“Enceladus is giving us free samples of what’s hidden deep below.”

Saturn’s icy moon Enceladus shoots particles of frozen silica into space, and scientists might finally know why. Scientists have long known that Enceladus spewed out icy silica that eventually made its way into Saturn’s E ring, but they didn’t have a good explanation as to why this was happening.

Now, a new study by a team at the University of California Los Angeles might provide the answer. Their research shows that tidal heating in Encealadus’ rocky core creates currents that push the silica to the surface. Once there, it’s likely released into space by deep-sea hydrothermal vents.

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NASA / jpl-caltech / space science institute.

Scientists at Osaka University were part of a particle accelerator experiment that produced an exotic and highly unstable particle, and determined its mass. This could contribute to a better understanding of the inner workings of ultra-dense neutron stars.

The Standard Model of particle physics explains that most particles are made of combinations of just six types of basic entities called quarks. However, there are still many unsolved mysteries, one of which is Λ(1405), an exotic but fleeting Lambda resonance. It was previously believed to be a specific combination of three quarks – up, down, and strange – and gaining insight into its composition could assist in uncovering information about the extremely dense matter in neutron stars.

Now, investigators from Osaka University were part of a team that succeeded in synthesizing Λ(1405) for the first time by combining a K^– meson and a proton and determining its complex mass (mass and width). The K^– meson is a negatively charged particle containing a strange quark and an up antiquark.

That’s aurorae.

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Jupiter is well known for its spectacular aurorae, thanks in no small part to the Juno orbiter and recent images taken by the James Webb Space Telescope (JWST). Like Earth, these dazzling displays result from charged solar particles interacting with Jupiter’s magnetic field and atmosphere. Over the years, astronomers have also detected faint aurorae in the atmospheres of Jupiter’s largest moons (the “Galilean Moons”). These are also the result of interaction, in this case, between Jupiter’s magnetic field and particles emanating from the moons’ atmospheres.

Detecting these faint aurorae has always been a challenge because sunlight reflected from the moons’ surfaces completely washes out their light signatures. In a series of recent papers, a team led by the University of Boston and Caltech (with support from NASA) observed the Galilean Moons as they passed into Jupiter’s shadow. These observations revealed that Io, Europa, Ganymede, and Callisto all experience oxygen-aurorae in their atmospheres. Moreover, these aurorae are deep red and almost 15 times brighter than the familiar green patterns we see on Earth.

The research team included astronomers from the Center for Space Physics (CSP) at Boston University, the Division of Geological and Planetary Sciences (GPS) at Caltech, the Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado, Earth, and Planetary Science at the UC Berkeley, Large Binocular Telescope Observatory (LBT), the Southwest Research Institute (SwRI), the Planetary Science Institute (PSI), the Leibniz-Institute for Astrophysics Potsdam (AIP), and NASA’s Goddard Space Flight Center. The two studies, titled “The Optical Aurorae of Europa, Ganymede, and Callisto” and “Io’s Optical Aurorae in Jupiter’s Shadow,” appeared on February 16th in the Planetary Science Journal.