An earth observation satellite sitting atop an Atlas V rocket at Vandenberg Air Force Base has had its launch delayed again, this time because of a nearby wildfire.

The WorldView 4 earth observation satellite was scheduled to launch from Vandenberg Space Launch Complex 3 at 11:30 a.m. Sept. 18, but the launch was scrubbed because of a wildfire on Vandenberg property that began Sept. 17.

Because of the delay, the launch will happen no earlier than Sept. 26 due to availability of tracking, communications and safety services on Vandenberg’s western rocket range.

Originally scheduled for Sept. 16, the launch was initially delayed at the last minute because of a minor leak in one of the ground propellant tanks.

The United Launch Alliance, a joint venture between Lockheed Martin Space Systems and Boeing Defense, Space and Security, plans to launch the rocket from Vandenberg’s Space Launch Complex 3. DigitalGlobe, a Colorado-based imaging and data company, will operate the satellite once it reaches orbit.

Planning for the mission started in 2007 under the name GeoEye-2 and was slated to launch in the spring of 2013. The satellite’s launch was delayed three years because of a merger. In January 2013, competitors DigitalGlobe and GeoEye merged operations of the independent fleets of imaging satellites.

After the merger, the company decided to launch another similar satellite being developed by Digital Globe first.

Final preparations were made to the satellite Sept. 8 as technicians at Vandenberg encapsulated the satellite in a white, 4-meter tall protective nose cone.

• Contact Philip Joens at pjoens@pacbiztimes.com.