March 13, 2015 at 01:50There is an ocean on Ganymede
Just a day later, as we learned about hydrothermal activity at the bottom of the subsurface ocean of the Saturn satellite, NASA announced the confirmation of a long-standing theory of the existence of the ocean on Ganymede, the satellite of Jupiter and the largest satellite of the solar system. Ganymede is almost as large as Mars and it is the only moon in the solar system with its own magnetic field. This field is created by a molten iron core, just as it happens on Earth. And the subtle atmosphere of the moon is rich in oxygen.
The Voyagers data in the 1970s became the basis of the hypothesis of the existence of the ocean on Ganymede. Then the Galileo spacecraft, which has been studying the Jupiter system since 1995, discovered the Ganymede magnetic field, confirmed the theory of the presence of an ocean of liquid water below the surface of Europe, but could not reliably confirm the presence of liquid water in the bowels of the Ganymede - there was ambiguity in the data obtained.
The theory of the presence of an ocean of liquid water beneath the surface of Ganymede was only recently confirmed with the Hubble Space Telescope. Ganymede's observations were carried out for several hours, most of this time was spent studying the auroras observed in the subtlest atmosphere of the moon of Jupiter. In the absence of the ocean, the aurora should shift approximately ± 6 degrees around Ganymede's circumference as it moves in orbit around Jupiter. In the presence of a salty electrically conductive ocean, the auroras should be stable - the shift should be about 2 degrees.
Hubble observations finally proved the existence of the ocean. The ocean is most likely located at a depth of about 100 kilometers below the surface and it is unlikely that it will be accessible for research by automatic stations.
So far, there is no reason to believe that there is hydrothermal activity at the bottom of the subsurface Ganymede ocean. And it means that the probability of the existence of life on Ganymede is small. Scientists previously suggested that the water beneath the surface of Ganymede is present as a mixture of ice and salt water.
Nevertheless, the European Agency plans in 2022 to launch the JUICE spacecraft , which will reach the Jupiter system in 2030 and will conduct research on Jupiter and its largest satellites Ganymede, Callisto and Europe for at least three years.
The Voyagers data in the 1970s became the basis of the hypothesis of the existence of the ocean on Ganymede. Then the Galileo spacecraft, which has been studying the Jupiter system since 1995, discovered the Ganymede magnetic field, confirmed the theory of the presence of an ocean of liquid water below the surface of Europe, but could not reliably confirm the presence of liquid water in the bowels of the Ganymede - there was ambiguity in the data obtained.
The theory of the presence of an ocean of liquid water beneath the surface of Ganymede was only recently confirmed with the Hubble Space Telescope. Ganymede's observations were carried out for several hours, most of this time was spent studying the auroras observed in the subtlest atmosphere of the moon of Jupiter. In the absence of the ocean, the aurora should shift approximately ± 6 degrees around Ganymede's circumference as it moves in orbit around Jupiter. In the presence of a salty electrically conductive ocean, the auroras should be stable - the shift should be about 2 degrees.
Hubble observations finally proved the existence of the ocean. The ocean is most likely located at a depth of about 100 kilometers below the surface and it is unlikely that it will be accessible for research by automatic stations.
So far, there is no reason to believe that there is hydrothermal activity at the bottom of the subsurface Ganymede ocean. And it means that the probability of the existence of life on Ganymede is small. Scientists previously suggested that the water beneath the surface of Ganymede is present as a mixture of ice and salt water.
Nevertheless, the European Agency plans in 2022 to launch the JUICE spacecraft , which will reach the Jupiter system in 2030 and will conduct research on Jupiter and its largest satellites Ganymede, Callisto and Europe for at least three years.