NASA’s Hubble spots Underground Ocean on Jupiter Moon Ganymede

There could be life on the largest Jupiter moon. A salt water ocean has been identified by NASA on Ganymede.

Humanity is on the hunt for signs of life in the universe since decades, but no luck so far. There is a new potential place where there could be extraterrestrial life. NASA said in a new report that the Hubble Space Telescope has the best evidence yet for an underground saltwater ocean on Ganymede, Jupiter’s largest moon.

The Ganymede ocean is considered to be huge. According to NASA it has more water than all the water on Earth’s surface.

“This discovery marks a significant milestone, highlighting what only Hubble can accomplish,” said John Grunsfeld, associate administrator of NASA’s Science Mission Directorate at NASA Headquarters, Washington. “In its 25 years in orbit, Hubble has made many scientific discoveries in our own solar system. A deep ocean under the icy crust of Ganymede opens up further exciting possibilities for life beyond Earth.”

Ganymede is the largest moon in our solar system and the only moon with its own magnetic field. The magnetic field causes aurorae, which are ribbons of glowing, hot electrified gas, in regions circling the north and south poles of the moon. Because Ganymede is close to Jupiter, it is also embedded in Jupiter’s magnetic field. When Jupiter’s magnetic field changes, the aurorae on Ganymede also change, “rocking” back and forth.

Scientists observed this rocking motion of the two aurorae and determined that a large amount of saltwater is under the Ganymede surface affecting the magnetic field.

The image above shows NASA Hubble Space Telescope images of Ganymede’s auroral belts (colored blue) that are overlaid on a Galileo orbiter image of the moon.

A team of scientists led by Joachim Saur of the University of Cologne in Germany came up with the idea of using Hubble to learn more about the inside of the moon.

“I was always brainstorming how we could use a telescope in other ways,” said Saur. “Is there a way you could use a telescope to look inside a planetary body? Then I thought, the aurorae! Because aurorae are controlled by the magnetic field, if you observe the aurorae in an appropriate way, you learn something about the magnetic field. If you know the magnetic field, then you know something about the moon’s interior.”

The scientists estimate the ocean is 60 miles (100 kilometers) thick – 10 times deeper than Earth’s oceans – and is buried under a 95-mile (150-kilometer) crust of mostly ice.

The NASA Hubble Space Telescope is celebrating 25 years of operation on April 24.  Hubble is a project of international cooperation between NASA and ESA (European Space Agency). NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, Inc., in Washington.