Europa's orbit is an ellipse, and the satellite's shape is affected by Jupiter's gravity, becoming deformed when it passes closer to Jupiter. This change in shape creates friction inside Europa, generating enormous amounts of heat in a mechanism known as tidal heating, which melts some of the ice and forms a vast internal ocean beneath the moon's thick ice shell. Europa's internal ocean is salty and is estimated to be about 100 kilometers deep on average, with a total volume of water twice that of all Earth's oceans, despite this moon being considerably smaller than our planet. In addition, it is believed that internal oceans exist on Jupiter's moons Ganymede and Callisto and Saturn's moons Titan and Enceladus. Liquid water is essential for life as we know it, which is why the ocean worlds are at the forefront of the search for extraterrestrial life.

Artificial intelligence will help scientists search for signs of ancient life on Mars and other planets thanks to work by NASA scientists in training the system. The European Space Agency (ESA) Rosalind Franklin'ExoMars' rover will be the first to have the new AI system when it leaves for the Red Planet in 2022/2023. Allowing these intelligent systems to choose both what to analyse and what to tell us back on Earth will overcome severe limits on how information is transmitted over huge distances in the search for life from distant planets. The system is being tested on Mars but has been designed to be used in future missions to the icy moons of Jupiter and Saturn where distance is more of an issue. The European Space Agency (ESA) Rosalind Franklin'ExoMars' rover will be the first to have the new AI system when it leaves for the Red Planet in 2022/2023 Presenting the work at the Goldschmidt Geochemistry conference, lead researcher Victoria Da Poian from NASA said this was a'visionary step in space exploration'.

Artificial intelligence could help in our hunt for extraterrestrial intelligence. The moons of Jupiter and Saturn are two of our most promising leads in the hunt for alien life, but they're hundreds of millions of miles from Earth. Given the high cost of transporting payloads in space, NASA is currently in search of anything that could help decrease the weight of exploratory landers -- and AI is proving it might be up to the task. On Tuesday, engineers from NASA's Jet Propulsion Laboratory and software company Autodesk unveiled a lander designed to explore environments like those of Jupiter and Saturn's moons. The team developed the lander, which looks a bit like a spider that's missing half its legs, using a technique known as generative design.

Forty years ago, NASA launched twin robotic explorers on a mission to travel farther out than any spacecraft had gone before, and today, they continue to be our most distant emissaries. The story of those probes, and of the people behind them, is the focus of the aptly-titled documentary, "The Farthest," airing Wednesday (Aug. The Voyager probes, referred to by numerical designators "1" and "2," revealed the outer planets of our solar system and then continued to sail beyond. Voyager 2, which was the first to launch on Aug. 20, 1977, visited Jupiter, Saturn, Uranus and Neptune. Voyager 1 departed Earth on Sep. 5, 1977, overtook its counterpart, and was the first to arrive at Jupiter and Saturn.