Touching the Sun
To unlock the mysteries of the solar wind, and to protect a society that is increasingly dependent on technology from the threats of space weather, APL and NASA sent Parker Solar Probe to “touch the Sun.” The mission’s primary science goals are to understand the dynamic nature of the Sun’s coronal magnetic field and plasma, to reveal how the solar corona is heated to such extreme temperatures and to explore what accelerates the supersonic solar wind away from the Sun. It is also exploring mechanisms that accelerate and transport energetic particles, such as coronal mass ejections, at regions never before explored.
The Parker Solar Probe mission is revolutionizing our understanding of the Sun. The mission “touches the Sun,” flying directly through the solar corona, facing brutal heat and radiation conditions and providing unprecedented, close-up observations of the star we live with.
These observations will address unsolved science questions such as how the Sun’s corona is heated and how the solar wind is accelerated. It will also benefit humans on the ground by making critical contributions to our ability to forecast major space weather events that impact life and technology on Earth. Such information can shed light not only on how the Sun drives the space environment in our own solar system, but also provide insight into other stars throughout the universe.
To perform these unprecedented investigations, the spacecraft must use seven Venus flybys over nearly seven years to gradually shrink its orbit, coming as close as 3.83 million miles (6.16 million kilometers) to the Sun, about seven times closer than any spacecraft before it.
Spacecraft and Instruments
Designed, built and operated at APL, Parker Solar Probe carries four instrument suites designed to study electric and magnetic fields, plasma, and energetic particles, as well as image the solar wind.
The spacecraft and instruments are protected from the Sun’s heat by a 4.5-inch-thick (11.43-centimeter-thick) carbon-composite shield, which will withstand temperatures of nearly 2,500 degrees Fahrenheit and radiation equivalent to about 500 times the Sun’s radiation here on Earth. A special cooling system allows the solar arrays to produce power under the intense thermal load from the Sun, and a fault-management system protects the spacecraft during the long periods of time when it can’t communicate with Earth.
In 2017, the spacecraft and mission were renamed after Eugene Parker, who in the 1950s proposed the concept of the solar wind. This is the first NASA mission to have been named for a living individual.
Results and Expectations
Parker Solar Probe has already begun to revolutionize our understanding of the Sun. A deeper understanding of the nature of the solar corona and processes occurring between the Sun and the Earth will also benefit humans on the ground by potentially contributing to our ability to forecast space weather events that impact life and technology on Earth and human spaceflight operations.
Parker Solar Probe already holds the records for the closest approach to the Sun (within 12 million miles) and for being the fastest human-built object (traveling at more than 280,000 miles per hour).
Parker Solar Probe is operating normally, having just completed its sixth science-observation orbit around the Sun.
August 12, 2018
October 3, 2018; December 26, 2019; July 11, 2020; February 20, 2021; October 16, 2021; August 21, 2023; November 6, 2024
First Solar Perihelion (Close Approach)
November 5, 2018
Final Solar Perihelion (Closest Approach)
June 19, 2025
Helene Winters, Johns Hopkins APL
Nour Raouafi, Johns Hopkins APL
Arik Posner, NASA Headquarters
Adam Szabo, NASA Goddard Space Flight Center