The Daniel K. Inouye Solar Telescope (DKIST) has captured some of the most remarkable sun photos I’ve ever seen. They bring us close to the sun without melting our wings, giving us a glimpse of its turbulent, scorching surface – and even the rarely seen decaying sunspots.
DKIST is located atop a mountain on the island of Maui, Hawaiian, and it’s the world’s largest solar telescope. Like all these giant telescopes, it’s made to help astronomers learn more about the Sun, its surface, activity, and atmosphere. It’s been collecting high-resolution data over the past year, and now we’ve been presented with some of its findings.
A particularly interesting feature captured in some of these photos is sunspots. These regions have a magnetic field 2,500 times stronger than Earth’s. This causes a decrease in temperature due to increased magnetic pressure and decreased atmospheric pressure. The magnetic field also restricts the flow of hot gas from the Sun’s interior, leading to this phenomenon.
Sunspots are dark regions on the Sun’s surface, commonly found in pairs with opposite magnetic fields. They consist of an umbra (a dark area), and a penumbra(a lighter region). Sunspots appear dark because they are cooler than the surrounding photosphere, which is about 6,300 degrees F. They are usually huge, with an average size the same as the Earth or bigger.
Even though the sunspots are so powerful, they last very short: for roughly a week. Their number grows and they shrink as the sun progresses through its 11-year activity cycle.
For starters, here’s the first image of the chromosphere taken with the DKIST on June 3, 2022. Chronosphere is the area of the Sun’s atmosphere above the surface, and in this image, you’re seeing a region 82,500 kilometers across at a resolution of 18 km.
Here’s the same image with the Earth for scale.
These are solar sunspots captured by the DKIST captured on May 11, 2021. “The data leading to this image were acquired with the Visible Broadband Imager blue channel at a wavelength of 450 nanometers,” NSO explains.
This image, which reminds me a bit of the Eye of Sauron, is the first sunspot image taken by the NSF’s Inouye Solar Wave Front Correction (WFC) context viewer camera on January 28, 2020.
“[It] shows a slice through the three-dimensional structure of the sunspot. The sunspot is sculpted by a convergence of intense magnetic fields and hot gas boiling up from below. This image uses a warm palette of red and orange, but the Inouye Solar Telescope’s Wide Field Camera context viewer took this sunspot image at the wavelength of 530 nanometers (in the greenish-yellow part of the visible spectrum). This is not the same naked eye sunspot group visible on the Sun in late November and early December 2020.”
This is the highest-resolution image of the Sun’s surface ever taken. The DKIT took this picture at 789nm, showing us features as small as 30km (18 miles) in size for the first time ever.
“The image shows a pattern of turbulent, “boiling” gas that covers the entire sun. The cell-like structures – each about the size of Texas – are the signature of violent motions that transport heat from the inside of the sun to its surface. Hot solar material (plasma) rises in the bright centers of “cells,” cools off and then sinks below the surface in dark lanes in a process known as convection. In these dark lanes we can also see the tiny, bright markers of magnetic fields. Never before seen to this clarity, these bright specks are thought to channel energy up into the outer layers of the solar atmosphere called the corona. These bright spots may be at the core of why the solar corona is more than a million degrees!”
And here it is even closer up, with the US state of Texas for scale: