It was the third SpaceX commercial resupply cargo mission to be lost in the last few months. The rocket was heading to restock the International Space Station but suffered an over pressure event in the upper stage liquid oxygen tank, according to a tweet posted by Musk soon after the explosion.
The Falcon 9 rocket was carrying over four thousand pounds of food as well as new space station hardware. The unmanned rocket also contained roughly 30 different science experiments that SpaceX had picked from their nation-wide program that allows high-school students to conduct experiments in space.
In a press release following the explosion, NASA administrator Charles Bolden said that "the astronauts are safe aboard the station and have sufficient supplies for the next several months" and that NASA will "work closely with SpaceX to understand what happened, fix the problem and return to flight."
But despite NASA's lack of concern, the latest explosion has raised more questions about NASA's plan to outsource resupply missions following the retirement of their space shuttle back in 2011. But the most recent explosion of a SpaceX commercial resupply rocket, along with the two recent crashes before the CRS-7, will not deter neither SpaceX's nor NASA's goal of a human spaceflight program.
With three crashes in the past eight months, SpaceX will continue on track to launch its Dragon rocket flight, their first human-manned rocket flight by 2017. SpaceX's goal is to eventually create affordable commercial spaceflight by making reusable rockets that can be launched and relaunched within the same day in a similar way that an airplane can be used time and time again.