Two spacecraft are set to swoop past Venus within hours of each other this week, using the maneuver to do a little bit of bonus science on the way to their main missions at the center of our solar system.
The European Space Agency's Solar Orbiter probe, a cooperation with NASA, will swing around Venus early Monday, using the planet's gravity to help put it on a course to observe the Sun's poles.
About 33 hours later, the European-Japanese spacecraft BepiColombo will get even closer to Venus in a maneuver designed to help it slow down sharply and safely steer into the orbit of Mercury in 2025.
“Without the flyby, we would not be able to reach our target planet," said Elsa Montagnon, the spacecraft operations manager for BepiColombo. "The energy required to enter into orbit of Mercury would be prohibitively expensive in terms of propellant.”
Both probes have numerous scientific instruments on board, some of which will be used to take a closer look at Venus as they zoom past, according to an Associated Press report.
The measurements will add to those taken by the Japanese probe Akatsuki, which is already in orbit around Earth's hotter neighbor. NASA and the European Space Agency are planning to send three more missions to Venus toward the end of the decade.
The third of these three missions is called EnVision, which the European Space Agency announced will be launched in the early 2030s. This orbiter will attempt to explain why Venus is so “wildly different” from Earth, even though the two are similar in size and composition.
According to the space agency, the scientific instruments onboard EnVision will tackle some of the big remaining questions about the two planets. It will be equipped with a suite of European instruments, including a sounder to reveal underground layering, and spectrometers to study the atmosphere and surface. "The spectrometers will monitor trace gases in the atmosphere and analyse surface composition, looking for any changes that might be linked to signs of active volcanism," an official statement on the mission explained earlier this year.
The statement further explained that a Nasa-provided radar will image and map the surface. Additionally, a radio science experiment will probe the planet's internal structure and gravity field as well as investigate the structure and composition of the atmosphere. EnVision is also expected to significantly improve on the radar images of the surface obtained by Nasa's Magellan in the 1990s, an Associated Press report explains. The spacecraft will work together with Nasa's DAVINCI+ and VERITAS missions to provide the most comprehensive study of Venus ever.