Steamed Ganymede

After we talked about receiving ‘Visit’ from the probe Juno From NASA7th of last June, Ganymede – Luna D Jupiter Returns to the forefront of study on his site موقع AtmosphereIt was just posted on natural astronomy (Element: “Transcendental Hydrosphere on Ganymede Discovered from Hubble Space Telescope Observations”). The survey that highlights the presence of Water vapor in the atmosphere One of the largest natural satellites in the world Jupiter, by an international working group, coordinated by Royal Institute of Technology Stockholm, and was based on data from Hubble, recent and archival.

Previous research found that Ganymede, which is also the largest moon in the entire solar system, contains more Water from all terrestrial oceans. liquid in addition to being frozen Because of the extremely cold temperatures, it is hidden about 160 kilometers under the crust of an orb, and therefore cannot be subject to evaporation. Therefore Water vapor Found thanks to the historic NASA-ESA telescope must have another Source.

Scientists examined data collected by Hubble over the past twenty years. in a 1998 his tool Stace (sa step Ttelescope IHe is spectrograph) first pictures of Ganymede NileUltravioletThis highlights the presence of both auroral bands that from Weak magnetic field. the Similarity Found in these observations in ultraviolet radiation was traced back to the existence of molecular oxygen (O2); However, they appeared later some characteristics Not attributable to emissions from the atmosphere consisting of pure O2. At the time, scientists speculated that this discrepancy might be due to higher concentrations of atomic oxygen (s).

under wide Notes program Designed to support investigative activity JunoThe authors of the article chose me data archiving From Hubble and merge them with those collected in 2018 from another telescope instrument, cos (NSosmotic NSstrictness spectrograph). Their intention was to carry out new measurements Delatomic oxygen in the air Ganymede: However, in contrast to a 1998 study, this element was almost absent. At this point, the team had to work Interpreting the differences Among the old observations in ultraviolet light focused on Twilight Distribution, indicating that temperature from the surface Ganymede It varies greatly throughout the day, at noon and near the equator hot enough because ice Releases small amounts of water molecules. Thus, the differences in the above images are directly related to where one would expect to find water in the lunar atmosphere. This discovery, according to the working group, could be very useful as a base For the future Expedition juice Delwho – which, which was created specifically for the study Icy moons of Jupiter Which is scheduled to be launched in 2022.

Juno, who “celebrated” on the 4th of July last five years of scientific activity in orbit Jupiter, To understandthe origin and thehas evolved from the planet. mission, byItalian space agency, is proud of the great contribution of our country with the spectrometer jiram (instrumentInaf-Iaps, known as Leonardo) and radio science tool ka t (Translator Ka Band, DilUniversity of “La Sapienza” From Rome, who made Thales Alenia Space Italy).

Above: Ultraviolet images of Ganymede (Credits: NASA, ESA, El Roth – Keith) – in Bottom: Ganymede’s internal structure (credits: NASA – Goddard Space Flight Center).