Parker Solar Probe Breaks New Ground with Unprecedented Sun Dive

The mission of NASA to “touch” the sun has validated its successful survival during its unprecedented closest flyby of the solar surface on December 24.

By surpassing its former record, soaring just 3.8 million miles (approximately 6.1 million kilometers) above the sun’s surface, NASA’s Parker Solar Probe raced through the solar atmosphere at an astonishing 430,000 miles per hour (692,000 kilometers per hour)—outpacing any human-engineered object to date. A telemetry tone, captured at the mission operations hub at the Johns Hopkins Applied Physics Laboratory (APL) late on December 26, verified that the spacecraft successfully navigated the encounter and is functioning normally. APL was responsible for the design, construction, and operation of the spacecraft from its facility in Laurel, Maryland.

This flyby, the first of several at this proximity, allows the spacecraft to perform peerless scientific observations with the potential to reshape our comprehension of the sun.

“To achieve such proximity to the sun is a momentous occasion in our effort to unveil the secrets of our closest star,” stated Nicky Fox, associate administrator for NASA’s Science Mission Directorate. “Through close examination of the sun, we can gain deeper insights into its effects on our solar system, including the technologies we rely on daily on Earth, in addition to understanding the dynamics of stars throughout the universe.”

“This achievement exemplifies the commitment and inventive spirit of the entire Parker Solar Probe team,” remarked APL Director Ralph Semmel. “Their remarkable technological advancements have made this extraordinary mission possible, and they have provided crucial new revelations that are transforming our knowledge of heliophysics and space weather.”

For the past six years, Parker Solar Probe has been preparing for this milestone. Launched in 2018, the spacecraft executed seven close encounters with Venus to gravitationally maneuver it closer to the sun. Following the last Venus flyby on November 6, the spacecraft attained its ideal orbit, a lozenge-shaped loop that takes it around the sun every three months—sufficiently close to investigate the sun’s enigmatic mechanisms while avoiding excessive exposure to the sun’s heat and harmful radiation. The spacecraft is set to maintain this orbit for the duration of its primary mission and potentially for many additional years thereafter.

“Parker Solar Probe is enduring one of the harshest environments in space while surpassing all expectations,” stated Nour Rawafi, project scientist for Parker Solar Probe at APL. “This mission heralds a new golden age of space exploration, enabling us to unravel the sun’s most profound and lasting mysteries.”

Near the sun, the spacecraft employs a carbon foam shield to safeguard itself against the extreme heat. The shield was engineered to endure temperatures of 2,600 degrees Fahrenheit (approximately 1,430 degrees Celsius)—sufficient to melt steel—while keeping the instruments behind it maintained at a comfortable ambient temperature. Operators of the spacecraft anticipate that the shield experienced temperatures around 1,800°F (980°C) at its closest encounter.

“It’s monumental to achieve such proximity with a spacecraft to the sun,” commented John Wirzburger, mission systems engineer for Parker Solar Probe at APL. “This has been a challenge that the space science community has aspired to tackle since 1958, advancing technology for decades to make it achievable.”

By passing through the solar corona, Parker Solar Probe can collect measurements that assist researchers in comprehending how this region attains such high temperatures, trace the origins of the solar wind (a continuous flow of material escaping from the sun), and reveal how energetic particles are accelerated to reach nearly half the speed of light.

“The data is crucial for the scientific community as it provides an additional perspective,” explained Kelly Korreck, a program scientist at NASA Headquarters and heliophysicist who contributed to one of the mission’s instruments. “With firsthand observations of activities occurring in the solar atmosphere, Parker Solar Probe has transformed our understanding of the sun.”

Image caption: Within the operations hub of the Parker Solar Probe mission at the Johns Hopkins Applied Physics Laboratory (APL) located in Laurel, Maryland, from left to right, Nick Pinkine, Eliud Bonilla, and Nate Arbor are poised for a communication from Parker Solar Probe signaling its status after its milestone flight on December 24, 2024, just 3.8 million miles (approximately 6.1 million kilometers) from the sun’s surface. The crew verified they received the signal, indicating that Parker was functioning well and performing typically, late on December 26, 2024.

Image credit: NASA / Johns Hopkins APL / Steve Smith

Parker’s 21 preceding approaches have already enabled researchers to gain knowledge about the inner mechanics of the sun. The magnetic field’s zigzag formations, termed switchbacks, detected by the Parker Solar Probe in abundance near the sun provide crucial insights into plasma heating and acceleration. Since April 2021, the spacecraft has been dedicating more time traversing the immediate solar atmosphere—the corona—where the majority of significant physical activities take place.

“We have now comprehended the solar wind and its acceleration originating from the sun,” stated Adam Szabo, a mission scientist for the Parker Solar Probe at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “This close proximity will furnish us with additional data to grasp how it’s accelerated nearer to the sun.”

By navigating through the massive coronal mass ejections near the sun, the Parker Solar Probe has also made several significant findings, particularly showcasing the impact of these structures on their adjacent environment. Observations indicated how these colossal solar explosions sweep aside everything in their path, creating a near-perfect vacuum in their wake. Measurements from the Parker Solar Probe through the narrow shock waves caused by coronal mass ejections are yielding unprecedented insights into the energization of hazardous solar energetic particles.

Flybys of Venus have led to the identification of the shortest wavelength thermal emissions from the planet’s surface, revealing a new avenue to explore the Venusian landscape. Additional observations have produced the first complete image of its orbital dust ring.

So far, the spacecraft has communicated that it is secure, but shortly it will reach a position that will enable it to downlink the data it gathered during this latest solar transit.

“The data transmitted from the spacecraft will provide fresh insights about a location that we, as humanity, have never ventured to,” remarked Joe Westlake, the director of the Heliophysics Division at NASA Headquarters. “It’s an extraordinary achievement.”

The spacecraft’s upcoming planned close solar approaches are scheduled for March 22, 2025, and June 19, 2025.

The Parker Solar Probe was engineered as part of NASA’s Living With a Star program to investigate elements of the sun-Earth system that directly influence life and society. The Living With a Star program is overseen by the agency’s Goddard Space Flight Center in Greenbelt, Maryland, for NASA’s Science Mission Directorate located in Washington. APL manages the Parker Solar Probe for NASA and conceptualized, constructed, and operates the mission.