Scientists Discover Massive 6,000-Mile-Long Water Plume Escaping Saturn’s Moon

Scientists from the Southwest Research Institute (SwRI) have made an astounding discovery while observing Saturn’s moon, Enceladus, using the James Webb Space Telescope (JWST). The team observed a colossal plume of water vapor, stretching over 6,000 miles, which is equivalent to the distance between the United States and Japan. Dr. Christopher Glein, an expert in extraterrestrial oceanography from SwRI, was awarded a Cycle 2 allocation to further investigate this remarkable plume and analyze the essential chemical compounds on Enceladus’ surface. This study aims to gain a deeper understanding of the moon’s potential habitability as an oceanic celestial body.

Enceladus, already known for its dynamic nature, has been a prime target in the search for extraterrestrial life beyond Earth. The Cassini spacecraft, during its comprehensive 13-year examination of the Saturnian system, confirmed the existence of a subsurface ocean of liquid water on Enceladus. By analyzing samples from plumes of ice grains and water vapor erupting from cracks in the moon’s icy surface, Cassini provided crucial insights.

Dr. Glein expressed his awe at the continuous revelations about this extraordinary moon, stating, “Enceladus is one of the most dynamic objects in the solar system and is a prime target in humanity’s search for life beyond Earth.” These recent observations with the Webb’s Near InfraRed Spectrograph have once again delivered astonishing results.

Geronimo Villanueva, the lead author of the paper and a researcher at NASA’s Goddard Space Flight Center, shared his initial reaction, saying, “When I was looking at the data, at first, I was thinking I had to be wrong, it was just so shocking to map a plume more than 20 times the diameter of the moon. The plume extends far beyond what we could have imagined.”

The sensitivity of the Webb telescope has unveiled a new narrative about Enceladus and its role in providing water to the entire Saturnian system, including its rings. As Enceladus orbits the gas giant in just 33 hours, it ejects water, leaving a halo-like trail resembling a donut. Notably, the plume not only spans a vast distance but also extends into Saturn’s dense E-ring. JWST data reveals that approximately 30 percent of the water remains in the moon’s wake, while the remaining 70 percent escapes to supply the rest of the Saturnian system.

Dr. Silvia Protopapa, an expert in compositional analysis of icy bodies in the solar system from SwRI, commented on the visual representation provided by Webb’s observations. She stated, “The Webb observations, for the first time, are visually illustrating how the moon’s water vapor plumes are playing a role in the formation of the torus. This serves as a stunning testament to Webb’s extraordinary abilities. I’m thrilled to be part of the Cycle 2 team as we initiate our search for new indications of habitability and plume activity on Enceladus.”

Motivated by the groundbreaking findings from Webb’s initial glimpse of Enceladus, Dr. Glein is leading the same team for future observations using the JWST in the coming year.

“We will search for specific indicators of habitability, such as organic signatures and hydrogen peroxide,” Dr. Glein explained. “Hydrogen peroxide is particularly interesting because it can provide much more potent sources of metabolic energy than what we previously identified. Cassini didn’t give us a clear answer on the availability of such strong oxidants on Enceladus.”

The forthcoming observations will provide an enhanced opportunity to search for habitability indicators on the moon’s surface by significantly improving the signal-to-noise ratio compared to Cycle 1. Understanding the variability of plume outgassing over time is crucial for planning future planetary science missions targeting the plume.

“Webb can serve as a bridge between Cassini and the proposed search-for-life mission, Orbilander,” Dr. Glein remarked. “After Cycle 2, we will have a better idea if ocean samples are widely distributed over Enceladus’s surface, as opposed to just near the south pole. These next observations could help us determine if Orbilander can access ocean samples near the equator, which may help us get back to Enceladus sooner.”

Reference: “JWST molecular mapping and characterization of Enceladus’ water plume feeding its torus” by G. L. Villanueva, H. B. Hammel, S. N. Milam, V. Kofman, S. Faggi, C. R. Glein, R. Cartwright, L. Roth, K. P. Hand, L. Paganini, J. Spencer, J. Stansberry, B. Holler, N. Rowe-Gurney, S. Protopapa, G. Strazzulla, G. Liuzzi, G. Cruz-Mermy, M. El Moutamid, M. Hedman, and K. Denny, 19 June 2023, Nature Astronomy. DOI: 10.1038/s41550-023-02009-6

Frequently Asked Questions (FAQs) about Enceladus

More about Enceladus

• NASA’s James Webb Space Telescope (JWST) – Official website for the James Webb Space Telescope, providing information about its mission and capabilities.
• Enceladus: In Depth – NASA’s overview of Enceladus, including its characteristics and scientific discoveries.
• Cassini-Huygens Mission – NASA’s official page on the Cassini-Huygens mission, which extensively studied Saturn and its moons, including Enceladus.
• Nature Astronomy Journal – The official journal where the research paper about the water plume discovery on Enceladus was accepted and published.