This marks the initial direct identification of oxygen on Venus, a planet enveloped by a dense atmosphere rich in carbon dioxide.
While oxygen constitutes approximately 21% of Earth’s atmosphere, Venus presents a contrasting scenario. Its thick and noxious atmosphere is predominantly composed of carbon dioxide (96.5%), with trace amounts of nitrogen and other gases. Oxygen is notably scarce on Venus, making its direct detection challenging, especially given its limited scientific exploration compared to planets like Mars.
Utilizing an instrument aboard the SOFIA airborne observatory, a modified Boeing 747SP aircraft equipped with an infrared telescope through a collaborative effort between NASA and the German Aerospace Center, scientists have successfully identified atomic oxygen in a thin layer nestled between two other layers in the Venusian atmosphere.
Distinguishing atomic oxygen (single oxygen atom) from molecular oxygen (two oxygen atoms), essential for breathing, the researchers made this groundbreaking observation on both the sun-facing and opposite sides of Venus. The oxygen is generated on the day side through solar UV radiation breaking down atmospheric carbon dioxide and carbon monoxide. Winds then transport some of this oxygen to the night side.
The thick atmosphere of Venus, dominated by a greenhouse effect, renders it inhospitable for known Earth organisms. The discovery of oxygen at an altitude of about 60 miles between layers of sulfuric acid clouds and hurricane-force winds sheds light on Venus’s unique atmospheric dynamics. This revelation, attained through direct proof of photochemistry triggered by solar UV radiation, adds a crucial piece to the puzzle of Venus’s evolution and stark differences from Earth.
