Is there life “out there?” If there is, it may be on one of the four largest moons orbiting Jupiter – and an Israeli-developed atomic clock technology-based device will ferret out signals of that life, should there be any. The device in question was developed by Israeli firm AccuBeat, working with the Weizmann Institute’s Dr. Yohai Kaspi, Israel’s lead investigator, in collaboration with the University of Rome, on the 3GM (Gravity & Geophysics of Jupiter and Galilean Moons) Project, a part of the European Space Agency’s JUICE mission.
JUICE, the JUpiter ICy satellite Explorer, is likely to lift off sometime at the beginning of the next decade, and by 2030 should reach Jupiter, where it will take measurements of the biggest planet in the solar system, along with data from the biggest of Jupiter’s 67 known moons – Io, Ganymede, Europa, and Callisto, known as the Galilean moons (for Galileo, who discovered them with his telescope).
Astronomers for centuries have been especially interested in the Galilean moons, because of their topography, geology, size, orbit, and other factors. Most interesting is the likelihood, many scientists believe, that at least three of the four moons harbor underground oceans.
Where there is water, life may – or perhaps is even likely to – follow. Among JUICE’s mission will be to determine once and for all if there is water under the surface of these worlds. And the 3GM project, which Israel is participating in, is the key to making that determination. The Israeli contribution to the project is an atomic clock-based device that will measure tiny vacillations in a radio beam provided by the Italian team.
During the approximately two and a half years that JUICE orbits Jupiter, the 3GM team will investigate the planet’s atmosphere by intercepting radio waves traveling through its gas atmosphere, timing them and measuring the angle at which the waves are deflected. This will enable them to decipher eactly which gasses make up Jupiter’s atmosphere.
But on flybys of three of the planet’s moons – Europa, Ganymede and Callisto – the 3GM instruments will help search for tides, which, if water exists under the moons’ surfaces, are likely to be present. Scientists have measured fluctuations in the gravity of the moons, suggesting that Jupiter is exerting a magnetic pull on them. By measuring those variations in gravity, the researchers hope to learn how large these oceans are, what they are made of, and even whether their conditions might harbor life.
To do that, the team has adopted AccuBeat’s atomic clock technology to build the world’s most accurate ever Ultra Stable Quartz Oscillator (USO). Oscillators, of course, can be used to measure fluctuations in radio waves, and the USO will measure variations in a radio wave beamed by the Italian team at the moons’ surfaces. Variations in that wave will indicate that something is “moving” on the surfaces – or below them.
On the assumption that those somethings are tides, the signals will indicate how much the water is being displaced, and whether that displacement is uniform in size and duration. If it is not, it could mean that something is in the water – a microbe, or even something bigger – is said the team.
Besides having a chance to explore one of the biggest mysteries in the solar system, Israel has an opportunity to send its tech further than it has ever gone. “This is the first time that an Israeli-built device will be carried beyond the Earth’s orbit,” said Kaspi, who along with colleagues Dr. Eli Galanti and Dr. Marzia Parisi, spent the last two years in research and development to design, together with AccuBeat, a device that should not only meet the strict demands of the experiment but survive the eight-year trip and function in the conditions of space. Their design was recently approved for flight by the European Space Agency. Israel’s Ministry of Science and Technology will fund the research, building and assembly of the device.
The JUICE teams are preparing for a launch in 2022. That gives them three years to get the various instruments ready and another three to assemble and test the craft. In the long wait – eight years – from launch to arrival, Kaspi intends to work on building theoretical models that can be tested against the data they will receive from their instruments, the Weizmann team said.