NASA's Hubble Space Telescope has gained very strong evidence that saltwater oceans are beneath the surface of Jupiter's moon Ganymede. Ganymede is one of Jupiter's largest moons. Scientists believe that the underwater ocean of Ganymede has more water than all the water here on Earth.

Scientists emphasize that finding liquid water is a crucial factor in finding life outside of our planet Earth as we know it.

This discovery represents a significant milestone in the possibilities that the Hubble Telescope can achieve. John Grunsfeld, an administrative coworker, said Science Mission Directorate at NASA Headquarters, Washington. For 25 years of its existence, Hubble has made a lot of scientific discoveries about our solar system. The deep ocean under the ice of the moon Ganymede opens up other interesting possibilities for finding life beyond our planet Earth.

Ganymede is one of the largest moons in our solar system and also the only moon with its own magnetic field. The magnetic field creates aurora borealis around the moon. It consists of bands of hot electrified gas in the southern and northern hemispheres of the moon. The moon is also affected by Jupiter's magnetic field, so as Jupiter's magnetic field changes, so does the movement of the aurora back and forth - it waves.

According to polar caliber waves, scientists have been able to determine that a large amount of salt water is just beneath the surface of the Ganymede moon, as salty water affects its magnetic field.

A team of scientists led by Joachim Saur from the University of Cologne (Germany) came up with the idea of ​​using Hubble to study what is beneath the moon's surface.

I've always been thinking aloud about how we can use the telescope in a different way, Saur said. Is there a way to use the telescope to look inside the planet? Then I had aurora borealis! Because if aurora borealis is controlled by a magnetic field, then if we examine it appropriately, we will learn something about the magnetic field. If we know something about the magnetic field, then we can judge something about the inside of the moon.

If there is a salty ocean, then Jupiter's magnetic field creates a secondary magnetic field in it. This magnetic field then acts against Jupiter's field. This magnetic friction would then explain diminished swing polar caliber on Ganymede. Ganymede's subterranean ocean fights Jupiter's magnetic field so hard that the sway of the aurora decreases to just 2 ° instead of 6 °, which it could reach if the ocean were not present.

Scientists estimate that Ganymede's ocean is a deep 100 km and therefore 10x larger than the oceans on Earth. At the same time, it is buried under 150 km with a thick bark, which is mostly made of ice.

With the first suspicion that there might be an ocean on Ganymede, scientists came back in 1970 based on models of the big moon. In 2002, NASA's Galileo spacecraft measured Ganymede's magnetic field, providing initial evidence to support the allegations. Galileo did a few concise pictures at 20 minute intervals. These observations were, however, too short to recognize the swing of the secondary magnetic field of the ocean.

New observations were made using ultraviolet radiation just by Hubble's telescope, which is high above Earth's surface. Earth's atmosphere blocks ultraviolet radiation.