Smaller, multiple satellite missions are economical and provide redundancy. Instead of launching one big, heavy satellite, launching lots of little is easier. They can orbit Earth in tandem, each doing their own small part of the overall mission. If a solar flare zaps one satellite—no problem. The rest can close ranks and carry on. Launch costs are reduced, too, because tiny satellites can hitch a ride inside larger payloads, getting to space almost free of charge.