Ever since the House passed a NASA spending bill that allocated $100 million for a probe to Jupiter’s moon Europa, the space agency has been attempting to find a way to do such a mission on the cheap. The trick is that the mission has to cost less than $1 billion, a tall order for anything headed to the Outer Planets. According to a Wednesday story in the Atlantic, some researchers at Draper Labs have come up with a cheap way to do a Europa orbiter and land instruments on its icy surface.
The first stage is to orbit a cubesat, a tiny, coffee can sized satellite that would contain two highly accurate accelerometers that would go into orbit around Europa and measure its gravity field. In this way the location of Europa’s subsurface oceans would be mapped. Indeed it is possible that the probe might find an opening through the ice crust to the ocean, warmed it is thought by tidal forces.
The second stage is to deploy even smaller probes called chipsats, tiny devices that contain sensors, a microchip, and an antenna. Hundreds of these probes, the size of human fingernails, would float down on Europa’s atmosphere to be scattered about its surface. While some might be lost, enough will land over a wide enough area to do an extensive chemical analysis of the surface of Europa, which would then be transmitted to the cubesat mothership and then beamed to Earth.
This mission architecture has its limitations. Chipsats would not return images from the surface of Europa, something that would not only have scientific significance but would look good on coffee table books. But so long as NASA’s budget remains flat, the Draper Lab idea is likely going to be the only way we are going to have a close examination of Europa or any of the other moons of the outer planets such as Titan.