Another new member has been added to the fleet of U.S. spy satellites in space. On Friday, a Delta IV medium rocket of ULA (United Launch Alliance) carrying the top-secret spy satellite payload blasted off from Vandenberg Air Force Base, California at 5:11 p.m. EST (2211 GMT, 2:11 p.m. local time). The name of the spy satellite is NROL-47, and it is a classified mission. As per Space.com, the National Reconnaissance Office (NRO), which builds and manages the spy satellites of the U.S., will operate the new classified NROL-47 satellite. As usual, no one knows what the NROL-47 satellite is all about and what its mission is.

The latest spy satellite mission was ULA’s fits flight of 2018, and also it was the 27th successful mission of ULA for the NRO. Also, the Friday’s mission marked the 36th flight of ULA’s Delta IV rocket. Will Crawford, ULA’s NRO program manager, said, “As the nation’s most trustworthy launch provider, today’s launch exemplifies ULA’s ongoing commitment to 100 percent mission success.” He also thanked the entire ULA team as well as the mission partners at the NRO and also the U.S. Airforce for making the 27th NRO launch a successful one.

Last year, ULA launched three NRO satellites atop Atlas V rockets. But this time, it has used the two-stage, 217-foot-tall (66 m) Delta IV rocket. The rocket is a “5, 2” variant and it featured a 5-meter-wide (16.5 feet) payload fairing, as reported by Space.com. Back in December 2017, Spaceflight Now’s Stephen Clark had informed that “5, 2” variant Delta IV rocket had previously flown twice- in 2012 and 2016- and carried Topaz radar reconnaissance satellites into orbit.

The Friday launch of the spy satellite occurred after a two days delay, first due to strong ground winds and then due to an issue with a ground system valve. Five days before the classified NROL-47 launch, SpaceX had launched a top-secret Zuma payload for the US government. The Zuma mission is speculated to be failed mission but what happened exactly is still unclear. But ULA has announced that Friday’s NRO spy satellite launch is a success, and the payload has been successfully deployed into the orbit. The National Reconnaissance Office is a U.S. Government agency which has been given the charge to design, build and launch and maintain America’s fleet of spy satellites.