A massive hole has opened on the Sun, unleashing a high-speed stream of solar wind aimed directly at our planet. And while such solar storms can cause power grid disruptions and dazzling auroras, this one is expected to be harmless.
Astronomers spotted the dark region in the outer reaches of the Sun’s atmosphere, known as the corona. It’s large enough to fit 20 to 30 Earths back-to-back, NASA researchers tell Insider. It looks black because the corona is more excellent than other areas, and the Sun’s magnetic dynamo has weakened the magnetic fields that dominate it.
When a coronal hole forms, it allows bits of plasma to escape from the Sun into space, carrying the Sun’s magnetic field. The resulting solar winds can be fast, reaching 500 to 800 kilometers per second. They aren’t just hot and magnetic but carry the Sun’s energy, making them an essential power source for stars.
The Parker Solar Probe’s observations of the current coronal hole have revealed some intriguing details about its formation. The probe detected streams of high-energy particles that match the characteristics of “interchange reconnection,” a process by which magnetic fields within these funnel-like regions on the surface of the Sun break and reconnect, slinging charged particles into space.
Solar physicists also think these jets can explain why the Sun’s coronal holes are so fast and what keeps them from collapsing. They can be seen in the image above, captured by NASA’s Solar Dynamics Observatory. The picture shows a gaping dark expanse across the Sun’s surface, nearly 800,000 kilometers long. In the image, red and blue regions show the active Sun, with dark corona extending well above the photosphere, the visible layer of our star.
These aren’t the only signs that our closest star is about to unleash a series of blows on Earth. A massive solar flare and several coronal mass ejections have been detected, putting us in for a bumpy ride this week as the Sun enters its peak activity phase of the 11-year solar cycle.
As the Sun’s energy builds up, scientists expect more such flares and coronal holes to form and more solar storms that can disrupt power grids and satellite communications. NASA’s Living With a Star program aims to get a better handle on how the Sun influences our planet and vice versa.
Please support our work and get access to exclusive content! Please pledge to support us on Patreon for as little as $3 per month. Thanks! —This story was originally published on March 25, 2024. It was updated on April 2, 2024, to add new images and explain why this story is still relevant.
