The closest ever mission to the Sun has discovered dynamic structures in the solar wind that will help explain how this flux of charged particles is created and evolves as it travels out into space. The results are highly relevant here on Earth because the solar wind generates space weather including solar storms, which can damage power grids, communication networks and satellites.
NASA’s Parker Solar Probe launched in 2018 and has made measurements of the Sun from a distance of just 24 million km. This is less than half the distance between Mercury and the Sun.
The first results from the mission show bizarre S-shaped bends in the solar wind, which is a stream of energetic charged particles riding through the Solar System on magnetic field lines emanating from the Sun. There are two main components to the solar wind: the fast wind that appears to emanate from magnetic gaps in the Sun’s corona; and the slow wind, which is more of a puzzle.
Indeed, understanding how the particles in the solar wind are accelerated, and what role the heating of the corona (the Sun’s the million-degree-hot atmosphere) has in this, is the greatest mystery facing solar physicists.