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Draper Labs Develops Low Cost Probe To Orbit, Land On Europa For NASA
MarkWhittington writes 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.
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.
Gee, I guess the engineers at NASA don't know about radiation levels at Jupiter. Lucky for them you posted about it on the internets. I'll forward them your post so they aren't left in the dark.
Actually, OP is completely correct. I just sat in on a series of NASA talks on cubesats (NEPP, look it up) - they have huge problems with radiation and reliability because there isn't the budget for the testing and qualification that happens with typical satellites. Translation: 30% failure rate in benign environments. For reference, we're talking about systems that are (mostly) good up to 1-4 krads of ionizing dose, while projections I've seen for the Europa environment are ~ 2 Mrads. Or 2000 krads, if your metric is rusty. So we're talking about as much as 3 orders of magnitude more dose, with a system architecture that already experiences horrendous failure rates.
I don't know anything about Draper systems, but unless they've included mass budget for some serious shielding (look up JUNO and the "vault" they used for their electronics) there's no way this thing will last long enough to do useful science, if it even survives the trip there. It's entirely possible that this entire thing is the brainchild of a couple of postdocs who took some classes on spacecraft architectures but no nothing about how rad-hard electronic systems are actually developed.
Now, it's certainly possible that this project would be in a different class of cubesat, and they might be able to afford real, rad-hard components with Mrad range dose tolerance, but even so, Jupiter is one of the harshest radiation environments in the solar system, and satellites with traditional, expensive development cycles still have mission lifetimes of several months, tops. The only real way I could see them being successful is with rad-hard components and an extremely short mission profile - show up, dump the chipsats, and beam back some data as fast as possible before your electronics go insane and melt.