It's a big day for space fans today.
Apollo 11's astronauts are returning to the exact spot from where they flew to the moon 50 years ago.
NASA has invited Buzz Aldrin and Michael Collins to Kennedy Space Center's Launch Complex 39A today.
They will mark the precise moment -- 9:32 a.m. on July 16, 1969 -- that their Saturn V rocket departed on an eight-day voyage for humanity's first moon landing.
Mission commander Neil Armstrong, who took the first lunar footsteps, died in 2012.
Also this morning, five-thousand model rockets will launch simultaneously at the U-S Space and Rocket Center in Huntsville, Alabama.