Science

Northern Lights: Stargazers share snaps of aurora seen in the UK, US and Canada as solar storm hits

Lucky stargazers have taken to social media to share stunning photos of the Northern Lights seen in the skies above the UK, US and Canada last night.

The typically green and pink light shows occur when electrically charged particles from the Sun excite gases in the Earth’s atmosphere, causing them to glow.

The wavy patterns they assume — which can resemble curtains of light — reflect the lines of force in the Earth’s geomagnetic field along which the solar particles travel.

Normally, the aurorae are only visible at higher latitudes, centred around Earth’s magnetic poles, but yesterday’s huge solar storm increased their range. 

Scroll down for video

Lucky stargazers have taken to social media to share stunning photos of the Northern Lights seen in the skies above the UK, US and Canada last night. Pictured: photographer Jeanine Holowatuik posted this shot of the Northern Lights seen last night over Saskatchewan, Canada

The typically green and pink light shows occur when electrically charged particles from the Sun excite gases in the Earth's atmosphere, causing them to glow. Pictured: the northern lights as seen over Corman Park No. 344 in Saskatchewan, Canada, last night

The typically green and pink light shows occur when electrically charged particles from the Sun excite gases in the Earth’s atmosphere, causing them to glow. Pictured: the northern lights as seen over Corman Park No. 344 in Saskatchewan, Canada, last night

The wavy patterns the aurora assume — which can resemble curtains of light — reflect the lines of force in the Earth's geomagnetic field along which the solar particles travel. Pictured: the Northern Lights last night as seen in the skies above Plumas County, Manitoba, Canada

The wavy patterns the aurora assume — which can resemble curtains of light — reflect the lines of force in the Earth’s geomagnetic field along which the solar particles travel. Pictured: the Northern Lights last night as seen in the skies above Plumas County, Manitoba, Canada

'I got to see the #NorthernLights last night and I will never get over it,' wrote Twitter user @ibsmeetsworld, who posted shots of the aurora above Whitehorse, Canada (as pictured)

‘I got to see the #NorthernLights last night and I will never get over it,’ wrote Twitter user @ibsmeetsworld, who posted shots of the aurora above Whitehorse, Canada (as pictured)

Normally, the aurorae are only visible at higher latitudes, centred around Earth's magnetic poles, but yesterday's huge solar storm increased their range. Pictured: the Northern Lights last night seen above the treeline in Whitehorse, Yukon, northwest Canada

Normally, the aurorae are only visible at higher latitudes, centred around Earth’s magnetic poles, but yesterday’s huge solar storm increased their range. Pictured: the Northern Lights last night seen above the treeline in Whitehorse, Yukon, northwest Canada

WHAT IS A SOLAR STORM? 

A solar or geomagnetic storm is a major disturbance of Earth’s magnetosphere – the area around Earth controlled by our planet’s magnetic field.

A solar storm occurs when there is a very efficient exchange of energy from the solar wind into the space environment surrounding Earth 

Earth’s magnetosphere is created by our magnetic field and protects us from most particles the sun emits. 

But when a CME or high-speed stream arrives at Earth it buffets the magnetosphere.

If the arriving solar magnetic field is directed southward it interacts strongly with the oppositely oriented magnetic field of the Earth. 

The Earth’s magnetic field is then peeled open like an onion allowing energetic solar wind particles to stream down the field lines to hit the atmosphere over the poles.   

Source: NASA 

The breath-taking atmospheric displays last night seem to have left an impression.

‘Last night is what dreams are made of #NorthernLights,’ tweeted self-proclaimed aurora chaser Jeanine Holowatuik, of Northern Escape Photography.

Twitter user JessiiVann appears to agree, posting: ‘Please excuse me whilst I cry for the next 6 years, I saw the Northern Lights in Scotland!’

‘I got to see the #NorthernLights last night and I will never get over it,’ added Twitter user @ibsmeetsworld, who posted shots of the aurora above Whitehorse, Canada.

Yesterday’s solar storm — which was forecasted by both the UK’s Met Office and the US’s National Oceanic and Atmospheric Administration — was slower to arrive at Earth than expected.

