Nasa starts work on two Venus missions to discover its mysterious past

The two missions were chosen based on their potential scientific value and the feasibility of their development plans. The project teams will now work to finalise their requirements, designs, and development plans.

The space agency is awarding approximately $500m (£352m) per mission for development with an expected launch window of 2028-2030.

The first mission, known as DAVINCI+ (Deep Atmosphere Venus Investigation of Noble gases, Chemistry, and Imaging), will measure the composition of Venus’s atmosphere to understand how it formed and evolved, as well as determine whether the planet ever had an ocean.

The mission consists of a descent sphere that will plunge through the planet’s thick atmosphere, making precise measurements of noble gases and other elements to understand why Venus’s atmosphere is a runaway hothouse compared to the Earth’s.

It is also expected to return the first high-resolution pictures of the unique geological features on Venus known as “tesserae,” which may be comparable to Earth’s continents, suggesting that Venus has plate tectonics.

This would be the first US-led mission to Venus’s atmosphere since 1978, and Nasa said the results could reshape our understanding of terrestrial planet formation in our solar system.

The other mission is known as VERITAS (Venus Emissivity, Radio Science, InSAR, Topography, and Spectroscopy) and will map Venus’s surface to determine the planet’s geologic history and understand why it developed so differently from Earth.

Orbiting Venus with a synthetic aperture radar, VERITAS will 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 will also map infrared emissions from Venus’s surface to determine its rock type, which is largely unknown, and understand whether active volcanoes are releasing water vapour into the atmosphere.

“We’re revving up our planetary science programme with intense exploration of a world that Nasa hasn’t visited in over 30 years,” said Thomas Zurbuchen, Nasa’s associate administrator for science.

“Using cutting-edge technologies that Nasa has developed and refined over many years of missions and technology programmes, we’re ushering in a new decade of Venus to understand how an Earth-like planet can become a hothouse. Our goals are profound. It is not just understanding the evolution of planets and habitability in our own solar system, but extending beyond these boundaries to exoplanets, an exciting and emerging area of research for Nasa.”

Last year, an international team of scientists discovered phosphine in the atmosphere of Venus which they believed could point towards the existence of some form of life on the planet.