It was a Falcon rocket from Space X with two astronauts on board to be shot from the Kennedy Space Center in Florida. The spacecraft would become the first in nine years when Americans flew to space in a rocket built in the United States.
But when the astronauts were already in place in the rocket and the countdown began to suffer towards its end, so came the message: there will be no start, the weather is too bad.
Tonight you make the attempt and the start is scheduled for 21:22 Swedish time.
However, the weather is still a major factor of uncertainty and NASA estimates that the risk that even the start of the evening is postponed is 50 percent.
In July 2011, NASA's space shuttles flew for the last time. Since then, American astronauts have flown into space in a Russian Soyuz capsule, a service the United States paid for. But now the idea is that the US will return to its own flights, which the two private companies SpaceX and Boeing will be responsible for.
The NASA astronauts who will make the historic spacecraft are named Robert Behnken and Douglas Hurley and the launch will be from the same launch pad on Cape Canaveral that Neil Armstrong, Buzz Aldrin and Michael Collins lifted from the moon in 1969.
SVT News broadcasts directly from the trial starting at 21:10.