Near the end of the twentieth century, we began launching unmanned probes into the far reaches of the solar system. What they discovered was amazing and in some cases unexpected. Now after dozens of probes have been deployed, the exploration continues. New space missions are underway, and many of these robust spacecraft are still operational, beaming their knowledge back to Earth every day. We will pay tribute to these robots who have explored in our place and experience what they have taught us about our solar system.