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Early mission plans didn’t include any planetary science at Venus. But that changed shortly after launch in 2018, and Parker’s better-than-expected performance allowed the team to adjust its observational programs.

One reason Parker’s Venus flybys have become boons for new science is a chance discovery from the spacecraft’s Wide-Field Imager for Parker Solar Probe, called WISPR. The instrument peers out from Parker and away from the Sun to see fine details in the solar wind. But on July 11, 2020, during Parker’s third Venus flyby, scientists turned WISPR toward Venus in hopes of tracking changes in the planet’s thick cloud cover. The images revealed a surprise: WISPR, which captures visible and near infrared light, seemed to see the Venusian surface.

“The WISPR cameras can see through the clouds to the surface of Venus, which glows in the near-infrared because it’s so hot,” said APL planetary scientist Noam Izenberg.

Venus, sizzling at approximately 869 degrees Fahrenheit (about 465 C), was radiating through the clouds.

The WISPR images from the 2020 flyby, as well as the next flyby in 2021, revealed Venus’ surface in a new light. But they also raised puzzling questions, and scientists devised the final flyby to help answer them.

The Venus images correlate well with data from the Magellan spacecraft, showing dark and light patterns that line up with surface regions Magellan captured when it mapped Venus’ surface using radar from 1990 to 1994. Yet some parts of the WISPR images appear brighter than expected, hinting at extra information captured by WISPR. Is WISPR picking up on chemical differences on the surface, where the ground is made of different material? Perhaps it’s seeing variations in age, where more recent lava flows added a fresh coat to the Venusian surface.

“Because it flies over a number of similar and different landforms compared to the previous Venus flybys, the Nov. 6 flyby will give us more context to evaluate whether WISPR can help us distinguish physical or even chemical properties of Venus’ surface,” Izenberg said.

Rawafi said imaging was just part of the flyby’s science agenda. Shaped under Rawafi’s direction for more than a year, the comprehensive plan also included a look at the different components of Venus’ exosphere and their interactions with the Sun. The Parker team expects to begin receiving the first bits of that data later this month, he added, with plans to present some of its findings at the American Geophysical Union’s Fall Meeting the week of Dec. 9 to 13.

“The science data we’ve gathered over these seven Venus flybys is a real tribute to Parker’s versatility, and have enabled new avenues for research on Venus,” Rawafi said. “The seventh Venus flyby, however, was especially unique, in that spacecraft flew through the planet’s nightside and plunged deep into its atmosphere. We’re anticipating some exciting surprises when the data comes down.”

Parker Solar Probe is part of NASA’s Living With a Star program to explore aspects of the Sun-Earth system that directly affect life and society. The Living With a Star program is managed by the agency’s Goddard Space Flight Center in Greenbelt, Maryland, for NASA’s Science Mission Directorate in Washington. APL manages Parker Solar Probe for NASA and designed, built and operates the spacecraft — delivering this flagship heliophysics mission on time and under budget.

For more on Parker Solar Probe, visit APL’s or NASA’s .

This article includes contributions from a NASA web feature story.