Discuss as:

SpaceX's 3 minutes of heavenly hell

A SpaceX' video recaps the test firing of the company's Merlin 1D engine.

SpaceX is basking in the glow of last month's successful cargo mission to the International Space Station, but it's also celebrating the glow of its next-generation Merlin 1D rocket engine, which has now gone through a full mission duration firing of 185 seconds.

The California-based company said today that the engine firing took place at its rocket development facility in McGregor, Texas, on a test stand near the building where the recently returned Dragon cargo capsule is being kept. The test reached 147,000 pounds of thrust, satisfying the duration and power requirements for a Falcon 9 launch. SpaceX also tested the Merlin 1D's capability for multiple restarts.

"This is another important milestone in our efforts to push the boundaries of space technology," SpaceX CEO and chief designer Elon Musk said in today's announcement. "With the Merlin 1D powering the Falcon 9 and Falcon Heavy rockets, SpaceX will be capable of carrying a full range of payloads to orbit."

The Merlin 1D represents an enhancement of the Merlin 1C engines that are being used on the Falcon 9's first flights. SpaceX said the 1D should open the way for "improved manufacturability by using higher-efficiency processes, increased robotic construction and reduced parts count." The new engine's structural and thermal safety margins play a key part in SpaceX's plans to start launching astronauts into space as early as 2015.

SpaceX says the Merlin 1D's should see their first flight on Falcon 9 Flight 6, due for liftoff next year.

Also today, Aerojet's AJ26 rocket engine was test-fired at NASA's Stennis Space Center in Mississippi, according to a Twitter update from the space agency's rocket test complex. The AJ26 is to be used on Orbital Sciences Corp.'s Antares rocket. Like SpaceX, Orbital has been receiving hundreds of millions of dollars from NASA to support the development of a launch system capable of resupplying the space station. Orbital says the first Antares test flight will be launched later this summer.


A picture from NASA's Stennis Space Center shows the test firing of Aerojet's AJ26 rocket engine.

Alan Boyle is msnbc.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.