Rare SpaceX rocket failure shows exactly why NASA wants 2 commercial options to fly astronauts to ISS

Six years ago, a rare Russian abort during an astronaut launch caused delays in human spacecraft schedules. This week, NASA may face the same after a rare failure during a SpaceX launch. Back in 2018, a Russian Soyuz spacecraft was bound for the International Space Station (ISS) when a sensor issue aboard the rocket (also called Soyuz) forced the crew to escape in an emergency abort during liftoff. The two astronauts on board were safe, but for several weeks, it was unclear if the usual six-month rotation of ISS crews would be disrupted. More

(Source: Space.com - Jul 18)