By flying closer to the Sun than ever, Parker Solar Probe reveals the chaotic birthplace of solar wind and space storms, offering clues that may boost Earth’s defenses. Credit: NASA GSFC/CIL/Brian Monroe
NASA’s Parker Solar Probe is revolutionizing our understanding of the Sun by flying closer than ever before, capturing jaw-dropping images from within the solar atmosphere.
- NASA’s Parker Solar Probe has captured the most detailed images ever taken near the Sun, recorded from just 3.8 million miles away from its surface.
- These up-close images reveal structures within the solar wind, a continuous flow of charged particles that the Sun releases into space at speeds over 1 million miles per hour.
- The new visuals and data are giving scientists critical insights into how the solar wind forms and behaves, which is key to understanding how it influences Earth.
Parker Solar Probe Reveals Never-Before-Seen Views of the Sun
During a historic flyby of the Sun in late 2024, NASA’s Parker Solar Probe captured remarkable new images from deep inside the Sun’s atmosphere. Taken closer to the Sun than any spacecraft before, these visuals are offering scientists valuable insights into how the Sun shapes the space environment throughout the solar system, including the forces that can impact Earth.
“Parker Solar Probe has once again transported us into the dynamic atmosphere of our closest star,” said Nicky Fox, associate administrator, Science Mission Directorate at NASA Headquarters in Washington. “We are witnessing where space weather threats to Earth begin, with our eyes, not just with models. This new data will help us vastly improve our space weather predictions to ensure the safety of our astronauts and the protection of our technology here on Earth and throughout the solar system.”
The spacecraft began its closest approach to the Sun on December 24, 2024, coming within just 3.8 million miles of the solar surface. As it passed through the corona, the Sun’s outer atmosphere, in the days surrounding its closest point (known as perihelion), it gathered scientific data using several onboard instruments, including the Wide-Field Imager for Solar Probe (WISPR).
Parker Solar Probe has revolutionized our understanding of the solar wind thanks to the spacecraft’s many passes through the Sun’s outer atmosphere. Credit: NASA’s Goddard Space Flight Center/Joy Ng
Inside the Solar Wind: Dynamic Forces Unleashed
The new WISPR images reveal the corona and solar wind, a constant stream of electrically charged particles from the Sun that rage across the solar system. The solar wind expands throughout of the solar system with wide-ranging effects. Together with outbursts of material and magnetic currents from the Sun, it helps generate auroras, strip planetary atmospheres, and induce electric currents that can overwhelm power grids and affect communications at Earth. Understanding the impact of solar wind starts with understanding its origins at the Sun.
The WISPR images give scientists a closer look at what happens to the solar wind shortly after it is released from the corona. The images show the important boundary where the Sun’s magnetic field direction switches from northward to southward, called the heliospheric current sheet. It also captures the collision of multiple coronal mass ejections, or CMEs — large outbursts of charged particles that are a key driver of space weather — for the first time in high resolution.
“In these images, we’re seeing the CMEs basically piling up on top of one another,” said Angelos Vourlidas, the WISPR instrument scientist at the Johns Hopkins Applied Physics Laboratory, which designed, built, and operates the spacecraft in Laurel, Maryland. “We’re using this to figure out how the CMEs merge together, which can be important for space weather.”
This video, made from images taken by Parker Solar Probe’s WISPR instrument during its record-breaking flyby of the Sun on December 25, 2024, shows the solar wind racing out from the Sun’s outer atmosphere, the corona. Credit: NASA/Johns Hopkins APL/Naval Research Lab
When CMEs collide, their trajectory can change, making it harder to predict where they’ll end up. Their merger can also accelerate charged particles and mix magnetic fields, which makes the CMEs’ effects potentially more dangerous to astronauts and satellites in space and technology on the ground. Parker Solar Probe’s close-up view helps scientists better prepare for such space weather effects at Earth and beyond.
The solar wind was first theorized by preeminent heliophysicist Eugene Parker in 1958. His theories about the solar wind, which were met with criticism at the time, revolutionized how we see our solar system. Prior to Parker Solar Probe’s launch in 2018, NASA and its international partners led missions like Mariner 2, Helios, Ulysses, Wind, and ACE that helped scientists understand the origins of the solar wind, but from a distance. Parker Solar Probe, named in honor of the late scientist, is filling in the gaps of our understanding much closer to the Sun.
At Earth, the solar wind is mostly a consistent breeze, but Parker Solar Probe found it’s anything but at the Sun. When the spacecraft reached within 14.7 million miles of the Sun, it encountered zig-zagging magnetic fields — a feature known as switchbacks. Using Parker Solar Probe’s data, scientists discovered that these switchbacks, which came in clumps, were more common than expected.
Discovering Magnetic Switchbacks Up Close
When Parker Solar Probe first crossed into the corona about 8 million miles from the Sun’s surface in 2021, it noticed the boundary of the corona was uneven and more complex than previously thought.
As it got even closer, Parker Solar Probe helped scientists pinpoint the origin of switchbacks at patches on the visible surface of the Sun where magnetic funnels form. In 2024, scientists announced that the fast solar wind — one of two main classes of the solar wind — is in part powered by these switchbacks, adding to a 50-year-old mystery.
However, it would take a closer view to understand the slow solar wind, which travels at just 220 miles per second, half the speed of the fast solar wind.
This artist’s concept shows a representative state of Earth’s magnetic bubble immersed in the slow solar wind, which averages some 180 to 300 miles per second. Credit: NASA’s Goddard Space Flight Center Conceptual Image Lab
“The big unknown has been: how is the solar wind generated, and how does it manage to escape the Sun’s immense gravitational pull?” said Nour Rawafi, the project scientist for Parker Solar Probe at the Johns Hopkins Applied Physics Laboratory. “Understanding this continuous flow of particles, particularly the slow solar wind, is a major challenge, especially given the diversity in the properties of these streams — but with Parker Solar Probe, we’re closer than ever to uncovering their origins and how they evolve.”
The slow solar wind, which is twice as dense and more variable than fast solar wind, is important to study because its interplay with the fast solar wind can create moderately strong solar storm conditions at Earth sometimes rivaling those from CMEs.
Prior to Parker Solar Probe, distant observations suggested there are actually two varieties of slow solar wind, distinguished by the orientation or variability of their magnetic fields. One type of slow solar wind, called Alfvénic, has small-scale switchbacks. The second type, called non-Alfvénic, doesn’t show these variations in its magnetic field.
As it spiraled closer to the Sun, Parker Solar Probe confirmed there are indeed two types. Its close-up views are also helping scientists differentiate the origins of the two types, which scientists believe are unique. The non-Alfvénic wind may come off features called helmet streamers — large loops connecting active regions where some particles can heat up enough to escape — whereas Alfvénic wind might originate near coronal holes, or dark, cool regions in the corona.
In its current orbit, bringing the spacecraft just 3.8 million miles from the Sun, Parker Solar Probe will continue to gather additional data during its upcoming passes through the corona to help scientists confirm the slow solar wind’s origins. The next pass comes September 15, 2025.
“We don’t have a final consensus yet, but we have a whole lot of new intriguing data,” said Adam Szabo, Parker Solar Probe mission scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
