For the mission that will get a spacecraft to closest proximity to the sun, NASA has equipped the Parker Solar Probe with a breakthrough heat shield technology.
The historic spacecraft was outfitted with the Thermal Protection System or TPS heat shield on June 27, NASA announced Thursday. The agency has also invited media to see the entire spacecraft on July 13 at the Astrotech Space Operations in Titusville, Florida.
NASA's Parker Solar Probe is set to launch no earlier than Aug. 4 from Cape Canaveral Air Force Station in Florida.
The Heat Shield
TPS is an 8-foot-diameter heat shield designed to protect the spacecraft within its umbra or the shadow it will cast on the spacecraft. When the Parker Solar Probe achieves its closest approach to the sun, temperatures can reach nearly 2,500 degrees Fahrenheit. The heat shield will take most of the heat, allowing only about 85 degrees Fahrenheit of heat penetrating the spacecraft.
TPS is constructed like a sandwich. A carbon foam core, which measures 4.5 inches, is squeezed in between two panels of superheated carbon-carbon composite materials. The side that faces the sun is sprayed with a white coating specially formulated to repel the sun's energy from TPS.
The heat shield weighs only about 160 pounds. It has to be designed as light as possible because when the Parker Solar Probe reached its closest approach to the sun, it will be traveling as fast as 430,000 miles per hour. It will be like traveling from Philadelphia to Washington, D.C., in about one second.
The installation made on June 27 was actually the second time NASA has installed TPS on the spacecraft. The agency has initially installed TPS in 2017 during testing at the Johns Hopkins Applied Physics Lab in Laurel, Maryland.
The current installation, on the other hand, is the final and full integration of the TPS on the Parker Solar Probe.
Parker Solar Probe
Parker Solar Probe will get seven times closer to the atmosphere of the sun, known as the corona. This is something that has not been done by any spacecraft in the past. It will provide experts with the nearest ever observations of a star.
The spacecraft will use Venus' gravity to conduct seven flybys over its almost seven-year long mission. It will fly through the sun's atmosphere as close as 3.8 million miles, entering an orbit well within Mercury. Earth's average distance to the sun is 93 million miles.
Ultimately, the Parker Solar Probe will help experts know about the origin and evolution of the solar wind. It will contribute information that helps experts forecast changes in Earth's space environment that impact life and technology on Earth.