Why is Venus so different from Earth? The science driving a flagship-class mission to Venus can be summarized by its three themes:
- What does the Venus greenhouse tell us about climate change? The Venus greenhouse is poorly understood because it is coupled to the still mysterious atmospheric dynamics and cloud physics. To better understand the atmosphere, experiments that simultaneously probe dynamics, chemical cycles, energy balance, and isotopic abundances must be performed, mostly in situ.
- How active is Venus? The search for Venus’ activity ranges from detecting active volcanic processes, to tracking the clouds and logging meteorological data such as the winds, pressures, and temperatures. Detecting ground movement at one location and monitoring the planet globally for seismic events are the most definitive tests for internal structure and activity.
- When and where did the water go? Mineralogical and chemical analyses of Venus’ surface, if done with sufficient precision, have the potential to revolutionize our understanding of Venus’ geology. The ability to analyze both rocks and soils and to drill to depths within pristine rocks holds the key to past changes in atmospheric conditions, volcanism, and climate. Volcanism, tectonism, and weathering affect the climate of Earth in profound ways.
These themes and objectives are summarized in the table below.
the Venus greenhouse tell us about climate change?
- Understand radiation balance in the atmosphere and the cloud and chemical cycles that affect it.
- Understand how superrotation and the general circulation work.
- Look for evidence of climate change at the surface
- Identify evidence of current geologic activity and understand the geologic history.
- Understand how surface/atmosphere interactions affect rock chemistry and climate.
- Place constraints on the structure and dynamics of the interior.
|When and where did the water go?
- Determine how the early atmosphere evolved
- Identify chemical and isotopic signs of a past ocean
- Understand crustal composition differences and look for evidence of continent-like crust
MAJOR OPEN SCIENTIFIC QUESTIONS ABOUT VENUS
- How did Venus evolve to become so different from Earth?
- Was Venus ever habitable, and for how long?
- Did Venus lose a primary atmosphere due to impacts or loss to space?
- What drives Venus' atmospheric superrotation?
- How do geologic activity and chemical cycles affect the clouds and climate
- How are atmospheric gases lost to space?
- What is the volcanic and tectonic resurfacing history of Venus?
- How were the heavily deformed highlands made?
- Is Venus geologically active?
- Did Venus ever have plate tectonics and if so, when did it cease?
- How are geology and climate connected on Venus?
- What has been the role of water and other volatiles in Venus geology?
VENUS INTERIOR STRUCTURE
- Does Venus have Earth-like continents?
- What are the chemical, physical, and thermal conditions of the interior?
- How does mantle convection work on Venus?
- What is the size and physical state of the core?
- What is the structure of the Venus lithosphere?
- How have water and other volatiles affected Venus' interior evolution?
- Was there ever an ocean on Venus, and if so, when and how did it disappear?
- What caused the resurfacing of Venus over the past billion years?
- What is the nature of chemical interactions between surface and atmosphere
- What are the tectonic forces behind Venus' volcanism?
- How were the rocks and soils of Venus formed?
- What do chemical differences of terrains say about the evolution of Venus?