VERITAS, short for Venus Emissivity, Radio Science, InSAR, Topography & Spectroscopy, will send an orbiter that would produce high-resolution three-dimensional global maps using radar, and a spectrometer will identify what the surface is made of. It will also precisely measure variations in the planet’s gravitational pull, which will offer clues to its interior geological processes.
Studying Venus will also shed light on the other rocky planets in the solar system including Earth. “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,” Mr. Nelson said.
NASA’s last spacecraft dedicated to exploring Venus, Magellan, arrived in 1990, and it spent four years mapping the planet’s surface with a sophisticated radar instrument.
Since then, NASA has successfully sent a parade of spacecraft to Mars — five rovers, four orbiters and two landers — striving to understand the history of water and the possibility of life on the red planet. But the agency has sent none to Venus.
Even before the phosphine announcement, many planetary scientists were pushing for a return visit.
In 2017, VERITAS and DAVINCI were among the finalists in the last round of NASA’s Discovery program, but the space agency chose two asteroid missions instead.
Also in 2017, for the larger, more expensive New Frontiers competition, NASA considered a Venus mission called Venus In situ Composition Investigations, or Vici, which sought to put two landers on the planet’s surface. It was passed over for Dragonfly, which will send a plutonium-powered drone to fly on Titan, the largest moon of Saturn.
In addition, planetary scientists are in the middle of putting together their once-a-decade recommendations to NASA about their priorities. NASA usually undertakes only one flagship mission — a big, ambitious, expensive effort — at a time. A Venus flagship mission under consideration would include two balloons that would float in the atmosphere for a month.