NASA lab experiments have recreated the surface of Europa, one of Jupiter’s four large moons. These experiments showed that a celestial body glows in the dark. Scientists usually see Europa’s side facing the Earth, but new research has shown what a celestial body might look like from the other side.
Researchers have found that Europa’s icy surface is rich in salt, including magnesium sulfate and sodium chloride (table salt). Each type of mineral emits specific wavelengths of light when energy is released. These studies have shown that salts within the moon’s icy crust can glow in the dark. Moreover, Europe contains a huge ocean under its frozen surface.
Europa’s ice shell is between 15 and 25 km thick and floats in the ocean at a depth of 60 to 150 km. Europe is only a quarter of the Earth’s diameter, and its oceans can contain twice as much water as all of Earth’s oceans combined.
The forces of gravity between Europa, Jupiter, and its moons create cracks in the frozen surface. In some places, the ocean rises through these cracks in the ice. Therefore, by studying the ice’s outer surface, one can learn about the hidden oceans of Europe. Jupiter’s radiation raises salt molecules’ energy level as the Moon makes its way through the planetary system. When these molecules relax, energy is released as visible light.
“These high-energy charged particles, including electrons, interact with the salt-rich surface, leading to complex physical and chemical processes,” the scientists note. Europa’s surface glows green, blue, and white, depending on the salts’ types that emit the light.