New research may help scientists unravel the physics of the solar wind

Mon, 17 Jan 2022 20:10:19 GMT
Space Daily

Minneapolis MN (SPX) Jan 18, 2022 A new study led by University of Minnesota Twin Cities...

A new study led by University of Minnesota Twin Cities researchers, using data from NASA's Parker Solar Probe, provides insight into what generates and accelerates the solar wind, a stream of charged particles released from the sun's corona.

Understanding how the solar wind works can help scientists predict "Space weather," or the response to solar activity-such as solar flares-that can impact both astronauts in space and much of the technology people on Earth depend on.

The scientists used data gathered from Parker Solar Probe, which launched in 2018 with the goal to help scientists understand what heats the Sun's corona and generates the solar wind.

Previous research has indicated that in the solar wind, at distances from about 35 solar radii out to the Earth's orbit at about 215 solar radii, electromagnetic waves called "Whistler" waves help regulate the heat flux, one form of energy flow.

In this new study, the University of Minnesota-led research team discovered that in a region closer to the sun, inside around 28 solar radii, there are no whistler waves.

"What we found is that when we get inside 28 solar radii, we lose the whistlers. That means the whistlers can't be doing anything to control the heat flux in that region," said Cynthia Cattell, lead author on the paper and a professor in the School of Physics and Astronomy at the University of Minnesota Twin Cities.

Learning about the solar wind is also important to scientists for other reasons.

The energetic particles that propagate through the solar wind can also be harmful to astronauts traveling in space.

"And if you don't understand the details of energy flow close to the sun, then you can't predict how fast the solar wind will be moving or what its density will be when it reaches Earth. These are some of the properties that determine how solar activity affects us."

Research Report: "Parker Solar Probe evidence for the absence of whistlers close to the Sun to scatter strahl and to regulate heat flux".