A Pakistan-born German astrobiologist has identified life-supporting organic molecules beneath the icy crust of Enceladus, one of Saturn's moons, adding fresh evidence that it may harbor the conditions necessary for life.
The discovery was made by Dr. Nozair Khawaja, a researcher at Freie Universität Berlin, whose findings were published on October 1 in the journal Nature Astronomy. His team analyzed data collected by NASA's Cassini spacecraft, which explored Saturn and its moons for more than a decade before its mission ended in 2017.
Dr. Khawaja's team examined ice grains ejected from Enceladus's south polar geysers plumes that originate from the subsurface ocean and release a mixture of water, gas, and dust into space. Their analysis revealed complex organic molecules, including ethers, alkenes, esters, and aromatic compounds.
Dr. Khawaja explained:
We found several types of organic molecules containing oxygen bridges, single and double carbon bonds, and ring-shaped carbon structures. These compounds are known intermediates in chemical reactions that can lead to the formation of more complex molecules, such as those required for life.
He added that although these molecules can form without biological processes, their presence provides critical clues about the chemical environment within Enceladus's hidden ocean.
Scientists generally agree that three factors are needed to sustain life: liquid water, an energy source, and essential chemical compounds. Enceladus contains all three, despite its small size of just 505 kilometers in diameter.
Data from Cassini's Cosmic Dust Analyzer detected phosphates, one of the six key elements of life: carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur (CHNOPS). The spacecraft also recorded evidence of hydrothermal vents on Enceladus's ocean floor, similar to those found in the Lost City Hydrothermal Field in the Atlantic Ocean, where microbial life thrives on Earth.
Dr. Khawaja added:
One of the most important aspects of this research is that the organic samples were collected just minutes after ejection. They were not altered by space radiation, which confirms that they came directly from the moon's ocean.
Dr. Khawaja said that while the presence of life on Enceladus remains unconfirmed, the discovery strengthens the moon's case as one of the most promising locations in the search for extraterrestrial life. "We don't yet know whether life exists there, but Enceladus remains one of the best places in our solar system to find out," he said.
Dr. Khawaja was born in Wazirabad, Punjab, and completed his Master's in Astronomy and Space Sciences at Punjab University before earning a PhD in Geosciences from Heidelberg University, Germany. He later worked as a postdoctoral researcher at the Institute of Earth Sciences in Heidelberg, focusing on planetary habitability and extraterrestrial chemistry.