The organisations had originally said that a ‘coronal mass ejection’ (CME) — a large expulsion of plasma from the Sun’s outer layer — would reach our planet by 5pm BST (12pm EST) yesterday.

However, the space weather event which launched back on October 9 was driven by a slower-than-predicted solar wind and, in the words of physicist Tamitha Skov, arrived ‘fashionably late’.

‘Minor storms may continue into 12 October, before a fast wind from a coronal hole may arrive, perhaps continuing the rather active period of geomagnetic activity,’ the Met Office said yesterday. 

CMEs are caused by stressed, twisted magnetic fields on the Sun releasing their pent-up energy — and therefore tend to originate on the star’s more active regions.

Back in June, researchers from the University of Iowa published a paper in the journal Nature Communications that offered definitive proof that aurorae are caused by ‘Alfven’ electromagnetic waves accelerating electrons toward Earth.

The findings confirmed the 1946 hypothesis of Russian physicist Lev Landau — that electrons ‘surf’ on the electric field of a wave, a process he called Landau damping — and showed that it is this phenomena that leads to the Northern and Southern lights.

‘Measurements revealed this small population of electrons undergoes “resonant acceleration” by the Alfven wave’s electric field,’ said paper author and University of Iowa physicist Gregory Howes.

This, he explained, is ‘similar to a surfer catching a wave and being continually accelerated as the surfer moves along with the wave.’ 

Solar storms drive a process called ‘magnetic reconnection’ in which magnetic field lines break and reform — snapping back toward the Earth ‘like a stretched rubber band that is suddenly released,’ according to Howes.

That snap-back launches Alfven waves that travel towards the Earth along the magnetic field. 

The breath-taking displays last night seem to have left an impression. Twitter user JessiiVann said: 'Please excuse me whilst I cry for the next 6 years, I saw the Northern Lights in Scotland'

The breath-taking displays last night seem to have left an impression. Twitter user JessiiVann said: ‘Please excuse me whilst I cry for the next 6 years, I saw the Northern Lights in Scotland’

'Last night is what dreams are made of #NorthernLights,' tweeted self-proclaimed aurora chaser Jeanine Holowatuik, of Northern Escape Photography. Pictured: the north lights as seen from Sumburgh Head, on the Mainland of Shetland, Scotland

‘Last night is what dreams are made of #NorthernLights,’ tweeted self-proclaimed aurora chaser Jeanine Holowatuik, of Northern Escape Photography. Pictured: the north lights as seen from Sumburgh Head, on the Mainland of Shetland, Scotland

Yesterday's solar storm — which was forecasted by both the UK's Met Office and the US's National Oceanic and Atmospheric Administration — was slower to arrive at Earth than expected. Pictured: the Northern Lights last night seen above the treeline in Whitehorse, Yukon, northwest Canada

Yesterday’s solar storm — which was forecasted by both the UK’s Met Office and the US’s National Oceanic and Atmospheric Administration — was slower to arrive at Earth than expected. Pictured: the Northern Lights last night seen above the treeline in Whitehorse, Yukon, northwest Canada

The organisations had originally said that a 'coronal mass ejection' (CME) — a large expulsion of plasma from the Sun's outer layer — would reach Earth by 5pm BST (12pm EST) yesterday. Pictured: the Northern lights as seen above Scotland last night

The organisations had originally said that a ‘coronal mass ejection’ (CME) — a large expulsion of plasma from the Sun’s outer layer — would reach Earth by 5pm BST (12pm EST) yesterday. Pictured: the Northern lights as seen above Scotland last night

At altitudes below 12,000 miles, where Alfven wave speed exceeds the electron thermal velocity, electrons moving in the same direction as the Alfven wave accelerates.

Traveling at speeds of up to 45 million mph, the electrons ‘stream down along the Earth’s magnetic field,’ Howes explained, ‘eventually colliding with the oxygen and nitrogen atoms and molecules in the thin air of the upper atmosphere.’

That impact causes the shimmering curtain of light we know as the Aurora Borealis.

While this phenomenon has been understood for more than 40 years, a team of physicists led by the University of Iowa simulated it in the lab for the first time.

The researchers conducted numerous simulations using the Large Plasma Device (LPD) at UCLA’s Basic Plasma Science Facility to show Alfven waves accelerated electrons toward Earth, causing the glowing effect of the Aurora Borealis.

