Astrophotographer captures a half-million-mile long solar prominence

An astrophotographer captured a half million-mile-long plasma plume as it shot out from the surface of the sun. The plume is known as a coronal mass ejection and was part of a minor solar storm. The image was created by capturing hundreds of thousands of images over several hours using a specially modified telescope.

The image was captured on September 24 by astrophotographer and Arizona resident Andrew McCarthy. His images are well known for their extraterrestrial beauty and fine attention to detail. But something about this image was different.

“Today the sun produced the largest coronal mass ejection I’ve ever witnessed,” McCarthy wrote on the subReddit r/space. “What you’re seeing here is the sun’s ‘chromosphere’ in Hydrogen-Alpha light,” he explains.

“This reveals the feathery spicules (plasma jets), filaments, and prominences. One such prominence (the long thing seen on the left side), snapped off, ejecting matter deep into space.”

He goes on to explain how he followed the plume and was astounded at how far it reached out into space. “I tracked it nearly a million miles out into space and will share a timelapse as soon as I’m done stabilizing the footage. This composite image shows how far the prominence reached before it snapped, far larger than any I’ve seen before,” he adds. Although McCarthy tracked the ejection to around a million miles, the one in the image is actually half of that length.

To create the image McCarthy stacked hundreds of thousands of images taken over a six-hour time frame. Between 30 and 80 images were captured every second. They were then stacked together to create the image above.

The colours, however, are actually more of an artist’s impression than reality. The chromosphere (the lowest region of the sun’s atmosphere) and CMEs naturally give off a type of light that looks pinkish-red to us and is known as hydrogen-alpha, or H-alpha, light. But because the exposure time of each image was so short, the original images were almost completely white.

McCarthy added the orange hues while compositing the final image, to create a more natural-looking impression of what our brains think of as sun colour.

These plasma plumes are becoming more frequent and more powerful as the sun is entering a new activity phase known as the solar maximum, which lasts around seven years. Solar storms are also responsible for the increased visibility of the auroras or Northern lights as they are known.

“We’ll see more of these as we head further into solar maximum,” McCarthy wrote. The plasma plumes are also likely to get “progressively larger,” he added. That means there will be plenty of opportunities for more images like this one to be captured.

However, McCarthy has some sage advice for anyone wanting to try this. “DO NOT point a telescope at the sun,” he says, “you’ll fry your camera or worse, your eyes. My telescope was specially modified with multiple filters for this.”

You can follow Andrew on Instagram or see his work on his website.