NASA’s Parker Solar Probe has met the sun and lived to tell the tale.
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 December 12 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 looked at this before.”
Parker launched August 12 (SN Online: 8/12/18) and will make 24 close passes by the sun over the next seven years, eventually going to within about 6 million kilometers of the sun’s surface (SN: 7/21/18, p. 12). The spacecraft made its first close flyby November 6, swooping to within roughly 24 million kilometers of the solar surface. That’s about twice as close to the sun as the previous closest spacecraft, the Helios spacecraft in the 1970s. At peak speed, Parker was racing at about 375,000 kilometers per hour, roughly twice Helios’ speed.
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 (SN Online: 8/20/17).
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 downlinked 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.”
Editor’s Note: This story was updated on December 19, 2018, to correct that the bright dot in the image is Mercury, not Jupiter.