Venus should have been Earth’s twin, but clearly that’s not the case today, with its thick poisonous atmosphere and barren rocky surface. Now, as part of its Discovery Program, NASA has selected two new missions to Venus to investigate where it all went wrong.
Although it garnered a lot of attention during the early space age, Venus was soon discovered to be a very inhospitable place. The first probes to visit had to contend with clouds of sulfuric acid and the crushing pressures at the surface, which are 92 times stronger than Earth’s at sea level. As such, modern space exploration is focused on our more friendly neighbor on the other side, Mars.
Now, to help unlock some of the mysteries of Earth’s neglected twin, NASA has announced the approval of two new missions to Venus. The first is known as the Deep Atmosphere Venus Investigation of Noble gases, Chemistry and Imaging (DAVINCI+), which will consist of a descent sphere that will dive into the planet’s atmosphere. There, it will analyze the composition of the air using an ultraviolet spectrometer, to investigate whether the planet ever had an ocean.
It will also snap HD images of the planet’s surface, in particular geological features called tesserae that may be similar to continents. If that's what they are, it may suggest that Venus has plate tectonics, a feature currently thought unique to Earth.
The second mission is called Venus Emissivity, Radio Science, InSAR, Topography and Spectroscopy (VERITAS), an orbiter with a focus on studying the surface. The craft will use a synthetic aperture radar to scan the elevation of huge swaths of the planet, with the aim of producing a 3D topographical map. That will help answer questions about whether plate tectonics and volcanism are taking place.
VERITAS will also study infrared emissions from the surface, to try to figure out what kinds of rock it’s made of – an ongoing mystery that might sound surprisingly basic. This will also help reveal whether volcanoes are currently belching water vapor into the atmosphere.
Each mission will receive about US$500 million for development, and are expected to launch between 2028 and 2030. They may not be alone when they get there – private firm Rocket Labs has already announced ambitions to launch a probe to Venus in 2023.
Source: NASA