Anasthasia Shilov, Illustrations Editor

Yale astronomers Samuel Cabot GRD ’24 and professor Gregory Laughlin published a study last month in the Planetary Science Journal which investigates a theory suggesting that pieces of Venus may have crashed into the moon.

Cabot and Laughlin’s research offers new insights into recent theories that indicate that Venus could have had an atmosphere similar to that of Earth billions of years ago, before it acquired its current atmosphere, which is dense with carbon dioxide and contains clouds of sulfuric acid. The researchers found that asteroids and comets that crashed into Venus may have dislodged as many as 10 billion rocks, sending them into orbit and causing them to intersect with the Earth and the moon.

“If Venus once had a thin atmosphere,” said Cabot, a graduate student in the Yale Department of Astronomy and the lead author of the study, “then we’d expect to find a certain amount of Venus fragments on the moon.”

The investigation began as Cabot’s one-year project, in which first-year graduate students in the astronomy department are paired with an advisor, conduct research on an area of interest to them and explore the diversity of research opportunities in astronomy. Students have access to a wide range of resources to support their research, including supercomputers and observational tools such as telescopes.

Laughlin, who is a professor of astronomy and physics at Yale, acted as Cabot’s advisor, and together they were inspired by the recent resurgence of interest in space exploration and, in particular, missions to the moon, Cabot told the News. As an example, he mentioned NASA’s Artemis Program –– the “twin sister” of the Apollo space missions.

“With the Artemis program, NASA will land the first woman and next man on the Moon by 2024, using innovative technologies to explore more of the lunar surface than ever before,” stated the project’s website.

The project plans to return humans to the moon but also aspires to eventually send astronauts to Mars. It stands to open up new possibilities for research in space.

With upcoming missions to the moon through Artemis, Cabot and Laughlin wanted to investigate what could be learned about Venus by looking at lunar regolith, the moon’s soil. However, they faced some initial obstacles in answering this question.

“The biggest challenge was where to start,” Cabot said.

The question of whether there could be pieces of Venus on the moon is deceptively simple –– answering it is far more complicated than it seems. During the course of their research, Cabot and Laughlin had to constantly ask themselves if they were using the proper physics, processes and tools to answer the question and double-check whether their findings were consistent with what was physically possible.

They found that it is physically feasible for pieces of Venus to have ended up on the moon, assuming that Venus’ atmosphere was once similar to that of Earth. Cabot explained. However, because his and Laughlin’s work was theoretical, he said, their results will need to be confirmed by the presence of fragments from Venus on the moon. According to him, it is possible that none will be found. Either way, the discovery of rock or lack thereof could provide information about the thickness of Venus’ atmosphere and whether it ever contained liquid water.

Earth is the only planet in the solar system that currently has liquid water. Venus is often referred to as the Earth’s sister planet due to their similar masses, volumes and densities. Their commonalities may even extend to their atmospheres, as Venus may have had one like Earth’s as recently as 700 million years ago, according to a Yale News article.

Cabot and Laughlin’s research could shed light on Venus’ mysterious history. Knowing more about the planet’s past may help researchers better understand what happened to Venus and why its physical characteristics diverged significantly from the Earth’s since its formation.

“We’re quite confident that Venus has a low mass atmosphere in its history [and] that there were plenty of asteroids and comets that blasted pieces of Venus off,” Laughlin told the News. “But understanding exactly what happened to them is one of our biggest challenges.”

Their research also suggests new directions for further exploration. In the future, they hope to obtain physical moon samples from Apollo missions to test their theory.

Cabot emphasized that while these questions seem simple, there are unique challenges to answering them. Although it is possible to compare rock samples with those gathered by Mars rovers to tell whether something originated from Mars, it is much more difficult to do the same for Venus. Unlike Mars, Venus’ current atmosphere could be significantly different from its past atmosphere.

“The next steps are finding the correct fingerprint for Venus and identifying what it takes to identify meteorites from Venus,” he said.

Future research, Cabot explained, must innovate methods for determining a sample’s origins, either through chemical analysis or by studying the isotopic composition of samples. Different amounts of certain isotopes could reveal important insights about when rocks arrived on the moon and where they may have come from.

A day on Venus lasts longer than a year on Earth.

Alexandra Galloway | alexandra.galloway@yale.edu 

Maria Antonia Sendas | mariaantonia.henriquessendas@yale.edu