#NASA; #Washington; #Switchbacks; NASA'sParkerSolarProbe
Washington, Dec 4 (Canadian-Media): New revelations of Sun in dramatic detail, by NASA's Parker Solar Probe, sheds light on the formation of other stars and their behaviour in the universe, NASA reports said.
The WISPR image on NASA's Parker Solar Probe captured imagery of the constant outflow of material from the Sun during its close approach to the Sun in April 2019. Image Credits: NASA/NRL/APL
Scorching temperatures are being endured by the spacecraft to gather data being shared for the first time, details of which are given in four new papers -- now available online from the journal Nature -- throwing light on previously unknown and only-theorized characteristics of our volatile celestial neighbor.
The information uncovered by Parker about the Sun constantly ejecting material and energy will not only help scientists rewrite the models and render a better understanding of the creation and evolution of the stars, but also protect astronauts and technology in space, an important part of NASA’s Artemis program, which will send the first woman and the next man to the Moon by 2024 and, eventually, on to Mars.
Through these flybys, the mission also has examined the dust of the coronal environment, and spotted particle acceleration events so small that they are undetectable from Earth, which is nearly 93 million miles from the Sun.
For the first time, scientists are able to study the solar wind from its source, the Sun's corona, similar to how one might observe the stream that serves as the source of a river. This provides a much different perspective as compared to studying the solar wind were its flow impacts Earth.
One particular event which caught the attention of the science teams was flips in the direction of the magnetic field. These reversals – dubbed "switchbacks" – appear to be a very common phenomenon in the solar wind flow inside the orbit of Mercury, and last anywhere from a few seconds to several minutes as they flow over the spacecraft.
Mechanisms of heat and accelerate the solar wind are more clear by these switchbacks. They not only provide understanding of what causes the solar wind and space weather affecting Earth, but also helps us understand a fundamental process of how stars work and how they release magnetic energy into their environment.
NASA's Parker Solar Probe observed a slow solar wind flowing out from the small coronal hole – the long, thin black spot seen on the left side of the Sun in this image captured by NASA's Solar Dynamics Observatory – on October 27, 2018. While scientists have long known that fast solar wind streams flow from coronal holes near the poles, they have not yet conclusively identified the source of the Sun's slow solar wind. Image credits: NASA/SDO
Some surprising clues have been found by researchers as to how the Sun’s rotation affects the outflow of the solar wind, which can be accessed in a separate publication, based on measurements by the Solar Wind Electrons Alphas and Protons (SWEAP) instrument.
As Parker ventured to a distance of around 20 million miles from the Sun, researchers obtained their first observations of this effect which is key to helping us understand how the Sun’s rotation slows down over time, as well as other stars and the formation of protoplanetary disks, dense disks of gas and dust encircling young stars.
Dust in the Wind
First direct evidence of dust starting to thin out around 7 million miles from the Sun was also observed by Parker using Parker’s Wide-field Imager for Solar Probe (WISPR) instrument, at a distance of about 4 million miles from the Sun, that has been impossible to measure until now. The spacecraft hopes observe as early as September 2020, during its sixth flyby a truly dust-free zone beginning at a distance of about 2-3 million miles from the Sun, which would signal a place where the material of the dust has been evaporated by the Sun’s heat, to become part of the solar wind flying past Earth.
Finally, several never-before-seen events so small that all traces of them are lost before they reach Earth had been measured by Parker's Integrated Science Investigation of the Sun (ISʘIS) energetic particle instruments. Solar energetic particle events are important, as they can arise suddenly and lead to space weather conditions near Earth that can be potentially harmful to astronauts. Unraveling the sources, acceleration and transport of solar energetic particles will help us better protect humans in space in the future.
“The Sun is the only star we can examine this closely,” said Nicola Fox, director of the Heliophysics Division at NASA Headquarters. “Getting data at the source already is revolutionizing our understanding of our own star and stars across the universe. Our little spacecraft is soldiering through brutal conditions to send home startling and exciting revelations.”