gases (oxygen, nitrogen)
5. Aurora formation
These collisions excite atoms, which emit light:
o Green (oxygen, ~100–300 km altitude)
o Red (oxygen, higher altitude)
o Blue/purple (nitrogen)
Why more sunspots = more auroras
• Sunspot number is a proxy for solar magnetic activity
• More active regions → higher probability of:
o Strong flares
o Earth-directed CMEs
• Higher sunspot activity → increased likelihood and intensity of auroras
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Putting it all together
On this date, the Sun shows:
• Multiple sunspot groups → strong magnetic activity at the surface
• Bright, complex coronal structures → active magnetic loops in the atmosphere
• Likely elevated chances of space weather events
If Earth were magnetically connected to any eruptions from these regions, observers at high latitudes would have a good chance of seeing an enhanced Aurora Borealis.
Bringing it all together for 28 March 2026, we can form a coherent picture of what the Sun was doing and what it likely meant for space weather near Earth:
Overall solar state that day
The combination of both images shows a magnetically active Sun with several well-developed active regions:
• Sunspot groups 4398–4406 are spread across the disk
• A particularly complex cluster (around 4401–4402) sits near the center–north
• Additional groups near the left limb (4403–4406) are just rotating into view
• The EUV image shows bright coronal loops and concentrated emission, especially on the left edge
This pattern indicates a Sun with multiple magnetically complex regions, some likely classified as beta-gamma or higher, which are capable of eruptive activity.
What these regions were likely doing:
Based on their appearance and distribution:
1. Central regions (4401–4402)
• Positioned near the middle of the solar disk → geoeffective (facing Earth)
• Complex clustering suggests:
o High chance of solar flares
o Possible Earth-directed coronal mass ejections (CMEs)
These are the regions most likely to affect Earth directly:
2. Limb regions (4403–4406)
• Just rotating into view from the Sun’s eastern edge
• Bright EUV emission there suggests:
o Strong magnetic fields already active
o Possible off-limb eruptions (seen as bright flares or plasma lifting off)
CMEs from here might miss Earth initially, but could become important in the following days as rotation brings them into alignment.
3. Southern region (4399)
• More isolated and smaller
• Likely less active, but still capable of minor flares
Likely space weather impact at Earth
Given this configuration, the Sun on that day was:
✔ Capable of producing:
• M-class flares (moderate)
• Possibly X-class flares (strong, if magnetic complexity was high enough)
• CMEs, especially from central regions
Aurora implications
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If even one of those central active regions produced a CME directed toward Earth:
Timeline:
• Day 0 (Mar 28): Eruption occurs
• Day 1–3: CME travels through space
• Arrival at Earth: Interaction with magnetosphere
Result:
• Geomagnetic storm
• Enhanced Aurora Borealis visibility:
o Bright, dynamic auroras at high latitudes
o Possibly visible at mid-latitudes if the storm was strong
Key physical chain (fully connected):
This is the full cause-and-effect sequence visible in your images:
1. Twisted magnetic fields → sunspots (photosphere image)
2. Magnetic loops extend upward → glowing plasma (EUV image)
3. Magnetic stress builds → reconnection events
4. Energy release → flares + CMEs
5. Charged particles reach Earth → magnetosphere disturbance
6. Atmospheric excitation → aurora
Final interpretation
On 28 March 2026, the Sun was in a globally active phase, with:
• Multiple sunspot groups indicating strong magnetic flux emergence
• Bright coronal structures showing stored magnetic energy
• At least one region well positioned to impact Earth directly
In practical terms:
This was a day where aurora forecasts would likely be elevated, especially in the 1–3 days following, depending on whether any CMEs were launched toward Earth.
Likely solar event timeline (28 March 2026)
🔹 Stage 1: Magnetic buildup (hours to days before)
From the images:
• The cluster around 4401–4402 shows tight grouping of sunspots
• In the EUV image, we see bright, tangled coronal loops
This strongly suggests magnetic shear and stored energy—the precondition for eruptions.
