Why we need VERITAS

What is VERITAS?

VERITAS (Venus Emissivity, Radio science, InSAR, Topography And Spectroscopy) is a proposed NASA mission to send an orbiter to Venus to study its surface and unlock the secrets of its past and present.

The mission would map Venus’ surface to determine the planet’s geologic history and understand why it developed so differently than Earth. VERITAS would 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 would also measure infrared emissions from Venus’ surface to map rock types, which are largely unknown, and determine whether active volcanoes are releasing water vapor into the atmosphere.

Why do we need a Venus mission?

One of the great unanswered questions in planetary science is what allowed Earth to develop and maintain its habitability, while Venus became a sulfurous hell.

Venus and Earth have a lot in common, yet are very different in their current state. Both planets have similar size and density, and Venus likely used to have similar conditions to Earth: oceans of liquid water, a mild climate, and other characteristics that may have made it habitable. 

VERITAS would help us understand this transformation by providing for Venus the types of global, high-resolution data sets that have revolutionized our understanding of Mars, Mercury, the Moon, and other bodies.

Despite its scientific interest, similarity to Earth, and proximity, Venus is one of the lesser-studied planets in our Solar System. The last NASA mission to study the Venusian surface from orbit was Magellan, which was active at Venus from 1989 to 1994. Two other international missions have orbited Venus since: Japan’s Akatsuki, and Europe’s Venus Express — but both focused on the Venusian atmosphere rather than its surface. Currently, scientists know more about the surface of Pluto than the surface of Venus despite the latter being so much closer to home.

For these reasons and more, the U.S. planetary science community’s decadal survey, which provides recommendations for the next decade of science exploration, strongly endorsed the VERITAS mission.

What would VERITAS do?

VERITAS would map Venus at 20 times the resolution of Magellan, providing detailed maps of the entire planet’s surface. The maps will help scientists understand how Venus’ surface changes today and how it has transformed over tens of millions of years. From orbit it would also be able to analyze the different rock types found across the planet, which could be instrumental in helping us understand Venus and Earth’s similarities and differences.

VERITAS would additionally be able to search for evidence of current volcanic and tectonic activity. Recent analysis of Magellan images from the early 1990s uncovered potential signs of volcanic activity, but without more data it is hard to know for sure what is happening. VERITAS would provide an unprecedented opportunity for scientists to determine whether the planet is still active, giving us insight into the planet’s inner workings. The spacecraft’s instruments would also measure Venus’ gravitational field, allowing scientists to infer the size of its core and composition of its mantle, and analyze the planet’s atmosphere to help answer the question of whether Venus’ clouds might have signs of life.

Although led by NASA, VERITAS is an international collaboration. The French, German, and Italian space agencies agreed to contribute funding and instruments for the mission.

With other Venus missions coming up, why do we need another?

VERITAS is not the only planned mission to Venus. NASA plans to launch its DAVINCI probe in 2029, and the European Space Agency (ESA) will launch its EnVision orbiter in 2031. Meanwhile, India’s space agency is finalizing the configuration of its first Venus orbiter, Shukrayaan, which will launch sometime before the 2030s on a four-year mission to study Venus’ surface, interior, and atmosphere.

These missions each have unique science goals, however. DAVINCI is designed to study the Venusian atmosphere, not its surface. And EnVision’s mission is to holistically study Venus’ surface, subsurface, and atmosphere rather than focusing on specific surface features. Together, these missions would complement, calibrate, and contextualize each other’s findings.

Combined, these missions would provide us with an extremely comprehensive view of Earth’s sister planet for the first time, helping us understand the delicate physical and chemical balance that ultimately makes Earth habitable and Venus hostile.

What is the current status of VERITAS?

VERITAS is currently delayed, with no clear restart in sight. The mission was being developed by the Jet Propulsion Laboratory (JPL) and was on schedule, on budget, and making great progress with an experienced team. In the November of 2022, NASA delayed the project for at least three years due to cost overruns in another JPL-led mission, Psyche. NASA subsequently removed all development funds for VERITAS, delaying the mission indefinitely.

Why is indefinitely delaying VERITAS a problem?

VERITAS is part of a comprehensive campaign to understand the history and global climate change of Venus — to remove this mission from that effort undermines humanity's ability to better understand the processes that impact terrestrial planets.

It also creates uncertainty and undermines NASA's reliability to the scientific community and its international partners. NASA selected VERITAS for development in 2021 after a grueling, multi-year competition. The scientific case for the mission was already made. It is very unusual for the space agency to cancel a project it just committed to, and doing so undermines NASA's credibility with the scientific community, Congress, and its international partners.

This delay creates significant disruptions in the project, and should it be restarted, the total cost of the mission will inevitably increase. Spacecraft projects can't be switched on and off like a lightbulb; the longer the delay, the higher the cost of the project. International partners likewise may not be able to maintain their commitments to the mission if the delay goes on for too long, leaving a gap for NASA or others to fill.

What needs to be done to save VERITAS?

The Planetary Society recommends that the United States commit to a 2029 launch date and provide the necessary funding to continue mission development. That represents a two-year delay, which gives time for JPL to complete Psyche. The U.S. Congress support VERITAS by establishing this launch date in the report language for the FY 2024 appropriations bill and in future NASA authorization legislation.