Voyager 1 is a space probe launched by NASA on September 5, 1977. Part of the Voyager program to study the outer Solar System, Voyager 1 was launched 16 days after its twin, Voyager 2. Having operated for 41 years, 11 months and 12 days as of August 17th 2019, the spacecraft still communicates with the Deep Space Network to receive routine commands and to transmit data to Earth. At a distance of 146. 2 AU (21. 9 billion km; 13. 6 billion mi) from Earth as of August 17, 2019, it is the most distant man-made object from Earth.