A spy satellite atop an Atlas V rocket blasted off on a classified mission Saturday night from Vandenberg Air Force Base in California.
US officials have not revealed what the spacecraft will be doing or what its orbit will be.
Some have suggested it will use sensors to gather data on an enemy’s electronic defence network, including radars, surface-to-air missile systems and aircraft.
All systems were going well when a webcast of the launch of the NROL-42 satellite concluded about three minutes into the flight, which took place on Saturday, September 23.
NROL-42 is the latest in a secretive fleet of craft constructed and operated by the National Reconnaissance Office (NR0).
Very little is known about the function these particular eyes in the sky perform, but spy satellites can provide a range of services.
These include missile early warning, nuclear explosion detection, photo surveillance, electronic-reconnaissance and radar imaging.
In a prelaunch statement Air Force colonel Gregory Wood, 30th Space Wing vice commander at Vandenberg, said: This launch is the culmination of many months of work by United Launch Alliance, the National Reconnaissance Office and the 30th Space Wing.
‘All of Team Vandenberg is dedicated to mission success and proud to play a part in delivering these capabilities to our nation.’
The launch was conducted by United Launch Alliance (ULA), a joint venture of Lockheed Martin and Boeing.
It took place at the base’s Space Launch Complex-3 at 10.49 pm PDT (1.49 am ET / 6.25 am BST September 24).
Speaking after the launch Laura Maginnis, ULA vice president of government satellite launch added:’Congratulations to the entire team for overcoming multiple challenges throughout this launch campaign.
‘From Hurricane Irma schedule impacts to replacing to a first stage battery this week – the team maintained a clear focus on mission success.
NROL-42 marks the 25th ULA-launched NRO mission.
It is part of a wider campaign by the United States to ensure their dominance in space.
Part of that effort is the X-37B orbital test vehicle programme, which has seen unmanned space drones launched into orbit.
Earlier this month, the US Air Force announced it was launching a robotic mini-shuttle from Elon Musk’s SpaceX Falcon 9 rocket for the first time.
The Orbital Test Vehicle-5 mission lifted off from Launch Complex 39A at Nasa’s Kennedy Space Centre in Florida on September 7.
Four previous X-37B missions have been launched by United Launch Alliance Atlas 5 rockets.
Read more: http://www.dailymail.co.uk