Step 1: Pin down what is being asked.
We need the private aerospace company that tied up with NASA to fly the first private astronaut mission to the ISS.
Step 2: Recall NASA's Commercial Crew setup.
Since 2020, NASA has relied on SpaceX's Dragon capsule to ferry astronauts to the ISS, and this same Dragon vehicle has also carried private crews organised by companies like Axiom Space under NASA's agreements.
Step 3: Rule out the distractors.
Blue Origin mainly runs suborbital tourism and lunar lander work, Boeing's Starliner has had a separate and delayed crew contract, and Vast Space is still building its own future station - none of them flew the first private ISS mission.
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