For many people, catching a glimpse of the northern lights at the north and south poles is a bucket list, once-in-a-lifetime, moment. Well, prepare to tick that item off your list: the auroras could be visible in skies across the US and UK tonight.
Yesterday, the NOAA (National Oceanic and Atmospheric Administration) Space Weather Prediction Center issued a geomagnetic storm warning, following eruptions on the Sun’s surface that are sending a stream of aurora-causing particles our way.
What time can I see the northern lights?
Scientists expect the auroras to be visible tonight (25 March) and into the early hours of tomorrow (26 March). They will be most visible between 11pm and 12am.
“To predict exactly where you can see the northern lights is difficult as conditions can change quickly,” says Prof Don Pollacco from the University of Warwick’s physics department.
“However, one thing is for sure, and that is that you are unlikely to see them from a brightly lit city environment – you need to go somewhere dark and look towards the northern horizon (look for the North Star). So, you would preferably be in the countryside away from street lights.”
The best time for viewing is typically during the darkest hours of the night, from around 11:00pm – 12:00am. But as Pollacco said, it’s difficult to predict exactly when they’ll crop up, so it could be a late night for any ardent aurora hunters.
The further north you are in the Northern Hemisphere, the better your odds are of seeing the spectacle. The same is true in the Southern Hemisphere for observers further south.
According to astrophysicist Dr. Paul Strøm, “The best way to see an aurora is to sign up to an alert service which may provide the most current activity status.” For those in the UK, he recommends AuroraWatch UK.
Suppose you want to capture an image of the spectacle. In that case, Strøm advises “a long exposure image of a few seconds taken with the sensitivity of the camera turned up (higher ISO) on a tripod (or put on something else which keeps the camera still).”
Where can I see the northern lights?
In the Northern Hemisphere, the aurora borealis – the northern lights – could be visible across the US in states like Washington, Wisconsin and New York; possibly even as far south as Northern California and Alabama if the current strength of the geomagnetic storm holds.
In the UK, Scotland and Northern Ireland could be in for a treat if the skies remain clear.
Meanwhile, in the Southern Hemisphere, Australia’s Bureau of Meteorology’s space weather forecasting centre put out an aurora alert for aurora australis – the southern lights – which could be visible across Tasmania, along the coast in Victoria and on Western Australia’s south-west coast.
Typically, auroras are visible near the magnetic poles of the Earth, which are roughly where the geographic poles are. If you’re in or near the Arctic or Antarctic circles you can expect spectacular light shows too.
Read more:
- What’s the furthest south the Northern Lights have been seen?
- Solar storms have dramatically increased this year. Should we be worried?
- Earth's magnetic field: Should we be worried about the poles flipping?
What causes the northern lights?
Thanks to its molten iron core, the Earth has a powerful magnetic field which interacts with particles ejected from the Sun to cause auroras.
“Auroras are caused when huge magnetic bubbles of gas are ejected into space by the Sun,” Dr Darren Baskill, astronomer lecturer at the University of Sussex, tells BBC Science Focus.
“Occasionally, these bubbles collide with the Earth causing the Earth’s magnetic field to channel gas towards the north and south poles, causing the sky to glow with the shimmering lights of the aurora.”
Baskill explains that the Sun has an 11-year cycle, where its magnetic field periodically gets stronger and weaker. Right now we’re heading towards the peak of this cycle, which means we can expect a lot more aurora over the next year or so as the Sun becomes increasingly active.
Tonight’s light show follows “an energetic solar flare emitted a bubble of gas (known as a coronal mass ejection) early on Sunday 24 March 2024,” Baskill says. “Since the gas from the Sun (the solar wind) is currently travelling at about 800 km/s, we expect that gas to hit the Earth sometime on Monday night into Tuesday morning.”
Why are auroras different colours?
The colours of the aurora borealis and australis are determined by the specific atoms in Earth’s atmosphere engaging with solar particles.
When oxygen atoms situated at higher altitudes react, they produce a green aurora. However, blue, yellow or red sightings indicate interactions between solar particles and oxygen or nitrogen atoms at lower altitudes.
The purple colour that's sometimes seen results from interactions with hydrogen and helium.
Could the geomagnetic storm be dangerous?
Don’t worry, there’s no need for you to be concerned about the geomagnetic storm, other than if you’re trying to see the auroras.
That said, the storm could interfere with some high-frequency radio transmissions. Experts will be watching aircraft and satellite communications carefully to make sure everything continues running smoothly.
In a statement on Sunday, the NOAA Space Weather Prediction Center said: “The public should not anticipate adverse impacts and no action is necessary,” adding that, “infrastructure operators have been notified to take action to mitigate any possible impacts.”
The statement did warn, however, that there was the possibility of more frequent and longer periods of interruptions to GPS systems.
About our experts
Don Pollacco is a professor in the astronomy and astrophysics group at the University of Warwick. His primary research interest is extrasolar planets, and he was responsible for the SuperWASP project in La Palma, which, along with its sister facility at SAAO, has become the most successful ground-based planet detection experiment.
Dr Paul Strøm is an assistant professor in the astronomy and astrophysics group at the University of Warwick working on the PLATO space mission. He also works on various astrophysical topics mainly focused on far-UV observations aimed at understanding the formation environments of young planets.
Dr Darren Baskill is an outreach officer and lecturer in the Department of Physics and Astronomy at the University of Sussex. He previously lectured at the Royal Observatory Greenwich, where he also initiated the annual Astronomy Photographer of the Year competition.
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