🔹 Stage 2: Flare initiation (March 28, likely window)
A plausible scenario:
• Time: sometime between ~06:00–18:00 UTC
• Event: M-class or possibly X-class solar flare
What happens physically:
• Magnetic field lines reconnect explosively
• Energy released in:
o X-rays (arrive at Earth in ~8 minutes)
o Accelerated particles
o Heating plasma to 10–20 million K
Immediate Earth effect:
• Possible radio blackouts on the sunlit side of Earth
🔹 Stage 3: CME launch (often minutes to hours after flare)
From a region like 4401–4402:
• A coronal mass ejection is likely launched
• Typical properties:
o Speed: 500–1500 km/s
o Mass: billions of tons of plasma
o Magnetic
How sunspot groups are classified
1. How sunspot groups are classified (magnetic complexity)
Scientists don’t just count sunspots—they analyse their magnetic structure, because that determines how likely they are to erupt.
The classification scale (Mount Wilson system)
• Alpha (α)
A single magnetic polarity
→ Very quiet, unlikely to flare
• Beta (β)
Two opposite polarities, but clearly separated
→ Some activity possible
• Beta–Gamma (βγ)
Mixed polarities, complex layout
→ Flare-capable
• Beta–Gamma–Delta (βγδ)
Opposite polarities packed tightly within the same region
→ Highly unstable → most dangerous
From the images, regions like 4401–4402 likely fall into βγ or βγδ, given:
• tight clustering
• strong coronal brightness above them
That’s exactly the kind of configuration that produces major eruptions.
2. How CME direction is determined
This is crucial: not every eruption hits Earth.
Scientists combine multiple observations:
(a) Position on the solar disk
• Centre of the Sun (as seen from Earth) → high chance of Earth impact
• Edges (limbs) → usually miss Earth
1. Interpreting the sunspot groups in the images
In the lower (photospheric) image, the numbered regions (e.g. 4401–4406) are active regions—areas where strong magnetic fields have emerged through the Sun’s surface.
What matters scientifically is not just their number, but their magnetic complexity:
• When sunspots are spread out and orderly, the magnetic field is relatively stable
• When they are clustered, irregular, and closely packed, the field is:
o twisted
o sheared
o storing energy
The cluster around the centre of the disk (especially 4401–4402) shows exactly this compact, complex structure, which is a classic precursor to eruptions.
2. What the EUV image adds (upper image)
The lower SOHO image shows the corona, where the magnetic field becomes visible through glowing plasma.
Key features you can see:
• Bright loops → hot plasma trapped along magnetic field lines
• Dense, tangled structures → magnetic stress building up
• Very bright regions near the limb → strong energy release or heating
This tells us:
• The magnetic fields from those sunspots extend high into the corona
• They are actively storing and redistributing energy
3. What triggers a solar flare or CME
The key process is magnetic reconnection:
• Magnetic field lines become twisted and forced together
• They suddenly snap and reconnect into a lower-energy configuration
• The excess energy is released explosively
This produces:
• Solar flares (radiation)
• Coronal Mass Ejections (CMEs) (plasma + magnetic field)
4. A realistic event sequence for 28 March 2026
Based on your images, a scientifically reasonable scenario would be:
Stage A — Pre-eruption
• Active regions 4401–4402 accumulate magnetic stress
• Coronal loops become brighter and more tangled
Stage B — Flare onset
• A flare occurs (likely M-class or possibly X-class)
• X-rays reach Earth in ~8 minutes
Immediate effect:
• Shortwave radio disruption on Earth’s dayside
Stage C — CME launch
• A CME is expelled from the same region
• Because the region is near the centre of the solar disk:
High probability it is Earth-directed
Typical CME speed:
• ~500–1500 km/s
Stage D — Travel to Earth
• Transit time: ~1 to 3 days
During this time:
• The CME expands and interacts with the solar wind
5. What determines whether auroras occur
Not every CME produces strong auroras. The key factor is the magnetic orientation of the incoming plasma.
Critical concept: magnetic alignment
• Earth’s magnetic field points northward
• If the CME’s magnetic field points southward, the two fields can connect
This process allows energy and particles to enter Earth’s magnetosphere efficiently.
