NASA’s DAVINCI mission to Venus is scheduled to launch in 2029. A new paper details this journey to come, a daring mission that could shed new light on the scorching planet’s mysterious and potentially habitable past.
Upon arriving at the second planet from the Sun, the probe will dive into Venus’ atmosphere, ingesting its gases for about an hour before landing on the planet’s surface, according to the paper published in The Planetary Science Journal. da vinci is designed to act as a flying chemistry lab, and it will use its built-in instruments to analyze Venus’ atmosphere, temperatures, pressure and wind speed, while snapping some photos of its journey through planetary hell .
Short for Deep Atmosphere Venus Investigation of Noble gas, Chemistry, and Imaging, DAVINCI is one of three next missions planned for Venus, much to the delight of Venus nerds like me. And honestly, it’s been a long time coming. NASA’s last mission to Venus, Magellan, arrived on the planet in 1989 and completed science operations in 1994. Since then, NASA has not sent a specialized mission to Venus, although the planet is, as , super hot, literally and figuratively.
Why is NASA sending a mission to Venus?
Understanding Venus helps scientists get a better view of our own planet. Venus and Earth may have started the same way; the two planets share the same size, mass and density. But today, Venus boasts temperatures of up to 880 degrees Fahrenheit (471 degrees Celsius), with a thick, carbon dioxide-rich atmosphere that traps heat the same way greenhouse gases do on Earth. It also has an eerie volcanic landscape. Something may have happened during the ancient history of Venus to make her develop such brutal and inhospitable conditions, and for it to end up so radically different from Earth.
“Venus’ atmosphere contains the chemical clues to understand a whole range of aspects of this planet, including its starting composition and how its climate has changed over time,” said Paul Byrne, associate professor of Earth and Planetary Sciences at Washington University in St. Louis, who was not involved with the paper, wrote in an email. “The DAVINCI team in particular hopes to establish whether Venus really had oceans of liquid water in its past, and if so, when and why those oceans were lost.”
How will DAVINCI measure the atmosphere of Venus?
To do this, DAVINCI will travel some 38 million miles (61 million kilometers) to Venus. The spacecraft will first perform two flybys of the planet, with the first taking place 6.5 months after launch. During these flybys, the spacecraft will analyze the clouds of Venus and measure the amount of ultraviolet radiation absorbed by the day side of the planet, as well as the amount of heat emitted by the Venusian night side (Venus is not locked by the tides, but it has a very slow rate of rotation).
About two years after launch, the DAVINCI probe, known as the Descent Sphere, will descend into Venus’ atmosphere and sample the various gases as it makes its way to the surface. The 3-foot-long (1 meter long) probe will need an hour to descend, experiencing warmer temperatures and higher pressures as it descends.
“It turns out that the atmosphere of Venus is relatively mild out to about 55 km [35 miles], but quickly starts to get hotter and much denser as you approach the surface,” Byrne said. “To say nothing of the clouds of sulfuric acid, although fortunately they tend to dissipate once you drop to an altitude of around 47 km [29 miles].”
The Descent Sphere is equipped with five instruments designed to measure and analyze the chemistry and environment of the Venusian atmosphere; these tools will hopefully paint a better and more thorough picture of the layered atmosphere. The probe will begin its interactions with Venus’ upper atmosphere when it reaches an altitude of 75 miles (120 kilometers) and it will eject its heat shield when it is 42 miles (67 kilometers) from the ground. As it dives below Venus’ thick cloud layer, about 100,000 feet (30,500 meters) above the surface, the probe will attempt to capture hundreds of images. Venus’ clouds shroud the planet, covering its surface from view, so these images are poised to provide unprecedented views.
In addition to imaging the planet, the Descent Sphere probe will also breathe in part of its atmosphere. “The DAVINCI probe will have a small inlet outside the pressure vessel (essentially a large metal sphere) through which samples of the atmosphere at different altitudes will be sucked into the spacecraft (or, really, pushed as the pressure outside the probe begins to rise significantly above the pressure inside),” Byrne said.
When it lands, the probe should be moving no faster than about 25 miles per hour (40 km/h). If it survives atmospheric entry, the probe will hopefully land in the Alpha Regio Mountains, which are roughly the size of Texas, according to the researchers behind the new paper. Under ideal conditions, the probe will operate for 17-18 minutes once it sticks to landing, but it doesn’t really have to operate on Venus since all the valuable data will have already been collected during its atmospheric dive. .
Is Venus habitable?
Although Venus is a less than ideal place for life today, scientists want to determine whether the planet was ever habitable or not.
In September 2020, a group of scientists claimed that Venus may have signs of life in its clouds bon the detection of what could be phosphine in the Venusian atmosphere. Phosphine is considered a biosignature gas on Earth. However, the results were widely met with skepticism. But whether or not Venus was ever habitable during its past depends on whether the planet once harbored oceans of liquid water or simply had a thick, humid atmosphere.
“The DAVINCI probe will seek to answer this question by measuring the ratios of various gases in the atmosphere,” Byrne said. “These measurements, in turn, will help scientists understand which of their models of climate and interior evolution are correct, and therefore what the likely planetary history of Venus is, including whether it was truly habitable.”