Parker Solar Probe’s New Discoveries
Dec. 4, 2019 (EIRNS)—The Parker Solar Probe (PSP) mission team presented exciting new discoveries today that the Probe has made, in its mission to “touch the Sun.” This was via a media teleconference, with additional articles and documentation to follow in coming days. The PSP is on a nearly seven-year mission, and has completed nearly 3 of its 24 planned orbits. This is the first such conference held by NASA to discuss these findings of this mission so far.
The discoveries include:
• New dynamics of the solar wind: As seen from Earth, the solar wind appears to be a somewhat smooth, steady stream of charged particles and magnetic fields, with occasional turbulence. However, what the PSP found is that the stream of particles sometimes makes quick reversals in the magnetic fields, and then suddenly releases faster-moving jets of particles, making the solar wind close to the Sun extremely turbulent. These reversals—rapid flips in the magnetic field, such that it makes an almost 180° rotation in a whip-like motion, have been dubbed “switchbacks.” Waves in the solar wind have been observed for decades, but the mission scientists were surprised that “we were not expecting to see them organize into these coherent structured velocity spikes,” in the words of one investigator.
• The solar wind rotates: Again, from our vantage point on Earth, the solar wind appears to emanate in straight lines out from the Sun. Although it’s been known for a long time that the corona rotates with the Sun, the PSP was able to detect the point at which the solar wind transitions from rotational action to begin streaming out radially; this transition point happens significantly farther out than expected. The Probe was able to orbit within the corona, and the strength of its circulation was greater than any scientist predicted.
• A dust-free zone: Cosmic dust is pervasive throughout the universe, but mission investigators had predicted a dust-free zone near the Sun. For the first time in history, this zone was imaged by the instruments on the PSP. This dust cloud begins to thin at around 7 million miles from the Sun, and is expected to disappear altogether at around 4 million miles. The dust is vaporized and dispersed by the Sun’s heat; the PSP will dip to less than 4 million miles from the surface of the Sun in one of its last scheduled orbits.
• Mini-solar flares: In addition to the huge flares shot out from the Sun, the PSP was able to detect many “mini-flares” of high-energy charged particles. These are so small, that they disperse long before reaching Earth; this is the first time they’ve been observed.
Understanding the Sun and its dynamics are crucial for protecting astronauts in space, understanding how these dynamics affect Earth weather, and how to better protect our infrastructure. The PSP can be expected to reveal more startling discoveries as the mission progresses.