Half of Europe lies under a thin veil of water vapor.
And NASA’s Hubble Space Telescope data shows that Europe has a long-term and permanent presence of water vapor above its surface, according to a recent study published in the journal Letters for geophysical research.
Strangely, it is present in only one hemisphere. But, in addition to bringing us one step closer to finding life in Europe, this information could have a significant impact on NASA’s upcoming missions in Europe and the search for life in extraterrestrial worlds.
The level of water vapor in Europe surprised scientists
Europe hides a colossal ocean beneath its icy shell, which may show signs of local life. If it’s there, we’ll see, but we have really good reasons to believe it is likely. But even if there is nothing alive in Europe’s oceans, knowledge of them has improved astronomers’ understanding of the atmospheric structure of ice moons in the universe and paved the way for future scientific missions to Jupiter designed to look for signs of life in the Jupiter system, along with other things. Water vapor has been seen in Europe before, but it has usually been associated with extravagant jets pouring through the lunar ice, which Hubble took in a photo from 2013. The earth has many such geysers, but those in Europe extend to more than 60 miles. And these geysers create short-lived spots of water vapor in the moon’s atmosphere, which generate only a billionth of the surface pressure on the earth’s atmosphere. But the new results reveal similar amounts of water vapor, but spread over a much wider area of Europe, according to Hubble observations from 1999 to 2015. This means that the Ionian Moon maintains a long-term atmosphere of water vapor, but only Europe’s rear hemisphere. or half of it, which is on the opposite side of the direction of the orbit of the icy body of the host planet, Jupiter.
The discovery came from a new analysis of Hubble’s database of archival spectra and images, thanks to a new technique that also recently discovered water vapor in the atmosphere of Jupiter’s other moon, Ganymede. The study was conducted by Lorenz Roth, the Swedish Royal Institute of Technology KTH, the Department of Space and Plasma Physics. “Observing Ganymede’s water vapor and from the back of Europe improves our understanding of the atmosphere of the icy moons,” Roth said in press release. “However, the discovery of a stable water abundance in Europe is a little more surprising than in Ganymede, as Europe’s surface temperatures are lower than Ganymede’s.”
Sustainable water vapor in Europe could affect upcoming NASA missions
Europe is a relatively light shade due to the abundant ice on its surface and this reflects much more sunlight than Ganymede, which is why the surface of Europe is 60 ° F cooler than its darker sister Luna. In Europe, the days can reach high temperatures, which are unconsciously low, at -260 ° F. But even at such brain-numbing temperatures, recent observations show that water sublimes or undergoes a phase change directly from solid to steam without passing through. the liquid state. And this is happening directly from the surface of Europe, just like Ganymede.
Roth had to dive deep into Hubble’s datasets to make that discovery, dividing Europe’s ultraviolet observations from 1999, 2012, 2014 and 2015, when the moon was positioned in several orbital positions. These observations were made by the Hubble Imaging Spectrograph (STIS). And ultraviolet STIS observations allowed Roth to study the abundance of oxygen on the ice body. This is important because oxygen is one of the crucial components of water and Roth finds its consistency in the atmosphere by interpolating the strength of emissions at different wavelengths, which allows him to conclude, inductively, that there was a long-term presence of water vapor on Europe. This could have significant implications for future missions in Europe, including investigations such as NASA’s Europa Clipper, Jupiter Icy Moons Explorer (JUICE) of the European Space Agency (ESA) and others. Whether or not these probes show signs of life on Jupiter’s moons, we will certainly learn more about the evolution of Jupiter’s system, which will teach astronomers more about other Jupiter-like planets orbiting distant stars.