Orbital is investigating what went wrong Tuesday night, and all of its future NASA launches are on hold until it can determine the cause of the explosion. Was there a problem with the AJ-26 engine it uses in its Antares rocket, an older Russian engine refurbished by Aerojet-Rocketdyne, part of GenCorp? One AJ-26 exploded during a test last May. Could it be the newer, more powerful motor Orbital was using for the first time in its second stage? (Unlike SpaceX, the rocket Orbital Sciences uses isn't completely made in house.)
Two years ago in an interview with Wired Magazine, Musk was critical of Orbital's AJ-26 engine. "Their rocket honestly sounds like the punch line to a joke. It uses Russian rocket engines that were made in the '60s. I don't mean their design is from the '60s—I mean they start with engines that were literally made in the '60s."
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Tuesday night, Musk was more subdued, tweeting:
While no SpaceX mission has failed yet, Musk's company did suffer an explosion earlier this year while testing a next generation rocket it's working on.
Finally, unlike SpaceX, Orbital Sciences was not chosen by NASA to develop a system to take astronauts to the space station. Orbital can only ferry cargo. For manned missions, Musk is facing off against Boeing to win the eventual contract. Boeing is a company with a far longer history in space and a much deeper relationship with NASA. Boeing uses Atlas rockets, which also have Russian-made engines. Newer ones. In fact, an Atlas V carrying a Boeing GPS satellite into orbit remain scheduled to launch Wednesday afternoon from Florida despite the explosion in Virginia.
"Launching rockets is an incredibly difficult undertaking," NASA said in a statement after Tuesday's night's explosion. "We learn from each success and each setback." And suddenly a lot of people are learning for the first time about a rocket company that has long been flying under the radar.