NASA has announced the DAVINCI (Deep Atmosphere Venus Investigation of Noble Gases, Chemistry, and Imaging) mission from Goddard Space Flight Center as a part of its Discovery Program. Drs. Justin Filiberto and Walter Kiefer of the Universities Space Research Association (USRA) at the Lunar and Planetary Institute (LPI) are science co-investigators on the team that will analyze Venus’ atmosphere to better understand how it formed and evolved, as well as to determine whether Venus ever had an ocean.
Scientists believe that Venus was once more similar to Earth, a world with aqueous oceans that was potentially habitable for billions of years. They suspect that something triggered a ” runaway greenhouse ” effect in Venus’ atmosphere, raising temperatures and vaporizing the planet’s oceans. NASA’s DAVINCI mission will examine Venus in order to establish whether it is livable and to better understand how these similar worlds ended up with such disparate destinies.
“A return to Venus is long overdue as we try to answer the question of why are Earth and Venus — often described as twins in size and composition — so different today?” says Dr. Lisa Gaddis, Director of the LPI. “The LPI is very pleased and proud to be part of this adventure with the DAVINCI team as they address this and many other questions about how the extremely hot, arid and acidic environment on Venus came to be.”
DAVINCI’s science effect will extend beyond the solar system, to Venus-like planets orbiting other stars (exoplanets), which are projected to be common and will serve as significant targets for NASA’s forthcoming James Webb Space Telescope. However, these planets can be difficult to interpret, particularly if they are shrouded in dense Venus-like clouds.
A carrier spacecraft and a probe will be used for the project. The carrier spacecraft will monitor cloud movement and map the surface composition by measuring the amount of heat emitted from Venus’ surface that escapes into space via the vast atmosphere. The probe will descend through the atmosphere, collecting data on its chemistry, temperature, pressure, and wind speed. Additionally, the probe will acquire the first high-resolution photographs of Alpha Regio, an ancient highland twice the size of Texas with craggy mountains, in search of evidence of crustal water influence on surface materials in the past.
“DAVINCI will make detailed measurements of the chemistry of the atmosphere of Venus , revealing key features of its evolution for the first time,” explains Walter Kiefer, a planetary geophysicist at the LPI and a member of the DAVINCI science team. “These observations will tell us about the origin of the atmosphere, whether or not Venus had an ocean early in its history, and how the rate of volcanic activity has varied with time.”
The launch is scheduled for 2029, followed by two flybys of Venus prior to the probe’s entry into and through the planet’s thick clouds. The flybys represent the first stage of the remote sensing mission, which will analyze the atmosphere’s circulation and chart its composition. Around two years later, the probe would be released to undertake an exploration of the atmosphere during an hour-long descent, taking hundreds of measurements along the way before landing at Alpha Regio.
“The Alpha Region landing site is one of the oldest and most geologically complex regions of Venus , similar to continents on Earth,” says Justin Filiberto, another member of the LPI’s science team and a planetary geologist. “DAVINCI will provide the highest resolution imaging ever obtained for Venus , which will reveal the rock composition, the surface weathering environment, and the tectonic processes that shaped this part of Venus .”
The probe will be equipped with four instruments. Two of them – the Venus Mass Spectrometer (VMS) and the Venus Tunable Laser Spectrometer (VTLS) – will conduct the first comprehensive compositional study of Venus’ entire cross-section of atmospheric gases, in the hope of elucidating how, when, and why Venus’ climate may have changed so dramatically. The third sensor, the Venus Atmospheric Structure Investigation (VASI), will monitor pressure, temperature, and winds at a resolution tenfold (or more) than any previous Venus mission. After the probe descended through the dense cloud layer, the Venus Descent Imager (VenDI) instrument captured hundreds of near-infrared photos of the Alpha Regio highlands, which the scientists used to create topographic and composition maps. These photographs will depict distinctive Venusian landscapes at the high resolutions associated with landers (near the surface). Additionally, the probe carries a student-collaborated experiment called Venus Oxygen Fugacity (VfOx), which will determine the amount of molecular oxygen in the atmosphere.
The carrier spaceship will carry only one instrument, a VISOR suite of four cameras (Venus Imaging System from Orbit for Reconnaissance). One camera will be sensitive to ultraviolet light and will be used to monitor the motion of clouds in the atmosphere. Additionally, a system of three near-infrared cameras will be able to determine the surface composition at regional scales by monitoring the near-infrared heat emission from the surface while the spacecraft is passing over Venus’s night side. Given that water may alter the composition of rocks, these photos will shed light on how ancient oceans may have sculpted Venus’s crust. The camera suite will generate the first compositional maps of Ishtar Terra, Venus’s high latitude “continent” with a maximum elevation of 6.8 miles (11 kilometers). Ishtar may be the final manifestation of a type of plate tectonics on Venus that ceased to exist some one billion years ago when the oceans drained. Additionally, the carrier spacecraft carries a technology demonstration experiment, the Compact Ultraviolet to Visible Imaging Spectrometer (CUVIS), which will characterize the Venus clouds’ radiation balance, physical features, and composition.
NASA’s James Garvin The chief investigator is Goddard. Goddard will supervise the mission’s project management and systems engineering efforts.