NASA’s VERITAS (Venus Emissivity, Radio Science, InSAR, Topography, and Spectroscopy) program represents a renewed effort to explore Venus, a planet often referred to as Earth’s “twin” due to their similarities in size and composition. Despite its hostile environment, Venus holds critical clues about the evolution of rocky planets, including Earth, and understanding these clues may provide insight into how planetary environments can change over time.
VERITAS was selected in 2021 as one of two missions to study Venus, alongside DAVINCI. The VERITAS mission, with its focus on mapping Venus’ surface and examining its geological processes, seeks to answer some of the most pressing questions about the planet’s geological history, tectonic activity, and atmospheric dynamics. This article provides an overview of the VERITAS mission, its objectives, its innovative technology, and its anticipated impact on planetary science.
Overview of the VERITAS Program
The VERITAS mission is designed to conduct an unprecedented study of Venus’ surface, subsurface, and interior. Previous missions have provided tantalizing glimpses into Venus’ thick atmosphere and volcanic surface features, but VERITAS is the first mission equipped to offer high-resolution global mapping of Venus’ topography and to investigate the planet’s interior structure.
VERITAS will utilize advanced radar and spectroscopy techniques to peer through Venus’ dense clouds, which have long obscured the planet’s surface. The mission will generate a detailed map of Venus’ topography, investigate its tectonic and volcanic activity, and provide new data on surface composition and geologic processes. It is scheduled to launch in the late 2020s as part of NASA’s Discovery Program.
Mission Objectives
The VERITAS mission is driven by key scientific objectives aimed at understanding Venus’ past, present, and future. By addressing these objectives, VERITAS hopes to unravel some of the longstanding mysteries surrounding Venus’ geology and its parallels to Earth.
1. Global Surface Mapping
The primary objective of VERITAS is to create high-resolution maps of Venus’ surface using radar imaging. This data will allow scientists to accurately measure the planet’s topography, including the heights and depths of mountains, valleys, and plateaus. These maps will serve as a foundation for studying Venus’ tectonic processes and understanding how its surface has been shaped over time.
2. Tectonic and Volcanic Activity
Venus is a highly volcanic planet, but the extent of its tectonic activity remains unclear. VERITAS will investigate whether Venus is currently geologically active by detecting evidence of recent volcanic and tectonic activity. Understanding the current state of Venus’ interior will help scientists learn whether Venus, like Earth, has a dynamic, molten core that drives plate tectonics and volcanic activity. Additionally, the mission will search for deformations in the surface that indicate ongoing tectonic movement.
3. Surface Composition
VERITAS will employ infrared spectroscopy to analyze the composition of Venus’ surface. By mapping different types of rocks and minerals, scientists can gain insight into the planet’s volcanic history and its long-term climate changes. This investigation will be crucial for determining whether Venus’ surface has been shaped primarily by volcanic activity or by other geologic processes such as erosion or tectonic shifts.
4. Interior Structure
One of the key mysteries of Venus is whether it possesses a layered interior structure similar to Earth’s, including a molten or partially molten core. By using radar data to measure Venus’ gravity field, VERITAS will help scientists determine the planet’s interior density distribution and confirm whether it has a liquid core. This data is essential for understanding the internal dynamics that drive Venus’ geological processes, such as volcanic activity and tectonic deformation.
Key Technologies and Instruments
VERITAS is equipped with several advanced scientific instruments that will enable it to achieve its mission objectives. These tools will provide detailed data on Venus’ surface and subsurface features, allowing scientists to develop a more complete picture of the planet’s geological history.
1. Synthetic Aperture Radar (SAR)
The Synthetic Aperture Radar (SAR) is one of VERITAS’ most important instruments. It will generate high-resolution radar images of Venus’ surface, allowing scientists to see through the planet’s thick clouds and map surface features with unprecedented clarity. SAR is capable of detecting subtle changes in elevation, providing detailed information about Venus’ topography.
The radar will also enable the mission to detect signs of active geology, such as ground deformation caused by tectonic movement or volcanic activity. The data collected will be used to create three-dimensional maps of Venus’ surface, offering insights into the planet’s geological history and the processes that continue to shape it.
