NASA Wants to Explore the Icy Moons of Jupiter and Saturn With Autonomous Robots

Europa’s orbit is elliptical, and the moon’s shape is influenced by Jupiter’s gravity, distorting as it approaches Jupiter.

This change in shape causes friction within Europa, which generates a large amount of heat in a process known as tidal heating, which melts some of the ice and creates a vast internal ocean beneath the moon’s dense icy shell.

Europa’s interior ocean is salty, and although this moon is considerably smaller than our planet, it is estimated to be about 100 km deep on average, with twice as much water as all of Earth’s oceans.

A comparison of Earth’s oceans and Europa’s inland oceans.

Example: NASA/JPL-Caltech

Also, it is believed that Jupiter’s moons Ganymede and Callisto and Saturn’s moons Titan and Enceladus have internal oceans.

Liquid water is essential to life as we know it, which is why ocean worlds are leading the search for extraterrestrial life

The European Space Agency’s Jupiter Ice Explorer is a spacecraft that will be used to explore Jupiter’s ice caps.

Image: ESA/m. Pedosat

under the sea (ice)

The autonomous underwater exploration robots envisioned by SWIM are extremely small. Their wedge-shaped body is about 12 cm long. A device called a “cryobot” will transport robots beneath the moon’s thick ice shell, using nuclear energy to melt the ice. The idea is to pack about four dozen robots into cryobots and encase them in a thick ice shell for several years.

A conceptual drawing of SWIM with the cylindrical probe in the upper left corner.

Image: Ethan Schaller/NASA/JPL-Caltech

There are advantages to sending such a large number of search robots. One is that they can explore a wider area. Another is that they are envisioned to work in teams, so that multiple robots can explore the same area in overlapping directions, reducing errors in observation data.

Each robot will be equipped with sensors to measure the temperature, pressure, acidity, electrical conductivity and chemical composition of the water it explores. All these sensors will be mounted on a chip measuring just a few millimeters square.

“People might ask, why is NASA building an underwater robot for space exploration?” Ethan Schaller, project leader at NASA JPL, explained the motivation behind SWIM. “Because there are places in the solar system where we want to look for life — and we think life needs liquid water.”

This story originally appeared wired Japan and translated from the Japanese.