Update May 4th, 2:55AM ET: After delays earlier in the week, SpaceX successfully launched the CRS17 mission to the ISS at 2:48 AM ET on Saturday, May 4. The Falcon 9 booster also successfully touched down on SpaceX’s drone ship. Our updated post continues below.
Early Saturday morning, SpaceX launched a Dragon cargo capsule to orbit, loaded with supplies and science experiments for the International Space Station. It’s an otherwise routine launch for the company — the 17th one that SpaceX has launched for NASA since 2012. However, this mission comes two weeks after the passenger version of SpaceX’s Dragon capsule exploded during an engine test.
The exact cause of that accident has yet to be identified, but the cargo version of SpaceX’s Dragon capsule is a very different vehicle than the passenger version, known as Crew Dragon. Last week’s accident occurred during scheduled tests of the Crew Dragon’s eight SuperDraco engines, tiny thrusters embedded within the outer shell of the capsule. If a future flight of the Crew Dragon goes awry, the SuperDraco engines can ignite and quickly carry the capsule away from a dangerous rocket. The Crew Dragon exploded just before SpaceX ignited all eight of these SuperDracos on April 20th at the company’s landing pad in Cape Canaveral, Florida.
Since the cargo Dragon is not equipped with SuperDracos, both SpaceX and its partner NASA were confident enough to move ahead with this week’s flight. However, Saturday’s mission did change slightly due to the accident. Originally, SpaceX planned to land its Falcon 9 rocket on the company’s landing pad following takeoff. But in the wake of the failure, SpaceX has been collecting data and hardware from the explosion at the pad, so it’s not the best spot to land a rocket at the moment. SpaceX will try to land the rocket on one of the company’s floating drone ships in the Atlantic Ocean instead.
The cargo Dragon going up on this week’s flight is packed with more than 250 experiments that the astronauts on board the ISS will utilize in the months ahead. The Dragon is also carrying a few special items in its unpressurized trunk — a cylindrical structure that rides attached to the capsule during flight, providing support and power. Within the trunk is an experiment from NASA called OCO-3, which will help the space agency measure the Earth’s carbon dioxide levels. Once the cargo Dragon reaches the space station, the robotic arm will place OCO-3 on the outside of the space station, where the instrument will help scientists learn how carbon dioxide fluctuates all over the world.
Originally, SpaceX was supposed to launch the cargo capsule earlier in the week, but NASA had to delay the launch due to a power outage on the station that has since been fixed. A backup launch of 3:11AM ET on Friday, May 3rd was also postponed due to an electrical issue with the drone ship meant to collect the booster. Those issues were fixed before Saturday’s launch at 2:48 AM ET. The Dragon capsule should meet up with the space station on Monday, May 6th, when astronauts will grab the vehicle with the space station’s robotic arm and move it onto an available port.