Saving Voyager: NASA's Race Against Time in Interstellar Space.

NASA's Voyager spacecraft, which are the oldest running and farthest flung machines of humanity, are still going strong in interstellar space thanks to the ingenuity of scientists operating them from the ground. The spacecraft are equipped with Radioisotope Thermoelectric Generators (RTGs) that generate electrical power from the decay of Plutonium-238. As the available power declines, NASA scientists have had to come up with creative solutions to keep Voyager 1 and 2 in action, including cutting power to heating systems and allowing the craft to dip into reserve power meant to protect it from voltage spikes. Scientists are hopeful that Voyager 1 and 2 will keep sending back valuable scientific data well beyond their 50th birthdays.