Never Give Up, Never Surrender
Back in 2018, before I came to NASA Headquarters as the Planetary Science Division Director, I gave a talk at the 49th Lunar and Planetary Science Conference titled “Exploring Venus: Never Give Up, Never Surrender,” where I laid out the scientific case and mission needs for renewed exploration of Venus in the twenty-first century. It has been more than 30 years since NASA last sent a mission dedicated to exploring the second planet, and for many in the U.S. planetary science community, it felt like Venus had become the forgotten planet. But fast forward to just over three years later, and Venus fans are feeling a lot happier in the wake of the recent selection of the two newest Discovery missions — Venus Emissivity, Radio Science, InSAR, Topography, and Spectroscopy (VERITAS) and Deep Atmosphere Venus Investigation of Noble gases, Chemistry, and Imaging (DAVINCI) — as well as EnVision [as a European Space Agency (ESA) medium-class mission]. (As stated publicly on several occasions, because of my long history of involvement in the Venus community and the DAVINCI mission, I was recused from the Discovery mission selection process.) After many years wandering the proverbial desert, Venus is now back firmly on NASA’s — and ESA’s — exploration agenda.
As an added benefit, the selection of these three missions, to fly in the same time frame, means we will enable science results that are greater than the sum of their individual contributions and we will be able to combine their data to resolve long-standing questions synergistically. Venus’ moment has come at this time because the Venus science community has established a truly compelling set of reasons for us to go back — in a coordinated manner. Space exploration — at its essence — is about stories. It’s about the major driving questions that we seek to answer by visiting the other worlds our solar system offers us.
In terms of size, mass, and distance from the Sun, Venus and Earth are pretty much twins. Yet present-day conditions on the two planets are vastly different. As we try to unravel the history — and predict the future — of Earth (e.g., climate change), studying Venus and learning more about its evolution will help us better understand our own planet. Combining an improved picture of Venus, with the data we have garnered about Mars and its climate history, will provide an even more complete picture of how terrestrial planets with atmospheres evolve. Moreover, the huge increase in the number of confirmed exoplanets — including several that closely orbit their host star — means that we are compelled to better characterize the planets in our own backyard so that we can discern even more about these distant exoplanets. The potential detection of phosphine in Venus’ clouds in the past year, and the rigorous scientific discussion that has followed, also highlight how hungry scientists are to go back to Venus and continue to explore the astrobiological potential of our entire solar system.
VERITAS, DAVINCI, and EnVision have been designed to address all these scientific themes and more. For example, DAVINCI will provide new precise measurements of noble gases and other species in Venus’ atmosphere so that we can study the evolution of Venus’ atmosphere, including the history of water and what led to its “runaway greenhouse” state. DAVINCI will also be providing the first high-resolution pictures of Venus’ tesserae, which are thought to be equivalent to Earth’s continents. In concert with the global high-resolution topography, synthetic aperture radar images, and near-infrared emissivity measurements from VERITAS, we will start to really get a handle on the nature and evolution of Venus’ lithosphere, and may even find that the planet is still geologically and tectonically active.
I’m also extremely proud that NASA will be making a substantial contribution to ESA’s EnVision mission. As part of the mission’s comprehensive payload, aimed to provide an all-encompassing global view of the planet, we will be providing a synthetic aperture radar instrument (VenSAR) that will operate at complementary wavelengths to VERITAS’ InSAR. We will also be providing Deep Space Network support for the mission as well as funding for some U.S. scientists working on the mission. VenSAR will make targeted high-resolution observations of the surface that complement EnVision’s Subsurface Radar Sounder (SRS) and VenSpec, a suite of spectroscopy instruments.
More than just being excited about the science that these missions will yield, I’m aware that by selecting three missions to visit the same planet in a short timeframe, we are investing in people and our community. By creating this major, renewed, focus in planetary science, we have the opportunity now to build the Venus community — engineers and scientists — for the next generation(s). In addition, by having Venus missions from NASA and ESA (as well as the ongoing JAXA Akatsuki mission and the planned 2024 Shukrayaan-1 Venus mission from the Indian Space Research Organisation), we have the chance to create an international, diverse, and sustainable community who will continue to drive the exploration of Venus for many decades.
I also want to acknowledge the hard work of the two mission teams — IVO and TRIDENT — that were not selected this time in the Discovery Program. In an ideal world, we would have the resources to select all the worthy missions, these two included. Working in planetary science and exploration is not for the faint of heart, and I know firsthand how hard it is when something you pour your sweat and soul into for years (or decades) is over in a moment. I hope that those of you who are disappointed after the Discovery selections are finding ways to stay positive. I hope that you will continue working to make your dreams a reality — never giving up and never surrendering. Meanwhile, I hope that you can also celebrate your colleagues’ success. After all, the endeavor of exploring space is a community-wide process. No one person can do it alone. As researchers, we are all driven by our individual curiosities and goals, but when I step back and remember why I originally became a planetary scientist, it wasn’t about a specific question or a specific place; it was about looking up at the sky, wondering what is out there, and how human ingenuity can take us there.
— Lori S. Glaze, Director, NASA’s Planetary Science Division, July 2021