A space probe penetrates the sun’s atmosphere for the first time • Trends21

For the first time in history, an Earth-based space probe has penetrated the mysteries of the sun’s upper atmosphere and flew over our star 13 million kilometers from its surface. Big step for solar energy science.

For the first time in history, a spacecraft touched the Earth’s sun, as announced by NASA in Release: passed through its atmosphere, took samples of particles and analyzed magnetic fields.

The solar atmosphere consists of three layers: the photosphere, the chromosphere, and the solar corona made of plasma. The corona extends more than a million kilometers above the chromosphere and is part of the solar atmosphere that the probe passed through. Parker Solar Probe from NASA.

Parker set out in 2018 on a seven-year mission whose main goal was to circle the outer perimeter of the sun’s corona, and three years after its launch and decades after its first pregnancy, it has finally reached its destination.

The Sun’s atmosphere is made up of solar material associated with gravity and magnetic forces. As increased heat and pressure pull this material away from the Sun, it reaches a point where gravity and magnetic fields are too weak to contain them.

Related topic: For the first time we touch the sun

critical surface

This point, known as the Alfvén critical surface, marks the end of the atmosphere and the beginning of the solar wind, and the outpouring of charged particles ejecting from the corona: this limit is the limit that the Parker Solar Probe crossed.

Although the exact location of the critical Alfvén surface is unknown, estimates place it between 10 and 20 solar radii from the surface of the Sun: between 6.9 and 13.8 million km.

Parker Solar was able to verify that it was crossing this critical surface when it positioned itself 13 million kilometers from the surface of the Sun: it has already entered our star’s atmosphere.

During its flight, Parker Solar Probe was able to verify that Alfvin’s critical surface is not in the shape of a smooth ball. Instead, it has peaks and valleys that wrinkle its surface.

More possibilities for the future

Discovering where these bulges align with solar activity from the surface will help scientists discover how events on the sun affect the atmosphere and the solar wind.

Although this first flight through the corona only lasted a few hours, the Parker mission will continue to get close to the sun: subsequent flights, the first of which will take place in January 2022, will return the Parker Solar Probe to the solar corona.

In addition, as the corona increases in size with the increase in the solar cycle, Parker Solar will have a better chance in the future to spend more time in this part of the atmosphere and obtain more information.

in the eye of the storm

Another discovery: When the Parker Solar Probe descended to just under 15 solar radii (about 10.4 million km) from the surface of the Sun, it passed through a special feature of the solar corona called the false carrier—it was like flying in the eye of a storm.

Inside the pseudo-emitter, conditions calmed, particles slowed, and the number of bends decreased—a radical change from the busy barrage of particles the spacecraft encounters in the solar wind.

For the first time, the spacecraft found itself in an area where magnetic fields were strong enough to control the movement of particles.

This is a big step for solar science, as NASA highlights: Just as the moon landing allowed scientists to understand how our satellite was formed, touching the material the Sun is made of will help scientists discover critical information about our nearest star and its star. Impact on the solar system.

New results from NASA’s Parker Solar Probe were announced Dec. 14 at a news conference at the 2021 American Geophysical Union’s fall meeting in New Orleans. The results were published in Physical Review Letters and accepted for publication in the Astrophysical Journal.

reference

The Parker Solar Probe enters the magnetically dominant solar corona. JC Casper et al. Phys. Reverend Litt. 127, 255101. DOI: https://doi.org/10.1103/PhysRevLett.127.255101

Above image: Illustration of the Parker Solar Probe spacecraft entering the solar atmosphere. / NASA / GSFC