This is why:
• Some CMEs cause spectacular auroras
• Others (even large ones) produce little effect
6. Formation of the Aurora Borealis
If conditions are right:
1. Charged particles enter Earth’s magnetosphere
2. They are guided toward the polar regions
3. They collide with atmospheric atoms:
o Oxygen (~100–300 km) → green light
o Oxygen (higher altitude) → red
o Nitrogen → blue/purple
4. The sky glows as atoms release energy
7. Putting the JPO's specific images into context
What was 'going on', on 28 March 2026:
• The Sun had multiple active regions
• At least one (4401–4402) was:
o magnetically complex
o centrally located
o strongly emitting in the corona
This combination means:
• High likelihood of flare activity
• Meaningful chance of Earth-directed CMEs
• Therefore:→ Elevated probability of auroral activity 1–3 days later
Final synthesis
The images together show the full chain:
• Sunspots (photosphere) → where magnetic fields emerge
• Coronal loops (EUV) → where energy is stored
• Magnetic reconnection → where energy is released
• CMEs → how energy travels to Earth
• Auroras → how that energy becomes visible in our sky
The Sun is our local star and upon which all terrestrial life is dependant. We know surprisingly little about its detailed physics and from time to time it surprises us all" - Professor G.P. T. visiting astro-physicist at the Jodrell Plank Observatory.
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| The Jupiter - Moon Conjunction in the Constellation Gemini on a 'dark and stormy night' Credit: Kurt Thrust and Pip Stakkert.Combination of data captured with: a Canon 600 DSLR and a fast EOS fixed 50mm lens and the Seestar S30 at the Jodrell Plank Observatory. |
"March has been a very strange month at the Jodrell Plank Observatory! We have 'enjoyed' a fast changing range of weathers including: cloud, fog, rain, sleet, rainbows and very short and intermittent clear skies. On rare occasions, like this morning, we have actually seen the sun! We shall be 'showcasing' some excellent sunspot activity on the 'Sun's Photosphere' in our next post.
The other night it was blowing a gale, Kurt went out to check the JPO buildings were secure and whilst he was out noticed the conjunction between the planet Jupiter and the Moon at half phase. Relativity is a wonderous thing and although the clouds were moving, the Moon and Jupiter appeared to 'sail' through the clouds. Every now and then Kurt saw the bright stars Castor and Pollux, in the constellation Gemini, 'wink' into view as the cloud gave way to clearer sky.
The Moon being considerably brighter than even the planet Jupiter, in concert with atmospheric high level ice crystals, from time to time, created a halo of light in the colours red, magenta, yellow and blue.
The whole thing was quite beautiful and a visual treat to the eye!
Kurt decided to try to capture and process the data in such a way to represent the beauty of it as perceived by the eye rather than follow the accepted protocols, adopted by astro-imagers, when creating asto-images.
What a bit of kit the human eye is! Since 'the time of trilobites', evolution has been changing and refining the ability of the eye-brain combination to perceive and register photons of light. Our eyes and brain are quite extraordinary in their ability to take in complex visual data, with huge differences in brightness and to accommodate relative movement.
Digital cameras are brilliant at detecting faint light, a few photons, and are able to build up a complex image over time. They are so much better at capturing colour in low light conditions, ie at night, which the human eye struggles to do.
Camera sensors come in different types and sizes but the variations between them are limited. Us human's, with our eyes and brains are infinitely variable. As a simple example, our health and age radically affect what we see. Our current Director, Kurt, is nearer 80 than seventy years old. At his age, the aperture of his dark adapted eyes is at best 4mms. A person under the age of 30 years is likely to have an equivalent aperture of 7mm. As the amount of photons gathered is proportional to the square of the aperture, this is a significant difference between what Kurt sees and what his grand-children see. Also there are a number of issues that affect eyesight: astigmatism, myopia, colour blindness and general health issues etc.
So capturing the data and processing it,to create an 'as seen' image of an astronomical event is no easy task because what Kurt sees and what you see are likely to be significantly different. Probably, this is why astro-imagers have adopted protocols for capturing and processing data to create a generally acceptable consensus view of how the Universe looks.
