"But be patient with us. Let's make sure that the vehicle is ready to go and that our team is really certain before we hit the button."

NASA's next crew of astronauts are set to launch on a SpaceX rocket to the International Space Station. Liftoff is set for July 31 from KSC, Florida.

NASA's Crew 11 arrives at Kennedy Space Center, Fla., on Saturday. Asteroid 2024 YR4, which once appeared to be on a collision course with Earth, may hit the moon, which could create some problems for our planet.