in 2008, spacex won a commercial resupply services (crs) contract in nasa's commercial orbital transportation services (cots) program. they would take cargo to the international space station (iss) using the falcon 9 and dragon capsule. the first mission under this contract launched on 8 october 2012. falcon 9 can take nasa astronauts to the iss. it is also certified for the national security space launch program and nasa launch services program as "category 3". this means it can be used with the most expensive, important and complex nasa missions. falcon 9 is said to be the world's most advanced space launch vehicle by many sources. as of january 2021, falcon 9 has the most launches among all u.s. rockets that are currently being used. it is the only u.s. rocket fully certified for transporting humans to the international space station. it is also the only commercial rocket to take humans to orbit. on 24 january 2021, falcon 9 set a new record for the most satellites launched by a single rocket. it carried 143 satellites into orbit.