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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
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. Upper 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. Lower 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
• Therefore:
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 your 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 upper 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
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