NASA’s future looks bright. Literally.
The space agency announced Wednesday it intends to fly a probe directly into our sun’s atmosphere, launching sometime in summer 2018.
With an orbit of within four million miles of the sun’s surface, the “Parker Solar Probe” ― named in honor of Dr. Eugene Parker, the University of Chicago professor who successfully predicted the existence of solar wind in 1958 ― the probe will give scientists a closer look at how stars work than ever before.
Mercury, the planet closest to the sun, orbits the star from a distance of about 36 million miles. At that range, the sunlit face of the planet reaches a maximum temperature of 801 degrees Fahrenheit.
By comparison, at four million miles, the Parker Solar Probe will have to endure temperatures of around 2,550 degrees Fahrenheit, a feat achievable thanks to a 4.5-inch-thick, 8-foot-wide carbon composite shield that will protect the probe’s four main instrument groups and keep them operating at room temperature.
High energy supersonic solar radiation will also play a factor, with NASA building the probe to withstand solar intensity “of about 475 times what spacecraft experience while orbiting Earth.”
In Wednesday’s briefing, Nicola Fox, mission project scientist at the Johns Hopkins University Applied Physics Laboratory, called the probe “the coolest, hottest mission under the sun.”
Unlike many planetary exploration missions, which primarily orbit the planet itself, the Parker probe will edge closer and closer to the sun by way of an elliptical orbit that includes Venus, getting a gravity assist from the planet on each of its seven flybys:
While scientists can conduct plenty of solar research at a distance, the most pressing questions require a closer look.
“Until you actually go there and touch the sun you really can’t answer these questions,” said Fox. “You can [only] learn so much from looking out the window.”
NASA has long wanted to send a probe to the sun’s corona, but the technology to do so has only recently been developed.
“Why has it taken us 60 years do to it?” Fox asked in today’s briefing, “Because, honestly, the materials didn’t exist that allowed us to do it.”
Researchers began to iron out the finer details of the solar probe in 2010, including what, exactly, they’d hope to discover with the mission.
“The experiments selected for [Solar Probe] are specifically designed to solve two key questions of solar physics - why is the sun’s outer atmosphere so much hotter than the sun’s visible surface and what propels the solar wind that affects Earth and our solar system?” Dick Fisher, director of NASA’s Heliophysics Division in Washington, said in 2010. “We’ve been struggling with these questions for decades and this mission should finally provide those answers.”
Data obtained in the pursuit of answering those questions will help back on Earth, too, by improving our ability to forecast space weather (triggered by the sun’s activity), which impacts satellite functionality and affects astronauts.
Before the Parker mission, the closest a manmade object has ever been to the sun occurred in 1976, when a probe called Helios 2 orbited the star at a distance of 27 million miles.