Washington: Troves new data from a Nasa probe’s close encounters with the sun are giving scientists unique insight about the solar wind and space weather more generally as the spacecraft zooms through the outermost part of the star’s atmosphere.
Researchers on Wednesday described the first published findings from the Parker Solar Probe, a spacecraft launched in 2018 to journey closer to the sun. The findings, offering fresh details about how the sun spawns space weather, are reshaping astronomer’s understanding of violent solar wind that can hamper satellites and electronics on Earth.
“We were certainly hoping we’d see new phenomena and new processes when we got close to the sun-and we certainly did, ” Nicola Fox, director of the US space agency’s heliophysics division, said.
Earth is roughly 93 million miles from the sun. The probe ventured as close as 24 million km to the sun to gather the data used in the studies published in ‘Nature’. The probe eventually will travel within about 6 million km from the sun’s surface, seven times closer than any previous spacecraft.
The probe has endured extreme heat while flying through the outer most part of the sun’s atmosphere, called the solar coronia, that gives rise to solar corona, that gives rise to the solar wind – the hot energized changed particles that stream outward from the Sun and fill the solar system.
Oscillations in the speed of these charged particles beaming outward from the solar corona have previously been thought to dissipate gradually, much like the waves seen after plucking a guitar string fading from the middle.
One of the probe’s “really big surprises.” according to one of the researchers, was the detections of sudden abrupt spikes in the speed of the solar wind that was so violent that the magnetic field flips itself around, a phenomenon called “swithchbacks”
“ We’re finding these powerful waves that wash over the spacecraft, kind of like rogue waves in an ocean,” said Justin Kasper, an investigator. “They carry a tremendous amount of energy.”