These incredibly detailed images of the sun were captured by astrophotographer Mark Johnston from his backyard in Scottsdale, Arizona.
As we approach solar maximum, the peak of solar activity during the sun's approximately 11-year solar cycle, the sun has been anything but quiet. Spawning huge sunspots, unleashing powerful solar flares and coronal mass ejections (CMEs) and triggering impressive widespread aurora displays, the sun has certainly been keeping us on our toes.
It's no wonder astrophotographers like Johnston are turning their attention to our home star, because you never quite know what you're going to see with its turbulent nature.
"I like imaging the sun because it's the only object in astronomy that is different every time you look at it," Johnston told Space.com in an email.
Related: The sun's magnetic field is about to flip. Here's what to expect.
Johnstone captured the following images on July 2, showing the highly detailed chromosphere with erupting solar prominences and filaments.
"The richness in detail is fascinating: solar prominences, active regions, sunspots, filament and spicules all change from day to day," Johnston continued.
In the first close-up image, you can see a prominent pair of sunspots alongside glowing arcs of plasma known as filaments that have lifted off from the surface.
"The large dark square 'canopy' of plasma at the bottom right of center is large enough to cover 25 Earths," Johnston said.
In the second image, you can see a line of solar prominences appearing to march across the surface of the sun.
"On the surface, small feathery spicules come and go in only a few minutes," Johnston said. These spicules have a grass-like abundance, giving the solar surface a rather 'fuzzy' appearance. Spicules can reach lengths of 6,000 miles (9,600 kilometers) before collapsing, they erupt jets of solar material as fast as 60 miles (96 km) per second according to NASA.
In Johnston's third image a huge prominence arches across the sun. A solar prominence is also known as a filament when viewed against the solar disk (as seen in the first image), they are anchored to the sun's photosphere and extends out towards the corona — the sun's outer atmosphere. The looping material we see is plasma, a hot gas composed of electrically charged hydrogen and helium, according to NASA.
"On the right millions of tons of plasma have detached from the Sun and float above the surface," Johnston points out.
Johnston used a 160mm hydrogen alpha-modified refractor telescope and a high-speed monochrome camera to capture 2000 10 millisecond frames for each image. Then, in post-production, the best 200 frames from each scene were stacked to create a single image. Further enhancements and sharpening techniques were then applied.
Mark Johnston is a NASA Solar System Ambassador and Vice President of the Phoenix Astronomical Society. You can find him on social media @azastroguy