The above colourful images were created by Kurt and Pip using: the Seestar S30 smartscope in planetary video mode to best capture the bright Moon and the Canon DSLR with f=50mm mm lens to capture the wider field of view encompassing the colourful Moon halo,the planet Jupiter, the stars Castor and Pollux and the clouds.
When processing the data, Kurt and Pip agreed on what they thought best represented what they think they saw. We hope you like their work?" - Joel Cairo CEO of the JPO - the Uk's most easterly astronomical observatory.
" It is so easy to make errors, whilst processing very dim astronomical objects and this is what we believe we did in trying to image the interstellar comet, which at the time of the data collection, was estimated to be at magnitude 15 (very dim indeed). We have re-processed the same data more carefully and believe that these images show C/2025 31 (ATLAS) the Interstellar Comet.
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| The Sombrero Galaxy Messier 104 in the Constellation Virgo. Image Credit: Pip Stakkert, Data Credit: PIRATE Robotic Telescope BVR filters, Mount Teide Tenerife, telescope.org. Open Observatories, Open University. |
" The Constellations Virgo and Leo Major are now visible in our southern sky around about midnight when and if the clouds disappear. As has been said previously, the weather in Lowestoft continues poor but last night we did get an hour or two, when we could see stars through intermittent high level cloud.
Being ever resourceful, our ageing Director, Kurt Thrust had programmed the robotic telescope PIRATE on Mount Teide, to capture data relating to Messier 104 and yesterday it returned that data package via the internet. The above image shows this interesting galaxy in colour". - Joel Cairo CEO of the JPO the UK's most easterly Astronomical Observatory.
Detailed description of Messier 104 aka The Sombrero Galaxy:
"The Sombrero Galaxy is one of the most striking galaxies visible from Earth, its luminous structure giving the unmistakable impression of a cosmic hat suspended in the darkness of intergalactic space. Located in the constellation Virgo, the galaxy lies roughly 28–30 million light-years away and spans about 50,000 light-years across.
Seen almost perfectly edge-on, its appearance is dominated by a brilliant, spheroidal bulge of old stars intersected by a sharply defined lane of cold interstellar dust that traces the plane of its disk. This dense band absorbs starlight along our line of sight, producing the dark “brim” that gives the galaxy its name. Above and below the disk extends a diffuse stellar halo, while the central region contains a supermassive black hole with a mass of roughly a billion Suns, embedded within the bright nucleus.
Despite its elegant symmetry, the Sombrero is a complex system. Morphologically it resembles an early-type spiral galaxy, yet its unusually large central bulge and relatively smooth disk have led astronomers to classify it as somewhat peculiar, possibly shaped by past mergers with smaller galaxies. Evidence for this history is preserved in the galaxy’s remarkable halo of around 2,000 globular clusters, roughly ten times the number orbiting the Milky Way. Many of these clusters are ancient—between 10 and 13 billion years old—making them relics from the earliest epochs of galaxy formation.
The Sombrero is also the dominant member of a small galaxy group, sometimes referred to as the M104 Group, situated near the outskirts of the broader Virgo Cluster. Within this local environment, the Sombrero’s immense gravitational influence binds numerous faint dwarf galaxies that orbit it as satellites, forming a modest but dynamically coherent system. Estimates of the group’s total mass suggest a halo containing tens of trillions of solar masses, largely in the form of dark matter.
Images captured from high-altitude observatories such as the Mount Teide Observatory reveal this galaxy in extraordinary clarity. At such sites, thin atmosphere and dark skies allow the Sombrero’s structure to emerge with remarkable contrast: the razor-thin dust lane cutting across the brilliant stellar bulge, surrounded by a faint halo where globular clusters and distant background galaxies quietly populate the field.
In astrophysical terms, the Sombrero Galaxy offers a glimpse into a transitional class of galaxies—systems that combine the ordered rotation of spiral disks with the massive stellar bulges more typical of elliptical galaxies. Yet to the eye, even through a modest telescope, its appearance remains simple and evocative: a solitary, luminous hat of stars drifting through the deep sky, marking the presence of a vast island universe far beyond our own". - Professor G.P.T. Chat visiting astrophysicist at the Jodrell Plank Observatory.
