Fastest NASA Space Probe Ever Touches Sun's Corona

The Parker Solar Probe is perhaps NASA’s boldest space project you’ve likely never heard of. Its mission, scientists say, is to “touch” the sun. To be more precise, NASA is flying it closer than any other craft to that fiery gas ball that makes life on Earth possible. 

The probe has broken that record a number of times in 20 solar flybys since its launching in 2018. The most recent close pass happened on June 30. On Christmas Eve, it is projected to come within 3.83 million miles of the sun, the closest ever. The probe will be hurtling around the star at roughly 430,000 miles per hour. That's fast enough to reach Tokyo from New York in about a minute. 

No human-built craft has ever flown so fast. 

"This will be a monumental achievement for all humanity,” project scientist Nour Raouaf told the BBC. He works at Johns Hopkins University. “This is equivalent to the moon landing of 1969." 

Since its launch, the probe has been picking up speed with “gravity assists” from Venus. It's been on a repeated cyclical journey between it and the sun. That journey has pushed the craft faster and closer to the star. The process is like a car traveling up and down a mountain, experts say. Just like a car slows down while climbing, the spacecraft slows as it gets closer to Venus. The car speeds up as it flies downhill. And gravity is what slingshots the probe toward the sun.     

The probe can withstand temperatures of more than a million degrees. It does so because of its custom heat shield and the path it takes through the sun’s corona. Despite the extreme heat, the corona isn’t very dense. Scientists compare the craft’s heat exposure to putting your hand in a hot oven instead of boiling water.   

Reflect: Why do you think exploring the sun or other extreme environments is important for science?