Billionaire Elon Musk’s scheme to dramatically slash prices for launching satellites into space came much closer on April 8th when a SpaceX Falcon 9 rocket successfully landed onto a floating barge after delivering a cargo up to the International Space Station.
The mission is key to Musk’s plans. This is the first time SpaceX has managed to land successfully onto a barge, and 4 previous attempts have failed. SpaceX has managed a successful landing on Earth (last December at a special site in Cape Canaveral, Florida).
If Musk can now perfect the technology and make it even reasonably successful then he will be well on his way to reusing these lower stages of the Falcon-9 rocket , and thus pass on to customers some of the significant cost-savings achieved.
Some observers have suggested that satellite launch costs for SpaceX – currently around $60 million per launch – could tumble by more than one third.
SpaceX’s barge landings at sea are a necessary evil. The barge is placed several hundred miles down range from the launch site. When the upper stage is released and continues with its payload into space the lower stage, still with some precious fuel on board, can be guided towards the ocean and as Friday’s ‘landing’ proved, can be placed with pin-point accuracy onto the barge.
A ground-based landing, while eliminating the risks of ocean swells and rough water, is harder to achieve in that the rocket’s engine has to be restarted in a series of precise burns and completely turn around in order to bring the lower stage back to – more or less – its start point.
This particular barge landing was just about perfect, with the rocket landing just 1 metre away from the ‘X marks the spot’ target. And the ocean was far from calm. From lift-off to its landing the journey took just 8.5 minutes, and three engine ‘burns’ to complete.
“The thing that was a little different about this mission on the rocket side was that the rocket landed instead of putting a hole in the ship or tipping over,” said Elon Musk, SpaceX’s CEO, in a post-launch press conference April 8th.
April 9th saw specialist teams board the barge in order to weld the rocket’s landing struts to the barge’s deck, and start the journey back to land, expected on April 10th. The stage would then undertake some static ground-based engine tests and a thorough examination to check on its condition, and if all is well be re-used on an upcoming mission, perhaps as early as June.
Musk said there were possibilities that the ‘one previous use’ stage would be used for a paying client. That customer could even be Luxembourg-based satellite operator SES. Its Annual Report to investors, issued on April 7th, talked about it being the first customer to re-use a SpaceX rocket.