NASA solar probe to make its closest ever pass of Sun

NASA's Parker Solar Probe is set to make its closest-ever approach to the Sun on Christmas Eve, December 24, at 6:53 a.m. (11:53 GMT), venturing into uncharted territory to deepen understanding of our star.

Launched in August 2018, the spacecraft is on a seven-year mission to explore the Sun's outer atmosphere, or corona, and to study solar wind and space-weather events that affect life on Earth.

During this perihelion — its closest approach — Parker Solar Probe will come within just four yards (meters) of the Sun's surface, relative to the length of an American football field. Traveling at an unprecedented 430,000 mph (690,000 kph), it will endure temperatures of up to 1,700°F (930°C) while its internal instruments remain near room temperature, thanks to a cutting-edge heat shield.

"This is one of NASA's boldest missions," said Arik Posner, Parker Solar Probe program scientist, "doing something no one else has ever done to answer longstanding questions about our universe."

Mission teams will lose direct contact with Parker during this flyby, relying on a "beacon tone" to confirm its status. The spacecraft will begin transmitting science data in the weeks following the encounter.

Parker Solar Probe has already made significant contributions to solar science, investigating how solar winds form, why the corona is hotter than the Sun's surface, and how massive coronal mass ejections are generated.

"By venturing into these extreme conditions, Parker is truly returning data from uncharted territory," said Nick Pinkine, mission operations manager at Johns Hopkins Applied Physics Laboratory.

The December 24 flyby is the first of three record-breaking close passes, with the next scheduled for March 22, 2025, and June 19, 2025.