After a last minute launch abort Monday, SpaceX was able to send its sixth resupply mission to the International Space Station (ISS) on Tuesday afternoon. This is part of the company’s 12-mission NASA contract to ferry food and equipment to the ISS, but it was also an opportunity for SpaceX to test its reusable Falcon 9 rocket. While the launch went as expected, the rocket failed to survive its landing for a second time. Here’s what happened.
SpaceX’s current launch vehicle is a two-stage solution. The Falcon 9 first stage is powered by nine Merlin engines producing nearly 6000 kN of thrust. After reaching an appropriate altitude, the first stage drops off, and the second stage with its single Merlin vacuum engine continues into orbit with the unmanned Dragon capsule. This part went off without a hitch on Tuesday and Dragon is on its way to the ISS, which is good. Astronauts aboard the ISS need supplies, and this is the part of the mission SpaceX is being paid for.
The second part of the launch was SpaceX’s test of its reusable rocket technology. The idea is instead of the first stage falling off and crashing into the ocean, as is the usual method, the Falcon 9 first stage could one day make a gentle vertical landing and be refueled for another launch. Shortly after the launch, SpaceX CEO Elon Musk announced that the Falcon 9 had landed on the drone ship floating in the Atlantic, but touchdown was too hard for it to survive.