JWST Discovers Enceladus's Geyser Plume Is Much Bigger Than We Thought

In fact, scientists admitted at a symposium that Cassini missed the full scope of Enceladus's water plume, despite the spacecraft detecting the largest one yet.

Enceladus, Saturn's moon, shot to the top of planetary scientists' priority lists after geysers were found close to the moon's South Pole. Enceladus is one of six (or maybe ten) worlds in the Solar System that have seas buried behind ice crusts, and it often ejects parts of those oceans into space, some of which become a component of Saturn's E ring.

In addition to the finding Enceladus possesses all the elements required for life, at least the ones we are aware of, therefore a sample of the plumes is quite valuable. It's very feasible that the plume contains signs of biological activity, showing that the cosmos is teeming with life.

Every bit of information we can scrounge up is valuable given how long it will take until a spacecraft is prepared to gather plume samples. Recently, when the JWST directed its attention in that area, it created more than a scrap, documenting an eruption of that scale. According to Dr. Sara Faggi of the Goddard Space Flight Center, who declared at a symposium last week, "It's immense," Nature writes.

The geyser's existence was initially made known by Cassini in 2005. The probe's observations of the "tiger-stripes" near the moon's South Pole during successive fly-bys allowed scientists to recreate how material is moving from the interior ocean to the surface and beyond.

Since the geysers weren't recognized while Cassini was being constructed, their spray wasn't intended to be sampled. Even so, it was able to demonstrate the vital existence of silica particles, suggesting that the waters are sufficiently mixed to allow material from the floors to reach the cracks from whence these fountains erupt.

Cassini was unable to fully gauge the extent of the plumes since it may be challenging to get a clear view of something when you're too near to it, much alone within. The JWST enters the picture here. The space telescope showed a cloud considerably bigger than any Cassini could see, spanning much further into space than the diameter of the moon it originates from, in just 4.5 minutes of its limited time.

Dr. Faggi won't reveal any more information, instead advising readers to wait for the study, which will reportedly estimate the amount of water spilled and its temperature (a task best suited for the JWST). JWST's photos could tell something about the plume's composition, perhaps even including biosignatures, which might be much more significant. All Faggi said to Nature was, "We have many more surprises."

However, if we're going to send a mission a billion kilometers to Saturn, we'll probably want to swoop low to gather from where the material is densest. The extent of the plume makes it possible for a future mission to collect samples over a larger region. If we don't throw a robotic snake into a chasm immediately, that is. But long before then, JWST will spend six times as much time monitoring Enceladus in its second session, indicating that its schedulers believe the initial viewing was as fruitful as Faggi suggests.

According to Nature, another Goddard scientist, Dr. Geronimo Villanueva, reported the discovery of carbon dioxide on Europa at the same symposium, which also featured other significant discoveries from the original inner ocean planet.