NASA’s Parker Solar Probe has kissed the outer corona of the Sun and lived to tell the tale.
Just weeks after making the closest ever flyby of the Sun, NASA's Parker Solar Probe has begun sending back it's data.
The sun-grazing spacecraft has already broken the records for the fastest space probe and the nearest brush any spacecraft has made with the sun. Now the probe is sending data back from its close solar encounter, scientists reported this week at the American Geophysical Union meeting in Washington, D.C.
“What we are looking at now is completely brand new,” solar physicist Nour Raouafi of Johns Hopkins University Applied Physics Lab in Laurel, Md., said at a news conference. “Nobody has looked at this before.”
Parker launched August 12 and will make 24 close passes by the sun over the next seven years, eventually going to within about 6 million kilometres of the sun’s surface.
The spacecraft made its first close flyby November 6, swooping to within roughly 24 million kilometres of the solar surface. That’s about twice as close to the sun as the previous closest spacecraft, the Helios spacecraft in the 1970's. At peak speed, Parker was racing at about 375,000 kilometres per hour, roughly twice Helios’ speed.
Above is what is called a streamer, a dense part of the corona, moves away from the Sun (out of view to the left)
Parker's WISPR instrument acquired the vista just 27.2 million km from the surface of the Sun on 8 November. The bright dot is actually far-distant Jupiter. The black dots are repeats that occur simply because of the way the picture is constructed.
This region is strangely hotter than the star's "surface", or photosphere. While this can be 6,000 degrees Celsius, the outer atmosphere may reach temperatures of a few million degrees.
"We want to understand why there is this temperature inversion, as in - you walk away from a hot star and the atmosphere gets hotter not colder as you would expect."
But because the probe was on the opposite side of the sun from Earth during the flyby, Parker didn’t start relaying its observations until December 7.
After the probe emerged from behind the sun, the Parker team got its first up-close look at the wispy outer solar atmosphere, called the corona. One of the first images from Parker’s camera shows unprecedented detail in a solar streamer, a filament of plasma in the corona. The team hopes that Parker’s data will help solve the mystery of why the corona is about 300 times as hot as the sun’s surface.
Only about one-fifth of the data recorded during Parker’s initial flyby will reach scientists before the sun gets between Earth and the spacecraft again. The rest of the data will be down-linked next year, between March and May. Scientists hope to start publishing results soon after.
“If you ask any scientist in the team or even outside what to expect, I think the answer would be, we don’t really know,” Raouafi said. “We are almost certain we’ll make new discoveries.”
Parker will go quicker still on future close passes of the Sun.
