Researchers from the University of California said that magnetometer readings measured by the Galileo research satellite showed the presence of a large body of water beneath the icy surface of the moon.
Avi Blizovsky
New findings from a spacecraft orbiting the region of the planet Jupiter reveal that one of the planet's moons, Ganymede, probably has a large ocean of salt water. Researchers at Brown University in the USA analyzed findings sent by the Galileo spacecraft six months ago, when it was closest to Ganymede. From the findings it seems that about 150 kilometers below the surface of this moon of Jupiter, there is a very large amount of salt water. They say that this situation is very similar to what happens on two other moons of Jupiter, Callisto and Europa.
Scientists from California: We found evidence for the existence of an ocean on one of Jupiter's moons
Scientists have said that evidence has been found that in one of the largest moons of the planet Jupiter, Ganymede, there is an ocean of water - a key component for the existence of life.
The researchers, working at the University of California, said today (Sunday) that magnet readings measured by the research satellite "Galileo" showed the presence of a large body of water beneath the frozen surface of the moon. Wherever there is water on earth there is also life. This is not necessarily true in space, but this discovery raises expectations that one day the existence of life in outer space will be proven. Ganymede is the third moon of Jupiter to show signs of water beneath its icy surface.
The researchers also said that they cannot be sure that water has indeed been discovered on Ganymede - which is a larger moon than Mercury or Pluto. The person in charge of the study, Margaret Kibleson, said that the findings look "quite convincing". Kielson will present the findings today at the fall meeting of the American Geophysical Union in San Francisco.
Other scientists have identified salty minerals on Ganymede's crust. The finding of the minerals indicates that salty water was once found on the lunar surface. "The findings are similar to the salty minerals found on the moon Europa, probably as a result of salt water that reached the surface through eruptions or through cracks," said Thomas McCord, a geophysicist from the University of Hawaii. The assumption of the existence of water on Ganymede is supported by high-quality images that came from the Galileo satellite.
In 1998, Dr. Kibbleson and her colleagues looked for evidence of their placement, by observing the changes in direction and strength of Jupiter's magnetic field every time Galileo, in its satellite orbit around Jupiter, passed by the moon Europa. The moon, the researchers said, generated electric currents as it flowed through Jupiter's powerful field.
The new electric currents generated magnetic fields that changed Jupiter's field. For an electric current to flow on Europa, some part of Europa must conduct electricity, and ice is not a good conductor. Liquid salt water, on the other hand, conducts well. The fluctuations in the electric field therefore pointed to an ocean located at a distance of about eight to 16 kilometers below the surface. The new findings, based on data from two Galileo visits to Ganymede in 1996 and May 2000, found similar magnetic fluctuations.
