Jupiter’s Moon Europa Glows in the Dark. Here is What Turns it into Gas Giant's Disco Ball
Representative image | Credit: © Luca Oleastri / stock.adobe.com.
The icy, ocean-covered Europa is subjected to extreme radiation attacks. Electrons and other particles from the surface of Jupiter pummel onto Europa’s surface in a shower of high energy radiation.
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While our moon shines brightest on the full moon nights, it will fade in comparison to the irradiated glow of Jupiter’s moon, Europa. The icy, ocean-covered Europa is subjected to extreme radiation attacks. Electrons and other particles from the surface of Jupiter pummel onto Europa’s surface in a shower of high energy radiation.
While radiation is a scary word with horrific aftereffects, on Europa it has a beautifying effect as the moon glows in the dark. Of course, the moon glows, that’s how we see it. But, not truly. The moon is simply reflecting the sun’s light. But, if you have seen the radium stickers (a radioactive painted material) for kids which glow in the dark, it is pretty much the same with Europa.
The analysis comes from NASA's Jet Propulsion Laboratory in Southern California. They not only informed what the moon would look like after the radiation, but also revealed details about Europa’s icy surface composition.
The emitted glimmer of radiation differs in each salty compound. With naked eyes, most irradiated glimmer would look green and some might look blue; each with a varying brightness subject to the radiated material. However, by using a spectrometer, distinct wavelengths can help connect the “signature” reflection to the ice’s composition.
“We were able to predict that this nightside ice glow could provide additional information on Europa's surface composition. How that composition varies could give us clues about whether Europa harbours conditions suitable for life,” said lead author, Murthy Gudipati. The study has been published in Nature Astronomy.
Beneath the icy surface of Europa lies massive interior oceans. Analysing the surface composition might help infer what lies beneath. Previously, the surface was known to contain ice and common salts like sodium chloride (table salt) and magnesium sulfate (Epsom salt). As the radiation penetrates through this surface, it energizes the molecules underneath. As they relax, they release the energy as light.
However, the study revealed something beyond this common understanding. Each type of ice was found to have a different visible spectrum. They built a simulator to further study this phenomenon. Ice Chamber for Europa's High-Energy Electron and Radiation Environment Testing (ICE-HEART) was built.
When they irradiated it at a high-energy electron beam facility in Gaithersburg, Maryland, they wanted to see how organic matter underneath the icy surface might react to radiation. They discovered instead that icy bands reflect differently.
NASA’s flagship mission Europa Clipper will launch in a few years. It will be observing the moon’s surface with a few flybys. The researchers would then be able to see if their hypothesis (Europa is perennially glowing in the dark) true to what limit and how accurate their salt-composition result is.