12 month 7 day , Sunday local time , Space Exploration Technologies Inc SpaceX Using recycled Falcons 9 Rocket booster will be the first upgraded cargo dragon spacecraft 2 Number (Cargo
Dragon 2) Safe launch into orbit , For the first time in the company's history, the company has set up a new mode of keeping two dragon spaceships in orbit at the same time .

   chart :SpaceX Using recycled Falcons 9 Rocket booster to launch an upgraded cargo dragon spacecraft into space

  SpaceX since 2012 It has been replenishing the international space station since 2000 , Before 20 In the next task , The company used the original version of the cargo dragon . however ,SpaceX
Never stop developing new spaceships . this year 5 month , The manned Longfei ship launched the first crew into space . With the new version of the Dragon spaceship put into use ,SpaceX
Decided to stop using the old cargo ship , It's using an upgraded version of the ship to transport astronauts and cargo .

   Cargo dragon spacecraft 2 It has been upgraded several times on the basis of its predecessor .SpaceX express , It can carry more 50%
Scientific instrument payload , And it can automatically dock with the space station . The original version could only slowly approach the ISS , It is then captured by the astronauts above using a robotic arm , And transfer to the open docking port . Cargo dragon spacecraft
2 It doesn't need any human help to dock .

   The mission will bring the necessary supplies to the space station and astronauts , Several experimental equipment will also be brought to the international space station . Among them are the European Space Agency's
Bioasteroid, It will test how biological processes are affected by microgravity . The so-called biological action refers to , The process of extracting elements from rocks by microorganisms .

   in addition , The mission will also novel coronavirus pneumonia research on the spacecraft. , Try to improve the antiviral drug radcivir (Remdesivir) The efficiency of . At the same time, it also carries NanoRock
Company's commercial airlock , It's a large metal cup attached to the outside of the international space station , Used to send payloads and other materials into space from the pressurized environment of the international space station .

   The first commercial manned launch mission was completed by the manned dragon spacecraft (Crew-1, That is, to send astronauts to the international space station for the second time ) after ,Crew-1 And the cargo dragon 2 No CRS-21
The resupply mission also represents SpaceX The fastest Dragon Ship in history “ Back to back ” launch .SpaceX In a short time 61 Days of success against the Falcon 9 Booster No.1 b1058
Carry out renovation , Use it to launch CRS-21 task . According to the average turnaround time 60 Day count , A falcon 9 The rocket booster can support the annual test 6 Secondary emission .

   meanwhile , Each upgraded cargo Dragon Ship 2 Are designed to support at least 5 Suborbital mission , And the manned dragon spacecraft is already planned for 4 The first repeated manned mission was carried out after six months .

   according to SpaceX And NASA Schedule developed , The company 2021 There will be at least as many launch missions as this year . In order to achieve this ambitious goal ,SpaceX and
NASA It will have to rely more than ever on the reusability of rocket boosters and spacecraft . Fortunately ,CRS-21 It has expanded NASA Approved Falcon 9
Reusable range of rocket booster .

   Cargo dragon spacecraft 2 Is on its way to the international space station , And it's scheduled for Eastern time 12 month 7 Independent docking will be carried out in the afternoon of June . At that time ,SpaceX
Two Longfei ships will meet on the space station for the first time .11 month 15 day ,SpaceX The manned dragon spacecraft successfully sent four astronauts to the international space station , And 1 Tian Tian successfully connected with the space station .SpaceX
Sara, dragon spaceship mission manager · Walker (Sarah Walker) express :“ This will be the first time two dragon spaceships will be on board at the same time . In the near future , At least to 2021
end of the year , We're going to have a period when the Dragon spacecraft will stay in space .”( Small )