2007 also saw ULA's first two interplanetary spacecraft launches using the Delta II; the "Phoenix" probe was launched to Mars in August 2007 and the "Dawn" satellite to was launched to the asteroids Vesta and Ceres in September 2007. Using a Delta II, the "WorldView-1" satellite was also launched into a low Earth orbit on behalf of DigitalGlobe. The company's first launch to geostationary transfer orbit using an Atlas V 421 variant carrying the USA-195 (or WGS-1) communications satellite also occurred that year. ULA's tenth mission was launching satellite GPS IIR-17 into medium Earth orbit on a Delta II. The company completed its first Delta IV launch using the Delta IV Heavy rocket to place a payload into geosynchronous orbit in November 2007, which was followed by three more launches in December 2007.