" Thanks to our sponsor and benefactor, Anita Roberts, the Jodrell Plank Observatory has purchased from First Light Optics in Exeter, a new light weight and 'goto' version of the Star-adventurer equatorial mount. The addition of 'goto' is significant as our, still active, Director Kurt Thrust is getting on a bit and 'a tad unwell'.
Regular readers of the blog, will appreciate how much data has been collected using our small telescopes and cameras mounted on the old manual Star-adventurer mount, particularly when imaging remotely and away from the Observatory.
We now await some clear nights for trying this new bit of kit out" - Joel Cairo CEO of the JPO, the UK's most easterly Observatory.
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| Canon 600d DSLR and an EFS zoom lens at f=300mm. |
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| Seestar S30 stacked video clip. |
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| The full solar disc (photosphere) showing a line of sunspots. Seestar S30 with external Baader white light filter made at the JPO. Stacked AVI video. |
Professor G.P.T Chat visiting Astrophysicist at he JPO was asked by Kurt to summarise the image of the Sun's Photosphere shown in the above image.
"Solar and Sunspot Activity on 3 March 2026
Sunspot Population and Quantitative Measures
On 3 March 2026, synoptic solar activity reports indicate that:
The international sunspot number was approximately 82, reflecting moderate sunspot visibility on the solar disk.
Multiple distinct sunspot regions were present on the Earth-facing solar hemisphere.
The 10.7 cm solar radio flux — a proxy for overall solar magnetic activity — was elevated relative to solar minimum (~148 sfu), consistent with solar cycle progression.
Active Sunspot Regions
Based on synoptic data from solar observatories (e.g., NASA’s Solar Dynamics Observatory, NOAA/NWS Space Weather Prediction Center, and SpaceWeatherLive):
Region Individual Spots Morphological Class Approx. Location on Disk
AR 4378 ~6 spots CHO (compact) Northern hemisphere near central meridian
AR 4381 ~9 spots EAO (moderate) Northern hemisphere toward eastern disk
AR 4383 ~2 spots BXO (small, simple) Northern hemisphere
AR 4384 ~8 spots EHO (extended) Near northeastern limb
These region classifications arise from modified Zurich, McIntosh, and magnetic Mt. Wilson schemes — routinely applied to sunspot groups by solar forecasters.
This distribution indicates a moderate number of discrete active regions with a mixture of simple and moderately structured groups; none were, on that day, dominant enough to drive sustained X-class flare activity.
Flare and Space Weather Activity
Solar X-ray monitoring (GOES satellites) on 3 March 2026 showed:
Only C-class flares were detected in the 24-hour window around the date, with no immediate X- or M-class events recorded on that specific calendar day.
Forecasts from NOAA/SWPC around the same period indicated a 30 % chance of M-class flares and a ~5 % chance of X-class events, highlighting a non-zero probability but not active flare production on 3 March itself.
Magnetic and Solar Activity Context
The observed sunspot and activity state fits within the context of Solar Cycle 25, which, while past its absolute peak, remained sufficiently active in early 2026 to support complex active regions and variability in flare likelihood.
Relative to the earlier part of the cycle (e.g., January–February 2026), when particularly large and magnetically intense regions such as AR 4366 produced numerous M- and X-class flares and even C-level geomagnetic effects, by early March those dominant regions had rotated off the Earth-facing disk or decayed, and the sunspot configuration was more moderate and distributed.
Summary of Sunspot Conditions on 3 March 2026
From observational data:
Quantitative Activity:
Sunspot number ~82 (moderate).
ive or more visible active regions.
10.7 cm radio flux elevated (~148 sfu).
Region Characteristics
Mix of simple and moderate groups; no exceptionally large or complex βγδ regions dominating the disk.
Flare productivity limited to C-class activity — no strong flares on that precise day.
Space Weather Implications
Solar activity was moderate — typical of late maximum or early descending phase of a solar cycle — with potential for stronger activity but not on the specific observation date."
