By serendipity, scientists have photographed Venus’ surface from space for the first time.
Though the planet’s rocky body is concealed beneath a thick veil of clouds, telescopes aboard NASA’s Parker Solar Probe managed to capture the first visible-light images of the surface taken from space, researchers report in the Feb. 16
Though the Parker Solar Probe was built to study the sun, it must make regular flybys of Venus. The planet’s gravity tugs on the probe, tightening its orbit and bringing it closer to the sun. Those assists from Venus helped the spacecraft make headlines when it became the first probe to enter the sun’s atmosphere
It was during two such flybys in July 2020 and February 2021 that the probe’s WISPR telescopes captured the new images. While WISPR found Venus’ dayside too bright to image, it was able to discern large-scale surface features, such as the vast highland region called Aphrodite Terra, through the clouds on nightside.
Clouds tend to scatter and absorb light. But some wavelengths of light get through, depending on the clouds’ chemical makeup, says Paul Byrne, a planetary scientist at Washington University in St. Louis who was not involved in study.
Though scientists knew such spectral windows exist in Venus’ thick clouds of sulfuric acid, the researchers didn’t expect light visible to human eyes would break through so intensely. And while WISPR was designed to study the sun’s atmosphere, its construction also happens to allow it to detect this unanticipated window of light in Venus’ clouds. “It is fortuitous that happened to have an instrument that could see through clouds,” Byrne says.
While flying by Venus in February 2021, NASA’s Parker Solar Probe captured visible light coming from planet’s surface by using the probe’s two WISPR telescopes — WISPR-0 and WISPR-1. Darker regions represent cooler highlands, while lighter regions represent hotter lowlands.
The photographs show a planet so hot that it glows, much like red-hot iron, said Brian Wood, an astrophysicist at the U.S. Naval Research Laboratory in Washington, D.C., and coauthor of the paper, during the social media event.
“The pattern of bright and dark that you see is basically a temperature map,” he said — brighter regions are hotter and darker regions are cooler. This pattern correlates well with topographic maps previously produced from radar and infrared surveys. Highlands appear dark and lowlands appear bright, Wood said.
The images come as NASA prepares to launch two missions to Venus. The new photographs, Wood said, “may help in the interpretation of the observations taken in the future from these new missions.”
Venus is the third brightest thing in the sky, but until recently we have not had much information on what the surface looked like because our view of it is blocked by a thick atmosphere,” said Brian Wood, lead author on the new study and physicist at the Naval Research Laboratory in Washington, DC. “Now, we finally are seeing the surface in visible wavelengths for the first time from space.”
Such images of the planet, often called Earth’s twin, can help scientists learn more about Venus’ surface geology, what minerals might be present there, and the planet’s evolution. Given the similarities between the planets, this information can help scientists on the quest to understand why Venus became inhospitable and Earth became an oasis.
You must be logged in to post a comment.