Weee! Parker Solar Probe Completes First Trip Around the Sun

The Parker Solar Probe completed its first complete orbit of the Sun on January 19th, a hallmark moment in the most ambitious mission ever sent to our parent star. All systems aboard the vehicle are in excellent shape, 161 days after launch.

The Parker probe is currently at aphelion, the point of greatest distance between the spacecraft and the Sun. Parker will reach its perihelion, or closest approach of this orbit, on April 4, when it will pass within 15 million miles of our parent star.

“It’s been an illuminating and fascinating first orbit. We’ve learned a lot about how the spacecraft operates and reacts to the solar environment, and I’m proud to say the team’s projections have been very accurate,” said Andy Driesman, from the Johns Hopkins University Applied Physics Laboratory, project manager on the Parker Solar Probe.

An illustration showing the Parker Solar Probe as it orbits the Sun. Image credit: NASA/Johns Hopkins APL/Steve Gribben

The Parker Solar Probe was launched on August 12, 2018, on a mission planned to last for 24 orbits of our parent star. The spacecraft entered full operational status on January 1, and has already returned more than 17 gigabits of data to mission managers on Earth.

At its closest approach of the mission, the Parker Probe will practically skim the surface of the Sun, at a distance of 6.16 million kilometers (3.83 million miles). The heat and radiation experienced by Parker at this time will be the most extreme ever experienced by any spacecraft in history.

“To perform these unprecedented investigations, the spacecraft and instruments will be protected from the Sun’s heat by a 4.5-inch-thick (11.43 cm) carbon-composite shield, which will need to withstand temperatures outside the spacecraft that reach nearly 2,500 degrees Fahrenheit (1,377 degrees Celsius),” NASA reports.

The corona, or atmosphere, of the Sun is unstable, producing flares, the solar wind, and coronal mass ejections. No one knows why the corona is hotter than the surface (photosphere) of the Sun. Our parent star also occasionally ejects millions of tons of highly-magnetized material, which race away from the star at velocities of millions of kilometers an hour. Traveling at these speeds would allow a passenger to travel from New York to Los Angeles in a matter of seconds. By traveling extremely close to the Sun, researchers hope to reveal the answers to some of the great mysteries of our parent star.

In preparation for its second close approach to the Sun this April, mission planners are clearing data that has already been received on Earth from Parker’s memory. New navigational data, as well as additional information, is being sent to Parker, readying it for the next trip around the Sun.

Over the course of seven years, the Parker Space Probe will fly past Venus seven times, gradually reducing the size of its orbit, coming ever-closer to the Sun.

The current position of the Parker Solar Probe as it completes its first journey around the Sun. Image credit: NASA

The Parker Solar Probe will help astronomers answer some fundamental questions about our companion star, including how particles and solar material are ejected at such high velocities from the Sun, and why its atmosphere is hotter than its surface. Researchers also hope that data from the spacecraft will help us better predict solar weather, which can affect satellites and electronics here on Earth.

Aboard the vehicle are the names of more than 1.1 million people from around the globe, lending their support for the Parker probe. The public is also invited to track the spacecraft by viewing a web page showing the location of the vehicle, relative to the planets, as it journeys around the Sun.

The Parker Solar Probe was named in honor of groundbreaking solar scientist Eugene Parker, who was the first person to propose the existence of the solar wind, back in the 1950’s. It is the first NASA mission ever named after a living person.