The images, combined into a video, reveal continental areas, plains and plateaus on our sister planet.

Smothered in thick clouds, the surface of Venus is mostly hidden from view. But during two flybys of the Parker Solar Probe — the probe that has been en route to our parent star for several years — the spacecraft managed to glimpse Venus’ mysterious surface. A special milestone. For it is the first time that images of the Venusian surface in visible light – the kind of light the human eye can see – have been made from space.

Enigmatic Venus

Although Venus shines brightly in the night sky, it is still an enigmatic planet. “Until recently, we didn’t have much information about what the surface looked like,” said Brian Wood, study leader of the in Geophysical Research Letters published study. “That’s because our view is blocked by a thick atmosphere.” While the Parker Solar Probe was in the area, researchers decided to photograph the night side of our nearest neighbor using its built-in Wide-field Imager (or WISPR for short).

Gravity Pendulums Along Venus
Although the focus of Parker Solar Probe is the sun, Venus plays a vital role in the mission. The planet’s gravity is used to bend the orbit of the spacecraft. These gravitational pendulums allow the craft to fly ever closer to the sun. In total, Parker Solar Probe will fly past Venus seven times. During an earlier flyby, the Parker Solar Probe was able to photograph Venus’ dark side. This produced such stunning results that the mission team once again kept their cameras ready during the fourth flyby of the planet, this time immortalizing the entire nightside of Venus.

“The original goal was to measure the speed of the clouds,” said researcher Angelos Vourlidas. But instead of just seeing clouds, WISPR also managed to glimpse the Venusian surface.

Venusian surface

The images, combined into a video, reveal a faint glow from the surface showing distinctive features such as continental areas, plains and plateaus. For example, the images show the Aphrodite Terra region; the largest highland area on the Venusian surface, located near the equator. The Tellus Regio plateau and the Aino Planitia plains also show off in the photos. Because higher elevations are about 30 degrees Celsius cooler than the lower elevations, they appear as dark spots amid the brighter lowlands. A luminous ‘halo’ of atmospheric oxygen can also be seen surrounding the planet.

As Parker Solar Probe skimmed past Venus on its fourth flyby, his WISPR instrument captured these images — combined into a video — revealing the planet’s surface. Image: NASA/APL/NRL

The researchers are extremely enthusiastic about the images produced. “The images and video just blew me away,” Wood says. “We are finally seeing the surface of Venus in visible wavelengths from space for the first time.”

Wavelengths

That we now get a glimpse into the surface of our ‘evil twin sister’ is unique. As mentioned, a dense cloud cover blocks most of the visible light coming from Venus’ surface. But the longest visible wavelengths, which border on the near-infrared wavelengths, manage to penetrate the thick pack of clouds. During the day, however, this light is lost amid the bright sunshine reflected from Venus’ cloud tops. But in the darkness of the night, the WISPR cameras managed to capture this faint glow emitted from the incredibly hot surface. “The surface of Venus is blazing hot even on the night side,” Wood explains. “It is so hot that the rocky surface of Venus glows in visible light, like a piece of iron being pulled from the fire.”

demystifying

Thanks to the images, the researchers hope to learn more about the planet that is often compared to Earth. For example, the photos can help unravel the surface geology of Venus and reveal what minerals are present. In addition, the images could tell more about the evolution of the planet. And the latter is very interesting. Given the similarities between Earth and Venus, this information could help scientists understand why Venus became inhospitable as Earth turned into a veritable oasis.

Satisfied

But for now, the researchers are satisfied with the results achieved. “We are excited about the scientific insights that Parker Solar Probe has provided so far,” said study researcher Nicola Fox. “Parker continues to exceed our expectations. We are excited that these new observations, made during a gravitational pendulum, could help the study of Venus in unexpected ways.”

By the way, it will stay here for a while. During the spacecraft’s next two flybys past Venus, the craft is unlikely to be able to further image the night side. However, scientists will continue to use other instruments equipped with the probe to study Venus. In November 2024, the spacecraft will have one last chance to study the still mysterious surface on its seventh and final flight past Venus.

Did you know…

…several missions to our nearest neighbor will be launched in the near future? Both NASA and ESA have announced their plans for promising missions to Venus. The hope is that the space probes will reveal many secrets about the still enigmatic and uninhabitable planet.