[yreg]

> An icy surface may have crevasses and such and you could potentially immediately lose your probe.

I wonder, would it be viable to send multiple probes? What cost effect would it have on the mission to build and launch an extra one?

I know that e.g. for the Curiosity mission they've built a second rover that they've kept on Earth for potential troubleshooting. How much more expensive would it be to build yet another one and launch two of them?