If you were designing the JWST today, you would probably also put onboard a GPU. That could be programmed to do some of the scientific work in space to reduce the amount of data that needs to be downloaded.<p>This would allow new types of science (for example, far shorter exposure times and stacking to do super resolution and get rid of vibrations in the spacecraft structure). It would also allow redundancy incase the data downlink malfunctions or is degraded - you can still get lots of useful results back over a much smaller engineering link if you have preprocessed the data.<p>Obviously, if that GPU malfunctions, or there isn't sufficient power or cooling for it due to other failures, data can still be directly downloaded as it is today.<p>Basicly, it adds a lot of flexibility.