Enceladus’ Massive Vapor Cloud Observed by James Webb Space Telescope

Enceladus is a seemingly insignificant icy moon of Saturn, but thanks to its salty water ocean hidden under a thick ice crust, it plays an important role in the search for traces of extraterrestrial life. From the surface, the geysers shoot high in jets of water from under the solid ice sheet. The resulting vapor clouds escape from the moon’s gravitational pull and escape into the Saturn system. Many astronomers have been waiting for this moon to be the turn of the James Webb Space Telescope (James Webb Space Telescope – JWST) in its monitoring schedule. The experts were not disappointed with the first results.

One of the interesting formations observed by JWST was a vapor cloud twenty times larger in diameter than the moon Enceladus. This more than 10,000 km phenomenon is similar in size to the size of the Earth. In addition to the fact that planetary scientists have never seen such a water release, the observation is also important because it sheds light on how material from the moon interacts with Saturn’s system, including the planet’s iconic rings.

Enceladus is only 500 km in diameter, but its structure makes it special. Wedged between the moon’s thick icy crust and rocky core is a thick, liquid ocean, whose salty water covers the entire celestial body. Geyser-like ice volcanoes shoot ice debris, water vapor, and organic matter into the air from fissures in the moon’s crust dubbed “tiger stripes.” Researchers have already observed such vapor clouds a few hundred km above the surface, but due to the extraordinary sensitivity of the JWST, a completely new story has now unfolded before our eyes.

Not only the size of the cloud, but also the intensity of the eruption is worth mentioning. 300 liters of water erupt from the geyser every second. With such a water flow, an Olympic-sized swimming pool could be filled in a few hours, while it would take weeks to do the same with a garden slag.

Enceladus orbits Saturn in just 33 hours, spewing water everywhere it goes. This essentially creates a donut-shaped vapor cloud around the planet. And this water vapor torus is none other than Saturn’s outermost and widest, dense E-ring.

Although the Saturnian system, including the vapor clouds of the Enceladus geysers, had already been observed by the Cassini spacecraft before, and even sampled their material by flying through the clouds, JWST’s point of view and precise instruments open up new possibilities for observing the system. Observations have shown that water vapor from the moon feeds the E-ring. According to calculations, 30 percent of the material from the geysers is directly integrated into the ring, while 70% of the water escapes from here and migrates to other parts of the system.

JWST’s current and future observations of Enceladus and other icy ocean moons will also help to optimally design the research programs of future probes designed for these celestial bodies, searching for possible traces of extraterrestrial life.

Source: NASA

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