Earth’s evil twin, here we come. NASA’s next two missions, named DAVINCI+ and VERITAS, are heading to Venus, administrator Bill Nelson announced at a news conference June 2.
“These two sister missions both aim to understand how Venus became an inferno-like world capable of melting lead at the surface,” Nelson said. “We hope these missions will further our understanding of how Earth evolved and why it’s currently habitable, when others in our solar system are not.”
The missions were selected from four finalists, two headed to Venus, one to Jupiter’s volcanic moon Io, and one to Neptune’s largest moon Triton. The two Venus missions had applied and been rejected in earlier spacecraft selection rounds.
Venus is almost the same size as Earth, but it seems to have had a different history. Although there’s evidence that it was once covered in oceans and could have been habitable, today it’s a scorched hellscape with clouds of sulfuric acid. No spacecraft has lasted more than two hours on its surface (SN: 2/13/18). And no NASA mission has visited in more than 30 years.
The DAVINCI+ mission includes a probe (illustrated here) that will drop through the Venusian atmosphere, tasting and measuring as it goes. GSFC/NASA
One of the newly selected missions, DAVINCI+, will be the first in decades to send a probe into the planet’s thick, hot atmosphere. The spacecraft will be a ball about a meter in diameter that will sink through Venus’ atmosphere over the course of about an hour, taking measurements of how the content of the planet’s atmosphere changes from top to bottom. The probe will also take some of the highest-resolution photos of the Venusian surface yet on its way down.
Those observations will help scientists figure out how Venus’ water has changed over time, its volcanic activity now and in the past, and the planet’s past potential for habitability (SN: 8/26/16).
“DAVINCI+ is going to give us measurements of the atmosphere that we absolutely, critically need, simply to put some basic bounds on one of the two scenarios for Venus: That it was always the way it is today, or that it was habitable and got ruined,” says planetary scientist Paul Byrne of North Carolina State University in Raleigh. Byrne is not involved in either mission but is on NASA’s Venus exploration committee. The data will also help scientists interpret observations of Earth-sized exoplanets with atmospheres that could be taken with the upcoming James Webb Space Telescope, giving researchers a way to tell exo-Earths from exo-Venuses (SN: 10/4/19).
The other mission, VERITAS, will orbit Venus and study the planet’s surface to figure out its history and why it’s so different from Earth. The orbiter will map the surface with radar, chart elevations to make 3-D maps and look for plate tectonics and volcanism still ongoing on Venus. These observations could provide data for a future mission to land on Venus (SN: 12/23/20).
“We will become acquainted with a brand new Venus with VERITAS,” Byrne says.
The missions are expected to launch sometime between 2028 and 2030, NASA said in a statement.
The European Space Agency is considering another Venus orbiter called EnVision that would provide complementary data to VERITAS and DAVINCI+, if it’s selected. That decision could come as early as next week, Byrne says.
“Having those three missions at Venus would be astonishing,” Byrne says. “It would mean we were finally taking it as seriously as we should have all along.”