NASA selects two Venus missions for Discovery programme

NASA has selected two new missions to Venus, Earth’s nearest planetary neighbour. Part of NASA’s Discovery Programme, the missions aim to understand how Venus became an inferno-like world when it has so many other characteristics similar to ours – and may have been the first habitable world in the solar system, complete with an ocean and Earth-like climate.

These investigations are the final selections from four mission concepts NASA picked in February 2020 as part of the agency’s Discovery 2019 competition.

NASA is awarding approximately $500m per mission for development. Each is expected to launch in the 2028-2030 timeframe.

The selected missions are DAVINCI+ (Deep Atmosphere Venus Investigation of Noble gases, Chemistry, and Imaging) and VERITAS (Venus Emissivity, Radio Science, InSAR, Topography, and Spectroscopy).

DAVINCI+ will measure the composition of Venus’ atmosphere to understand how it formed and evolved, as well as determine whether the planet ever had an ocean. The mission consists of a descent sphere that will plunge through the planet’s thick atmosphere, making precise measurements of noble gases and other elements to understand why Venus’ atmosphere is a runaway hothouse compared to the Earth’s.

In addition, DAVINCI+ will return the first high-resolution pictures of the unique geological features on Venus known as “tesserae,” which may be comparable to Earth’s continents, suggesting that Venus has plate tectonics. This would be the first US-led mission to Venus’ atmosphere since 1978, and the results from DAVINCI+ could reshape our understanding of terrestrial planet formation in our solar system and beyond. James Garvin of Goddard Space Flight Center in Greenbelt, Maryland, is the principal investigator.

VERITAS will map Venus’ surface to determine the planet’s geologic history and understand why it developed so differently than Earth. Orbiting Venus with a synthetic aperture radar, VERITAS will chart surface elevations over nearly the entire planet to create 3D reconstructions of topography and confirm whether processes such as plate tectonics and volcanism are still active on Venus.

VERITAS also will map infrared emissions from Venus’ surface to map its rock type, which is largely unknown, and determine whether active volcanoes are releasing water vapour into the atmosphere. Suzanne Smrekar of NASA’s Jet Propulsion Laboratory in Southern California, is the principal investigator. The German Aerospace Center will provide the infrared mapper with the Italian Space Agency and France’s Centre National d’Etudes Spatiales contributing to the radar and other parts of the mission.

Thomas Zurbuchen, NASA’s Associate Administrator for Science, said: “We’re revving up our planetary science program with intense exploration of a world that NASA hasn’t visited in over 30 years. Using cutting-edge technologies that NASA has developed and refined over many years of missions and technology programs, we’re ushering in a new decade of Venus to understand how an Earth-like planet can become a hothouse. Our goals are profound. It is not just understanding the evolution of planets and habitability in our own solar system, but extending beyond these boundaries to exoplanets, an exciting and emerging area of research for NASA.”

Zurbuchen added that he expects powerful synergies across NASA’s science programmes, including the James Webb Space Telescope. He anticipates data from these missions will be used by the broadest possible cross-section of the scientific community.

Tom Wagner, NASA’s Discovery Programme scientist, added: “It is astounding how little we know about Venus, but the combined results of these missions will tell us about the planet from the clouds in its sky through the volcanoes on its surface all the way down to its very core. It will be as if we have rediscovered the planet.”

In addition to the two missions, NASA selected a pair of technology demonstrations to fly along with them. VERITAS will host the Deep Space Atomic Clock-2, built by JPL and funded by NASA’s Space Technology Mission Directorate. The ultra-precise clock signal generated with this technology will ultimately help enable autonomous spacecraft manoeuvres and enhance radio science observations.

DAVINCI+ will host the Compact Ultraviolet to Visible Imaging Spectrometer (CUVIS) built by Goddard. CUVIS will make high-resolution measurements of ultraviolet light using a new instrument based on freeform optics.

Established in 1992, NASA’s Discovery Programme has supported the development and implementation of over 20 missions and instruments.