Five things about the success, strategy and the implications of the successful return of SpaceX’s Falcon 9 to earth
1. WHY DO THIS: Typically, rockets exhaust their fuel by the time they reach the boundary between earth and space and plummet to the sea. For space missions such as ‘Blue Origin’ (funded by Jeff Bezos) and Falcon, their efforts are to get the main rockets back on earth. Doing that can save nearly 55 per cent-75 per cent of launch costs.
2. WHAT'S THE USUAL PROCEDURE: Previous attempts involve SpaceX trying to land its Falcon 9 boosters on a floating platform in the Atlantic Ocean. While the boosters made it close, they faltered towards the end by either running out of hydraulic fluid, crashing or having the booster topple over.
3. WHAT DID ‘FALCON’ DO THIS TIME: First, rather than land on bases further away from the launch pad, they opted to bring the rockets to Cape Canaveral which is closer. To achieve that, the rocket boosters have to rise, release the space probe and flip back for a return. The engineers at SpaceX therefore managed to dramatically cool the fuel such that more could be accommodated within the tank. The second stage of the rocket, in contrast, was tanked with more fuel that would allow it to separate earlier from the rocket stage and power the space craft. A rocket that isn't too far away makes it easier to control and brought back to a desired spot.
4. SO HAVE ALL PROBLEMS WITH RE-USABILITY BEEN RESOLVED: Not really. For one, it will take a few years for the Falcon 9's rocket stages to be refurbished and ready for another launch. Only then would it be proof that a rocket has actually been re-used. Second, the satellite payload aboard the ‘Falcon’ was relatively light, made up of 11 functional and 1 dummy satellite/s of about 175kg each -- with mounting and ejection hardware and so on, probably less than 4 tons of payload, compared to the 13-ton payload Falcon 9 is normally capable of launching to low earth orbit. It remains to be seen if similar design principles can be used to launch heavier payloads.
5. SHOULD ISRO BE WORRIED: Not yet. For one, the Indian Space Research Organisation (ISRO)'s launching costs are still extremely low given that the workhorse, the Polar Satellite Launch Vehicle, is now a well-proved vehicle for mid-sized payloads. By the time Space X gets to actually re-using old rockets, ISRO --- if as it has claimed--- would have conducted vital tests on its own reusable vehicle mission. However, the commercial space race is rapidly heating up and technological advancement --- once it crosses certain milestones--- tends to accelerate, so ISRO has time but cannot afford to be complacent.