2. Interferometric Synthetic Aperture Radar (InSAR)
InSAR is a powerful technique that will be used to detect and measure surface deformations on Venus. By analyzing the interference patterns generated by radar waves reflecting off the surface, InSAR can detect changes as small as a few centimeters in surface elevation. This allows scientists to identify areas where tectonic forces or volcanic activity may be causing the surface to shift or deform.
This capability is essential for determining whether Venus is still geologically active. By comparing radar images taken at different times, InSAR can reveal movements in the planet’s crust, providing evidence of recent or ongoing tectonic and volcanic activity.
3. Venus Emissivity Mapper (VEM)
The Venus Emissivity Mapper (VEM) is designed to measure the thermal radiation emitted by Venus’ surface, providing valuable information about its composition. By analyzing the infrared spectrum of this radiation, VEM will be able to identify different types of rocks and minerals on the planet’s surface. This will help scientists understand the volcanic history of Venus and whether the planet’s surface is dominated by volcanic flows or other geological processes.
The VEM will also be used to study tesserae, which are highly deformed regions of Venus’ crust that may represent some of the planet’s oldest surface features. Understanding the composition of these regions could provide insights into the planet’s early geological history and whether Venus may have once had conditions more similar to Earth.
4. Radio Science Experiment
VERITAS will conduct a radio science experiment to measure Venus’ gravity field. By analyzing the spacecraft’s radio signals as they are affected by Venus’ gravitational pull, scientists can determine variations in the planet’s gravity field. This data will be used to infer details about Venus’ interior structure, including whether the planet has a molten or solid core.
Expected Scientific Impact
VERITAS is expected to revolutionize our understanding of Venus, with far-reaching implications for planetary science and comparative planetology. The data gathered by VERITAS will help answer key questions about Venus’ geological history, its current activity, and the processes that shaped its evolution.
1. Understanding Planetary Evolution
Venus and Earth likely started with similar conditions, but they evolved along vastly different paths. By studying Venus’ geological history, VERITAS will help scientists understand why Venus developed into a planet with a thick, toxic atmosphere and extreme surface temperatures, while Earth became hospitable to life. This knowledge could provide important insights into the factors that determine planetary habitability and the long-term evolution of rocky planets.
2. Comparative Planetology
The study of Venus can offer valuable insights into the processes that shape rocky planets throughout the universe. VERITAS will provide new data that can be compared with similar measurements from Earth, Mars, and other planetary bodies. This comparative approach will allow scientists to develop more comprehensive models of planetary formation, tectonics, and volcanic activity.
Understanding Venus’ tectonic and volcanic activity could also provide clues about exoplanets. By studying how Venus’ geology has evolved over billions of years, scientists can apply this knowledge to the study of rocky exoplanets in distant star systems, helping to determine their potential for habitability.
3. Investigating Planetary Habitability
One of the most intriguing questions about Venus is whether it may have once been habitable. Some scientists believe that Venus may have had oceans and a more temperate climate early in its history, before a runaway greenhouse effect caused the planet to become the inhospitable world it is today. By studying Venus’ surface composition and tectonic history, VERITAS will help scientists determine whether Venus could have supported liquid water in the past, a key factor in assessing its potential for past life.
Importance to Future Missions
The VERITAS mission will lay the groundwork for future exploration of Venus. The detailed maps and data collected by VERITAS will provide valuable information for planning future landers or rovers that could explore Venus’ surface in more detail. Additionally, the mission’s findings about the planet’s tectonic and volcanic activity will help inform the design of instruments for future missions.
VERITAS could also play a key role in astrobiological research. By studying Venus’ past and present conditions, scientists may gain new insights into the factors that determine planetary habitability, both in our solar system and beyond. This knowledge could be crucial for identifying potentially habitable exoplanets and understanding the processes that lead to planetary habitability.
Summary
NASA’s VERITAS mission is set to transform our understanding of Venus, providing unprecedented insights into the planet’s geology, tectonics, and volcanic history. By mapping Venus’ surface with high-resolution radar, investigating its tectonic and volcanic activity, and analyzing its surface composition, VERITAS will address some of the most fundamental questions about Venus’ evolution and its parallels to Earth.
The mission’s findings will have broad implications for planetary science, comparative planetology, and the search for habitable worlds beyond our solar system. VERITAS will provide the detailed data needed to unlock the secrets of Venus, advancing our understanding of rocky planets and their potential for supporting life.
