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Musk’s Space X finally launches first US national security space mission

A Space X Falcon 9 rocket successfully launched in the US this afternoon, after four successive failed attempts to carry out the company's first national security space mission.

The rocket, which was carrying a satellite worth roughly $500m (£393.7m) built by Lockheed Martin, blasted off from Florida just before 2pm GMT.

The satellite's launch was initially planned for Tuesday, but failed due to technical issues. Other attempts on Wednesday, Thursday and yesterday were also aborted due to similar problems and bad weather.

There were also some concerns that a potential US government shutdown might halt proceedings, due to a lock on funding for the mission. The US Air Force monitors the location of the launch known as the 45th Space Wing, helping to set up road blocks and clear relevant air space.

The launch is a milestone for Space X chief and Tesla billionaire Elon Musk, who has spent years trying to break into the defence space sector dominated by Boeing and Lockheed.

Space X was awarded part of a multi-billion-dollar contract by the US military, alongside Boeing and Lockheed's joint venture United Launch Alliance, for 36 rocket launches. 

The GPS III satellite, which has a lifespan of 15 years, is the first of 32 to be built by Lockheed in contracts worth a combined $12.6bn from the US Air Force.

Space X will now finish 2018 with 21 launches, surpassing its own record of 18 missions last year.

Musk later tweeted to applaud the launch:

The next satellite is due to launch in mid-2019.