Hubble Finds the First Traces of Water Vapor on Jupiter’s Moon, Ganymede 

For the first time, the astronomers have exposed the evidence of the presence of water vapor in the atmosphere of Jupiter’s moon Ganymede. This water vapor is formed when ice from the moon’s surface transfers — which means it turns from solid to gas.

Scientists have used new and archival data sets from the Hubble Space Telescope of NASA to publish insights in the journal called Nature Astronomy.Previously done research has offered incidental evidence that Ganymede, the largest moon in the solar system, contains more water than all of the oceans present on the Earth. However, the temperatures are so cold that the water on the surface of the moon is frozen into a hard solid.

Ganymede’s ocean would be located unevenly 100 miles below its crust – thus, the water vapor would not signify the evaporation of this ocean.Astronomers have re-examined the observations made by the Hubble from the last two decades already to find this evidence of water vapor.In 1998, Hubble Space Telescope Imaging Spectrograph or STIS took the first ultra-violet (UV) images of Ganymede, which discovered in 2 of the photos, colorful ribbons of electrified gas, called auroral bands, provided further evidence that Ganymede has a weaker magnetic field.

Right away, NASA’s Juno mission is also taking up a closer look at Ganymede, and it recently released the new imagery of the icy moon. Juno has been studying Jupiter and its environment, also known as the Jovian system, since the year 2016.