Launched on August 12th, 2018, the Parker Solar Probe will make the closest approach to the Sun in history. Over a time period of roughly seven years, PSP will use Venus for gravitational assist to make successively closer approaches to the Sun at distances as small as 4 million miles from the sun’s surface. PSP needs to get this close to breach the corona, or the Sun’s atmosphere. There are a handful of puzzling aspects about the corona, including how energy moves about the corona and how solar wind is accelerated.
One important discovery made this past December was the switchback, a reversal in the direction of the Sun’s magnetic field. During a switchback, a magnetic field radiating away from the Sun is bent back around and points back towards it. The origins of these switchbacks is still unknown, but they offer an explanation for how solar wind can be accelerated and why there are relatively large waves of solar wind at times.
Another area of research that PSP is gathering data for is the path that solar wind takes throughout its “lifetime”. The Sun is rotating, and so is the solar wind around it. However, when the solar wind reaches Earth, it appears to be moving radially away from the Sun. Finding the point where the solar wind is freed from its centripetal motion will provide insight on how the Sun spends its energy throughout its life, and such developments could allow heliophysicists to study other distant stars and their life cycles.
The future is very bright for heliophysics; PSP is continually surprising scientists with its discoveries, and if the data keeps coming in like it is now, PSP will have been significantly more productive than was anticipated.