They observe cobwebs of plasma in the middle corona of the Sun

Dec. 21 () –

Astronomers have discovered cobweb-like plasmatic structures in the mid-corona of the Sun, with the ultraviolet (UV) wavelength imaging method of the median corona.

In a new study published in Nature Astronomy, the authors — from the Southwest Research Institute (SwRI), NASA, and the Max Planck Institute for Solar System Research (MPS) — say their findings could help to better understand the origins of the solar wind and its interactions with the rest of the solar system.

Since 1995, NOAA has observed the solar corona with the Wide Angle and Spectrometric Coronagraph (LASCO) installed aboard NASA and ESA Solar and Heliospheric Observatory (SOHO) spacecraft to monitor space weather that could affect to the earth. But LASCO has a gap in observations that obscures our view of the mid-solar corona, where the solar wind originates.

“Since the 1950s we have known the outflow of the solar wind. As the solar wind evolves, it can drive space weather and affect things like power grids, satellites, and astronauts“, says the doctor Dan Seaton, principal scientist of the SwRI and one of the authors of the study. “The origins of the solar wind and its structure remain a mystery. Although we have a basic understanding of the processes, we haven’t had observations like these before, so we had to work with an information gap.”

To find new ways to observe the Sun’s corona, Seaton suggested pointing a different instrument, the Solar Ultraviolet Imager (SUVI) on NOAA’s Geostationary Operational Environmental Satellites (GOES), on either side of the Sun instead of directly at it and perform UV observations for a month. What Seaton and his colleagues observed were elongated, web-like plasma structures in the Sun’s central corona. Interactions within these structures release stored magnetic energy that propels particles into space.

“No one had observed what the solar corona was doing in UV at this altitude for so long. We had no idea if it would work or what we would see,” he explains. it’s a statement. “The results were very exciting. For the first time, we have high-quality observations that completely unite our observations of the Sun and the heliosphere as a single system.”

Seaton believes these observations could lead to a more complete picture and even more exciting discoveries from missions like PUNCH (Polarimeter to Unify the Corona and Heliosphere), a NASA mission led by SwRI that will take images of how the outer corona of the Sun becomes the solar wind.

“Now that we can image the Sun’s central corona, we can connect what PUNCH sees with its origins and get a more complete picture of how the solar wind interacts with the rest of the solar system,” Seaton said. “Before these observations, very few people believed that the mid-corona could be observed at these distances in UV. These studies have opened up a whole new approach to observing the corona on a large scale.”