Taking a page out of Emeril Lagasse’s cookbook NASA has kicked exploration of the solar system up another notch. This time, the space agency says its Parker Solar Probe—a space probe NASA launched in 2018—has “touched the Sun,” and even sampled local particles and magnetic fields. All we can say is: Somewhere, Icarus must be proud. Or green with envy.
DesignTAXI reported on the seminal star touch, which NASA refers to as a “giant leap” for solar science. Just as landing astronauts and rovers on the Moon has allowed scientists to better understand the celestial body’s origins, NASA says “touching” the Sun will better illuminate the mysteries of our home star and how it influences its surroundings in space.
NASA notes that the Sun, unlike Earth, has no solid surface; instead, the ball of hot plasma has a superheated atmosphere. One consisting of solar material the Sun keeps bound to it via gravity and magnetic forces. On April 28 of this year, during its eighth flyby of the Sun, NASA’s solar probe encountered “the specific magnetic and particle conditions” to signal it had entered the Sun’s atmosphere. Doing so at a distance of 18.8 solar radii. Or about 8.1 million miles from the Sun’s outer shell.
“We were fully expecting that, sooner or later, we would encounter the corona [or the Sun’s upper atmosphere] for at least a short duration of time,” Justin Kasper, lead author of a new paper outlining the milestone published in Physical Review Letters, said in a NASA press release. “But it is very exciting that we’ve already reached it,” the professor of climate and space sciences added.
NASA says that Parker’s contact with the Sun’s corona has allowed them to glean where the Alfvén critical surface lay. The Alfvén critical surface, the space agency notes, marks the end of the solar atmosphere and beginning of the solar wind—that is, the outflow of charged particles emanating from the Sun’s corona. Until now, researchers were unsure exactly where the Alfvén critical surface began.
Along with better defining the boundary of the Alfvén critical surface, this latest flyby allowed the Parker Solar Probe to further analyze magnetic zig-zag structures in the solar wind. The structures, which scientists refer to as “switchbacks,” are plentiful close to the Sun. But now scientists have connected the switchbacks to funnel-shaped magnetic fields that emerge from the Sun’s outer shell, or photosphere. Project scientists believe the magnetic funnels may also be the origin of cosmic wind. Although it seems NASA will have to send Parker even closer to the Sun in the future to confirm that hypothesis.
