For the first time, the surface of Venus has been imaged in visible wavelengths from space. The camera on the Parker Solar Probe pierced through the thick Venusian cloud cover and captured blurred but extremely valuable images of the highlands and lowlands of the planet.
The breakthrough images came thanks to a spacecraft with an entirely different mission — the Parker Probe, which has been exploring and progressively nearing the Sun in unprecedented ways. And to get ever closer, it uses trips around Venus to slow down and thereby fly closer to the Sun.
It was during two of those trips around Venus in 2000 and 2001 that the Parker camera, which sees in visible and near infrared wavelengths, was able to image the night side of Venus. This was a first and totally unexpected, since Venus is known to have a dense cover of clouds.
The planet is also, of course, stunningly hot, with a mean temperature of 867 degrees Fahrenheit on the surface. But the temperatures are lower on the elevated Aphrodite Terra, the largest highland region on the Venusian surface, and that is the area that shows as being dark in the images.
“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 in Geophysical Research Letters and a physicist at the Naval Research Laboratory in Washington. “Now, we finally are seeing the surface in visible wavelengths for the first time from space.”
The presentation below, put together by NASA, the John’s Hopkins University Applied Physics Lab and Naval Research Lab, is a stitched together video of the Parker Probe’s Feb. 20, 2021 pass by the dark side of the planet.
Clouds of sulfur dioxide and sulfuric acid obstruct most of the visible light coming from Venus’ surface and so observing from both the ground and from space has relied on radar and observing wavelengths in the infrared that can pierce through the clouds.
But on two passes, the the Parker Probe’s Wide-field Imager for Solar Probe (WISPR) picked up a range of wavelengths from 470 nanometers to 800 nanometers. Some of that light is the near-infrared – wavelengths that we cannot see, but sense as heat – and some is in the visible range, between 380 nanometers and about 750 nanometers.… Read more