Venus has been a hot spot in the solar system this week, as two different missions have captured footage of their flybys of the planet. Solar Orbiter, a joint project between NASA and the European Space Agency (ESA), as well as BepiColombo, a joint project between ESA and the Japan Aerospace Exploration Agency (JAXA), both performed flybys of the planet to gain a gravity boost on their way to their destinations of the sun and Mercury respectively.
Solar Orbiter came within 4,967 miles (7,995 kilometers) of Venus on Monday, August 9, capturing its approach using its Solar Orbiter Heliospheric Imager (SoloHI) instrument. SoloHI is designed to image the solar wind, not to capture planetary flybys, but the researchers managing the project wanted to take every chance they had to gather data about our solar system.
They managed to capture Venus approaching, moving from left to right while the sun is on the right. The dark circle of the planet is its nightside, facing away from the sun, which appears black compared to the bright glare of its dayside, which faces the sun.
“Ideally, we would have been able to resolve some features on the nightside of the planet, but there was just too much signal from the dayside,” said Phillip Hess, an astrophysicist at the Naval Research Laboratory in Washington, D.C. “Only a sliver of the dayside appears in the images, but it reflects enough sunlight to cause the bright crescent and the diffracted rays that seem to come from the surface.”
The other view of the planet, shown in the video at the top of this page and in the still image below, was taken by BepiColombo as it came within 324 miles (522 kilometers) of Venus on Tuesday, August 10. BepiColombo couldn’t use its main cameras to image the planet, as they were blocked by another part of the spacecraft, but it could use its small monitoring cameras from its Mercury Transfer Module to snap images as it went by.
The spacecraft approached from the nightside of the planet, but a portion of the dayside is visible as well. Also visible in the image is part of the spacecraft’s solar array, which provides it with power as it continues its long journey to Mercury.
With this flyby complete, BepiColombo will be moving on to flybys of Mercury and won’t be coming back to Venus again. But Solar Orbiter will perform another six Venus flybys over the period of 2022 to 2030 as it approaches the sun.