If you think the summer weather is hot where you live, you should talk to one of the NASA scientists working on the Parker Solar Probe. This unmanned spacecraft is gearing up to boldly go where no probe has gone before: the sun. Set to launch on August 11, 2018 from Cape Canaveral, FL, the Parker Solar Probe will head into the sun’s atmosphere (a.k.a the corona), where it will battle temperatures reaching thousands of degrees Fahrenheit.

How will the spacecraft handle such immense heat without melting like a popsicle? With a little help from Oak Ridge National Laboratory, of course! In order to prepare for their first mission to the sun, NASA used state-of-the-art technology at ORNL to test the Parker Solar Probe’s heat shield. Read on to learn all about Oak Ridge’s contributions to this landmark scientific event.

ORNL’s Vacuum Chamber and “Sun-in-a-Box”

The engineers at the Johns Hopkins University Applied Physics Laboratory were tasked with the challenge of creating a thermal protection system (TPS) for the Parker Solar Probe that can withstand the blistering heat of the sun’s corona. The heat shield that they came up with is made from carbon-carbon sheets, carbon foam, and a special white aluminum oxide coating. Believe it or not, the TPS will keep the probe’s instruments at a comfortable 85 degrees Fahrenheit while the shield faces temperatures of 2,500 degrees Fahrenheit!

Initially, finding a place to test the TPS proved difficult for the Johns Hopkins team. In space, combustion isn’t an issue, but when they tested their heat shield here on Earth, leftover air in test chambers would cause the carbon foam to burn. Fortunately, Oak Ridge National Laboratory provided the perfect solution.

In order to mimic the conditions of outer space (and avoid any combustion-related problems), the engineers built their very own vacuum chamber at ORNL. The scientists also made use of ORNL’s “sun-in-a-box,” a plasma-arc lamp facility that could heat the TPS to corona-level temperatures. The Oak Ridge National Laboratory team exposed the heat shield to 3,227 degrees Fahrenheit for up to 72 hours and simulated solar intensity of 65 watts per square centimeter.

We’re pleased to report that the heat shield passed all of ORNL’s tests with flying colors! You can see a demonstration of NASA’s TPS technology in the video below:

About the Parker Solar Probe’s Mission

The Parker Solar Probe will undertake a seven-year mission to study solar wind, a phenomenon that is responsible for the Northern Lights and for scrambling radio signals and other technology on Earth. The probe is named after Eugene Parker, the scientist who first hypothesized the existence of solar wind in 1958. Now 91 years old, Parker is the first living person to have a NASA spacecraft named after him.

The Parker Solar Probe, which is about the size of a small car, will travel about 4 million miles away from the sun’s atmosphere. Data from the spacecraft should help NASA scientists learn more about how and when solar winds accelerate to supersonic speeds. The probe may also provide insight into why the sun’s corona can reach temperatures that are even higher than the surface of the sun.

Visiting Oak Ridge
From WWII through the present day, Oak Ridge has long been a global leader in science and technology. When you visit the Secret City, you can take a fascinating bus tour that delves into the history of the Manhattan Project and the groundbreaking research conducted at Oak Ridge National Laboratory today. For more information, check out our complete guide to taking a bus tour of Oak Ridge!