The Parker Space Probe is getting ready for it’s moment under the hot lights. As NASA preps the probe to get closer to the sun than any human-made object in history, it’s Thermal Protection System (TPS) has been installed.
The Parker will be entering the sun’s corona, an envelope of plasma that surrounds the star. Solar coronas extend millions of miles into space, and the Parker will get within 4 million miles of the sun. This will mark the closest humanity has ever gotten to the star that is responsible for all known existence in the universe, and the Parker will give unprecedented information about the inner workings of a star’s corona.
The Parker will be reliant on its TPS to keep it from getting roasted. Eight feet in diameter, it will keep everything under its umbra, the darkest part of a shadow, at a safe temperature. As the Parker enters the sun’s corona, the heat shield’s temperatures will hit 2,500 degrees Fahrenheit. Under the umbra, however, things will stay around 85 degrees Fahrenheit, perfect beach weather.
Perhaps the most surprising element of the TPS is its weight. The shield that will keep a space probe safe from the onslaught of the sun’s heat only weighs 160 pounds. That weight comes from design and function meeting head-on: the Parker needs all the speed it can get to achieve orbit. Comprised of two panels of superheated carbon-carbon composite on either side of a lightweight 4.5-inch-thick carbon foam core, that core is 97 percent air.
This attachment of the TPS is a reunion of sorts. The shield was first attached to the Parker in testing in 2017, but this time is different. This is permanent, the first time the Parker has been fully integrated before its launch in August.
The Parker has all sorts of clever tricks to keep it from overheating, from solar arrays that won’t crack under the temperatures to pressurized waters. It will likely need them all.