As Rocket Lab prepares to launch a mission to Venus next year, a multidisciplinary research team led by Georgia Tech braved an erupting volcano recently to test an instrument custom-built to explore Venus’ clouds and look for signs of organic chemistry. If successful, the 2026 launch will mark the first private spacecraft to reach Venus, and the first U.S. mission to study its sulfuric acid-filled clouds in nearly 40 years.

The instrument, the autofluorescence nephelometer (AFN) built by Droplet Measurement Technologies, will fire a laser beam out a window and use light scattering from individual particles to measure the size and composition of the planet’s aerosols, the tiny particles that make up the clouds. The AFN will only have about five minutes to collect data as the small probe falls through the clouds, and another 15 minutes to send data back to Earth before things get too extreme. The probe is not expected to reach the surface, where it is hot enough to melt lead, and the pressure is 90 times that of Earth’s surface.

Georgia Tech oversees all of the instrument’s field tests and modeling. The project, called VENUSIAN, is led by Christopher E. Carr, assistant professor in the Daniel Guggenheim School of Aerospace Engineering, with funding from NASA’s PSTAR program. Carr holds a joint appointment in the School of Earth and Atmospheric Sciences.

NASA also built a heat shield for Rocket Lab’s spacecraft and will provide navigation and communications support through the Deep Space Network.

“Is there life in the clouds of Venus? I don’t think so, but if it’s there, I want to find it,” says Carr, who admits that the more he studies Venus, the more interesting it becomes. 

Collecting Volcanic Molecules

In March, his team tested the AFN in the field, flying it on a drone through Hawaii’s volcanic fog, a haze that forms because of volcanic emissions. The droplets are rich with sulfuric acid, similar to Venus’ atmosphere. 

“We got some valuable data,” says Carr. “This was the first time for our whole team from different institutions to be together in one place.” 

Collaborators from the Massachusetts Institute of Technology (MIT), the University of Colorado-Boulder, which managed and flew the drones, and Droplet Measurement Technologies joined the Georgia Tech contingent in Hawaii.

Sara Seager, professor of physics, professor of aeronautics and astronautics, and Class of 1941 Professor of Planetary Science at MIT, who serves as the science principal investigator for the Rocket Lab mission, emphasized the critical testing role Georgia Tech is playing ahead of the mission to Venus.

“Building the instrument is important, but what is also important is knowing how you’re going to interpret data when you get back. To understand that you need to use the instrument over and over again here on Earth. Professor Carr taking a lead on that from a science perspective is important,” says Seager, who will oversee two subsequent Morning Star Missions to Venus that the team envisions will culminate in an atmosphere sample return.

The Kilauea volcano, located in Hawaii Volcanoes National Park on the Big Island, began erupting as soon as the team started their first drone flight. The eruption grew more intense on the second day, giving the researchers a chance to run the AFN through its paces. While the flight test results are still preliminary, the team indicated that the instrument did detect volcanic ash and volcanic smog, which bodes well for the Venus mission. 

“It was cool to see our instrument in action,” says Snigdha Nellutla, a research engineer and data modeler, who recently finished her master’s in aerospace engineering. She simulates the AFN’s output in different environmental conditions, both during the Hawaii field tests and on the actual mission to Venus.

In Search of a Carbon Cycle

“We’re seeking evidence of a carbon cycle in the Venus atmosphere,” she said. “Life as we know it on Earth is carbon-based. Carbon compounds are delivered to Venus from meteorites. Are they rapidly degraded or do they persist in some form?”

Billions of years ago, Venus may have had as much water as Earth — but at some point in its evolution, carbon dioxide in the planet's atmosphere triggered an intense runaway greenhouse effect. This sent temperatures soaring, causing the planet's water to evaporate, and the hydrogen part of the water (H2O) was lost to space.

In 2020, astronomers detected phosphine in Venus’ atmosphere. This gas, often associated with biological activity on Earth, could signal signs of life. While the presence of phosphine is now debated, a rash of recent discoveries suggests that organic chemistry in the clouds could be much more complex than previously considered.

While Venus’ extreme surface temperatures are well documented, the one exception is found in the middle cloud layers, which have habitable temperatures. By looking at individual particles within the Venus atmosphere, researchers hope to learn about other compounds that could exist, including organic molecules that could influence a carbon cycle. The Hawaii measurements will serve as an important baseline to compare against what will be gathered on Venus. 

The Smoking Gun of Organics

The mission to Venus will also measure fluorescence, considered “a smoking gun” for possible organic materials, says Carr. 

On Venus’ super-rotating atmosphere, clouds take four Earth days to travel around the planet, while the planet spins in the same direction approximately 50 times slower.

“The differences with Venus’s atmosphere compared with Earth have forced our whole team to look at how we approach astrobiology completely differently,” he explains. “When we think of finding signs of life, we follow the water, but Venus has no water; it’s sulfuric acid.”

To Carr, the importance of the mission is to better understand Venus’ chemistry, given that sulfuric acid and water have different properties, which can contribute to or limit the kind of chemistry that can occur. 

“By understanding what might be possible, we can learn if different types of life might be possible. It also helps us know what to look for when we look for life,” he says. Even if there is no life in the clouds of Venus, there is likely to be interesting chemistry, based on extensive testing by members of the science team. This chemistry could be detected by the AFN as fluorescent aerosol particles.

VENUSIAN has enabled Georgia Tech aerospace engineering students to get a rare opportunity to test and model hardware that will fly in space. 

Students Celebrate Teamwork, Space Aspirations  

“As a first-year, I’ve had a variety of tasks, and that’s been fun for me as someone who is just starting to explore my career possibilities,” says Violet Oliver, who oversees the ground sampling tests. “This has been a really good introduction — getting my feet wet in what future space missions might look like and, more broadly, what the engineering test cycle looks like.”

“The biggest thing we learned was how to work together as a team,” adds Cassius Tunis, a senior in aerospace engineering. He managed the logistics, designed hardware to integrate the AFN and the drone, and served as the field study’s test engineer during the flights, where he communicated with the pilots and tracked their flight pattern.

“It’s been a goal of mine to work in the space industry since high school,” he said, crediting VENUSIAN with helping him pinpoint his career direction. “I see myself as the resident test engineer. Test engineering is a very operational, multidisciplinary field within aerospace. You get to wear a lot of different hats and interact with people of all different backgrounds.”

Carr indicated that the team will return to Hawaii later this year for final AFN field testing before the Venus mission. 

Looking to the 2026 launch, Seager says, “I’m looking forward to a safe launch and getting exciting data back. It’s Venus’ moment to shine,” she added, calling Venus the “quiet, overlooked gem” to Mars and Earth.

Carr expressed admiration for Rocket Lab’s founder and CEO, Peter Beck, whose passion for the Venus mission is well documented. 

“He exudes the true curiosity of a scientist and explorer. In Rocket Lab, we have a partner that is excited by discovery.”