‘These experiments let us make the key measurements that show that the space measurements and theory do, indeed, explain a major way in which the aurora are created,’ said co-author Craig Kletzing.

The researchers also recreated Earth’s magnetic field inside a special chamber using the LPD’s powerful magnetic field coils, then generated plasma similar to what exists in space near the Earth.

The space weather event which launched back on October 9 was driven by a slower-than-predicted solar wind and, in the words of physicist Tamitha Skov, arrived 'fashionably late'. Pictured: the Northern Lights as seen last night in the skies above Scotland

The space weather event which launched back on October 9 was driven by a slower-than-predicted solar wind and, in the words of physicist Tamitha Skov, arrived ‘fashionably late’. Pictured: the Northern Lights as seen last night in the skies above Scotland

'Minor storms may continue into 12 October, before a fast wind from a coronal hole may arrive, perhaps continuing the rather active period of geomagnetic activity,' the Met Office said. Pictured: the aurora above Scotland last night, captured by Twitter user @JessiiVann

‘Minor storms may continue into 12 October, before a fast wind from a coronal hole may arrive, perhaps continuing the rather active period of geomagnetic activity,’ the Met Office said. Pictured: the aurora above Scotland last night, captured by Twitter user @JessiiVann

Humans have observed the northern lights for millennia: in ancient Chinese folklore, a young woman witnessing the lights gave birth to Emperor Xuanyuan, the legendary forefather of all Chinese people.

A Norwegian account from 1230 AD attributes the northern lights to the ocean being on fire, while Benjamin Franklin theorized in 1778 that an aurora was caused by snow and ice intensifying electrical charges at the poles.

Some Native American peoples believed the lights were the spirits of their deceased dancing in the sky — and Confederate soldiers seeing the effect during the Battle of Gettysburg assumed its presence so far south meant that God was on their side. 

Humans have observed the northern lights for millennia: in ancient Chinese folklore, a young woman witnessing the lights gave birth to Emperor Xuanyuan, the legendary forefather of all Chinese people. Pictured: the Northern Lights last night in the skies above Edinburgh

Humans have observed the northern lights for millennia: in ancient Chinese folklore, a young woman witnessing the lights gave birth to Emperor Xuanyuan, the legendary forefather of all Chinese people. Pictured: the Northern Lights last night in the skies above Edinburgh

A Norwegian account from 1230 AD attributes the northern lights to the ocean being on fire, while Benjamin Franklin theorized in 1778 that an aurora was caused by snow and ice intensifying electrical charges at the poles. Pictured: the north lights as seen from Sumburgh Head, on the Mainland of Shetland, Scotland

A Norwegian account from 1230 AD attributes the northern lights to the ocean being on fire, while Benjamin Franklin theorized in 1778 that an aurora was caused by snow and ice intensifying electrical charges at the poles. Pictured: the north lights as seen from Sumburgh Head, on the Mainland of Shetland, Scotland

WHAT ARE AURORAS AND WHAT TRIGGERS THE STUNNING NATURAL DISPLAYS?

The Northern and Southern Lights are natural light spectacles triggered in our atmosphere that are also known as the ‘Auroras’.

There are two types of Aurora – Aurora Borealis, which means ‘dawn of the north’, and Aurora Australis, ‘dawn of the south.’

The displays light up when electrically charged particles from the sun enter the Earth’s atmosphere. 

There are two types of Aurora - Aurora Borealis (file photo), which means 'dawn of the north', and Aurora Australis, 'dawn of the south.' The displays light up when electrically charged particles from the sun enter the Earth’s atmosphere

There are two types of Aurora – Aurora Borealis (file photo), which means ‘dawn of the north’, and Aurora Australis, ‘dawn of the south.’ The displays light up when electrically charged particles from the sun enter the Earth’s atmosphere

Usually the particles, sometimes referred to as a solar storm, are deflected by Earth’s magnetic field.

But during stronger storms they enter the atmosphere and collide with gas particles, including hydrogen and helium.

These collisions emit light. Auroral displays appear in many colours although pale green and pink are common.


Source link

Related Articles

Back to top button