Costing $895 million for the two Voyager spacecraft, Voyager 1 is expected to be able to report for another 11 years which would put it at a distance of about 15 billion miles from Earth/Sun. Assuming a similar lifespan for Voyager 2, at that same time it will be about 13 billion miles. So a total reporting mileage of 28 billion at $895 million works out to a cost of about $0.03/mile. This may be the best bargain that the Federal Government has gotten to date!
It is.
The future belongs to unmanned spacecraft. They have gone and will go where no man can. In fact man might not be able to match these accomplishments for probably thousands or more years, or possible never.
Unmanned spacecraft have obtained so much data in the past 30 plus years, we'll be studying that data for another several decades. It will be the unmanned spacecraft which will pave the way manned missions and is in fact doing that right now in regards to Mars.
It's why the Shuttle program needed to end...I believe the shuttle program competed about 30,000 orbits...It basically was reduced to supplying the ISS.