NASA is naming its upcoming mission to “touch the Sun” after Eugene Parker, a prominent astrophysicist who discovered the existence of solar wind — the charged particles that are constantly streaming from our star. The mission, originally named Solar Probe Plus, will now be called the Parker Solar Probe. It’s the first time NASA has named one of its missions after a scientist who is still alive. Parker discovered solar wind in the 1950s and is about to celebrate his 90th birthday.
The Parker Solar Probe is NASA’s plan to send a spacecraft closer to our Sun than ever before. The probe, which is being developed by Johns Hopkins Applied Physics Laboratory, is supposed to launch on top of a Delta IV Heavy rocket in either July or August of 2018 and then spend seven years getting into closer and closer orbits around the Sun. To do this, the vehicle will do seven flybys of Venus, which will eventually bring the spacecraft within 3.7 million miles of the Sun. That’s about eight times closer than any other spacecraft has been before, according to NASA.
From this distance, the Parker Solar Probe will analyze the Sun’s atmosphere, mainly to figure out the mechanics of the solar wind that Parker discovered. The Sun is constantly spewing out highly charged particles in the form of plasma — what is known as solar wind. And it’s all thanks to the Sun’s outer atmosphere, or the corona. Even though the corona extends millions of miles out into space, it is unbelievably hot — so hot that it heats up particles to such extreme temperatures that they break free of the Sun’s gravity and accelerate outward in all directions. This solar wind, which carries part of the Sun’s magnetic field, travels all the way to Earth and slams into our planet’s own magnetic field.
Fortunately, our field acts like a protective barrier, so usually this process is pretty harmless for us. But every now and then, the Sun burps out an extra helping of charged particles known as a coronal mass ejection. When this mess of particles reaches Earth, it can disturb our magnetic field enough to cause geomagnetic storms. These storms aren’t too serious, but they can mess with our power grids and communications systems, as well as damage our satellites.
We know the basics of how solar wind works, but the processes behind these particle bursts are still not totally understood. That’s what the Parker Solar Probe is going to help us figure out. The spacecraft is designed to “trace the flow of energy” that’s responsible for heating up the corona and accelerating the solar wind. And the more we know about how these processes work, the better we can get at predicting when they will happen.
Normally, NASA waits to rename its missions after launch, but the space agency decided to break protocol this time since Parker’s work has been so instrumental for the spacecraft’s mission. His discovery of solar wind has essentially changed our understanding of stars and how they interact with the space around them. Apart from getting the mission named after him, a chip with pictures of Parker will also be included on the vehicles, as well as a copy of his original paper on solar wind.