Scientists say the sun is ‘waking up’ — what this means and the possible effects
Scientists say we are in the middle of a period of heightened solar activity that could increase the number of phenomena such as flares, coronal mass ejections and geomagnetic storms.
A large hole capable of generating solar winds north of a million miles per hour has appeared on the surface of the sun for the second time in a week.
Here’s what you need to know about the sun ‘waking up’.
What is a coronal hole?
Coronal holes are a normal occurrence and a relatively common feature of the sun’s outer atmosphere, called the corona.
The large coronal hole on the sun’s surface spotted this week is 20 times bigger than Earth.
Nasa’s Solar Dynamics Observatory spotted it, and it could send superfast solar winds of 1.8 million miles per hour hurtling towards our planet today (Thursday, March 30).
Daniel Verscharen, associate professor of space and climate physics at University College London, told Sky News: “This one is special because it is near the sun’s equator.
“Since the sun rotates, an equatorial coronal hole can point towards the Earth at some point.”
This week’s coronal hole is not expected to cause damage. However, scientists say the heightened activity is something we might need to be wary of.
Why is there increased solar activity?
Professor Verscharen said the sun was “waking up”.
The increased solar activity recently is a sign of a more active sun, and a period known as solar maximums.
These occur every 11 years or so, prompting several holes and more significant phenomena such as coronal mass ejections (CMEs).
Prof Verscharen said: “Equatorial coronal holes, coronal mass ejections, and thus also aurorae are going to be more likely in the coming years.”
It means the amount of radiation emitted by the sun can be dangerous for astronauts going beyond the protection of Earth’s ionosphere. This is where the planet’s atmosphere meets space.
The main concern surrounding increased solar activity relates to satellites.
Geomagnetic storms can impact satellite communications, which could become more disruptive as humans become ever more reliant on them.
A solar storm in January 2021 prompted Atlanta-based airline Delta to alter the course of some flights between Detroit and Asia.
The largest such storm on record was the Carrington Event. This hit Earth in 1859 and prompted the telegraph systems across America and Europe to fail.
What impact can solar winds have?
Solar winds are a flow of plasma launched at super-fast speeds — 700 or 800 kilometres (435 or 497 miles) per second.
When these winds collide with the Earth’s charged atmosphere, this can result in magnificently bright auroras, such as the Northern Lights.
These are a lot more aesthetically pleasing than coronal holes. The US’s National Oceanic and Atmospheric Administration, which monitors space weather, says they appear so dark that they are relatively cool and less dense than surrounding areas of the sun.