NASA’s Parker Solar Probe will break new records as it passes closer to the sun than any spacecraft before on Christmas Eve. At 6:40 a.m. Eastern Time on Dec. 24, the probe will fly within 3.8 million miles of the sun’s surface — over seven times closer than previous missions. During this record-breaking flyby, Parker will reach speeds of 430,000 miles per hour, becoming the fastest human-made object in history.
NASA’s Nicky Fox describes this mission as a thrilling “voyage of discovery.” Parker’s mission is groundbreaking because no spacecraft has ever ventured so close to a star’s atmosphere. Since its 2018 launch, the probe has made steady progress, completing 21 flybys — called perihelions — and providing invaluable data about the sun. This mission, a joint effort by NASA and the Johns Hopkins Applied Physics Laboratory, has also enhanced our understanding of Venus and allowed scientists to observe comets.
The Parker Solar Probe faces significant challenges, particularly the extreme heat from the sun’s proximity. The spacecraft is equipped with a heat shield to protect it from temperatures approaching 2,000 degrees Fahrenheit. Despite these risks, the mission has exceeded expectations, though its success still hinges on careful monitoring, as unforeseen issues could arise at any moment.
In previous flybys, Parker has traveled through the Alfvén surface, a region where solar wind — the stream of particles emitted by the sun — escapes into space. This time, the spacecraft will fly even closer, into uncharted territory of the sun’s outer atmosphere. Scientists are eager to study this new area, as it could provide valuable insights into how the solar wind is accelerated and the dynamics of the sun’s corona.
Adding to the excitement, the sun is currently in its most active phase, known as the solar maximum. This increases the likelihood that the Parker Solar Probe will witness dramatic events such as coronal mass ejections (CMEs), which are massive bursts of plasma released from the sun. The team is hoping to study these explosive events, which could help uncover the mechanisms that drive the sun’s energy.
The spacecraft will temporarily be out of contact until Dec. 27, when it is expected to send a health status update back to Earth. If all goes as planned, the Parker Solar Probe will continue to relay groundbreaking data from its solar journey. With enough fuel for several more years of exploration, the spacecraft has two more flybys scheduled for 2025, but it will never get any closer to the sun.
The mission’s success is the result of decades of planning. One of the biggest challenges was finding a way to get the spacecraft so close to the sun. Unlike other missions, which use gravity assists from planets to increase speed, the Parker mission required a unique approach. Mission designer Yanping Guo devised a plan involving seven gravity assists from Venus to gradually guide the spacecraft toward the sun.
Named after solar physicist Eugene Parker, who first predicted the existence of the solar wind in the 1950s, the Parker Solar Probe has already made significant discoveries. It has observed magnetic “switchbacks” that help explain the solar wind and confirmed the existence of a dust-free zone near the sun, a theory proposed in 1929.
These findings not only deepen our understanding of the sun but also have practical implications for protecting Earth from space weather. Additionally, the data gathered may provide clues about the possibility of life around other stars.
As the Parker Solar Probe continues its mission, the future of solar research looks promising. Project scientist Nour Rawafi expressed his excitement for future generations to build on this work, wishing he could relive the journey of discovery.