Researchers have discovered a complex, dynamic, network-like plasma structure in the middle atmosphere. indicating that the sun is the solar wind — A steady stream of charged particles emanating from the Sun — is formed within this web. The discovery resulted in rare observations of a difficult region of the Sun, paving the way for a NASA mission due to launch next year.

“We had no idea if it would work or what we would see,” said y. expressions Dan Seaton, a solar physicist at the Southwest Research Institute in Colorado and one of the study’s authors. “The results were very exciting. For the first time, we have high quality observations that fully integrate our solar and heliosphere observations in a single system.” Computer simulation of the middle corona magnetic field. (Images: Nature Astronomy, Chitta et al.)

outer layer solar atmosphere It is called the corona and is usually only visible to humans during total solar eclipses, when the moon blocks most of the sunlight. Located about 650,000 miles (1 million kilometers) above the sun’s surface, the middle corona was the least observed region of the solar atmosphere, in part because there were no observations of the solar corona below 1.3 million miles (2 million km).

Researchers in August 2021 announced about First-of-its-kind observations of the middle corona at extreme ultraviolet wavelengths. Using advanced instruments with expanded fields of view, scientists discovered that solar wind structures originate from the middle corona. This provided the first full understanding of the origin of the solar winds – a glimpse into understanding a key phenomenon that affects every planet in the solar system.

The solar wind is an example of what scientists call it. space weather, a series of ways in which the sun and its glare affect the Earth. Space weather can destroy electronic equipment, weaken radio communications, add interference to cell phone reception, and disable electrical networks. However, scientists do not fully understand the mechanisms that propagate solar winds and other space weather, making these events nearly impossible to predict.

Now, new observations combined with data from additional space probes and computer models have revealed a complex network of plasmas in the middle corona.

An international group of researchers analyzed data from a lunar observing campaign using the Solar Ultraviolet Camera (SUV) on the NOAA weather satellite GOES-17. The satellite’s expanded field of view captured images of not only the Sun’s center but also its sides, providing an unusual insight into the structure and evolution of this region.

“We had a rare opportunity to use the instrument in an unusual way to observe a truly unexplored region,” Seaton said a second later. expression. “We didn’t even know if it would work, but we knew we would make important discoveries if it did.”

Using this data, the team tracked a pair of coronal holes (sunspots) that appear dark as the solar disk orbits, marking where the sun’s magnetic field is open to space and eruption. When coronal holes appeared on the eastern and western edges of the Sun, the researchers discovered that the middle corona was a highly structured coronal network called the “S-mesh”.

This complex network consists of magnetized plasma structures that constantly interact and reconnect. The researchers saw this mechanism in play as it causes the solar wind to flow through the coronal web.

The results of this study could be useful for NASA’s Polarimeter for the Unification of the Corona and Heliosphere (PUNCH) mission, scheduled to launch in 2023. This two-year mission will use 3D imaging to capture the Sun’s outer corona and the region closest to it in the Solar System to better understand how the corona produces the solar wind.

“Now that we can image the central corona of the Sun, we can relate what PUNCH is seeing to its source and have a more complete picture of how the solar wind interacts with the rest of the Solar System,” said Seaton, head of the Center for Science Operations. In the statement, the leader of PUNCH. “Before these observations, very few people believed that the middle corona could be observed at these distances in the UV. These studies launched an entirely new approach to observing the corona on a large scale.”