The four astronauts - Chris Ferguson, shuttle's commander, Sandy Magnus, Douglas Hurley, shuttle's pilot, and Rex Walheim - aboard Space Shuttle Atlantis started their ninth gravity-free day with a special message from songstress Beyoncé Knowles, who gave a surprise inspirational message to the astronauts aboard space shuttle Atlantis Sunday morning.

Good morning, Atlantis. This is Beyoncé , she told the crew aboard the NASA space shuttle. Sandy, Chris, Doug and Rex, you inspire all of us to dare to live our dreams, to know that we're strong enough and smart enough to achieve them.

She added, This song is especially for my girl Sandy, Beyoncé told mission specialist Sandy Magnus as Run the World (Girls) played over the speaker. And all the women who've taken us to space with them and the girls who are our future explorers.

MSNBC reports, astronaut Sandy Magnus responded to the Johnson Space Center in Houston, TX, also the singer's hometown, saying Good morning, Houston! A big thanks to Beyoncé for taking some time out of her schedule to record us a greeting. We're ready for another day here in Atlantis! Hopefully we as a team at NASA can keep our inspirational work up for the young people of America.

Shuttle Atlantis is bound for the International Space Station to deliver supplies before touching back down in Florida in less than a week.

Atlantis' engineer, Frank Svrcek told ABC News, It takes something like this to really emphasize the complexity, how did we ever do that, to get there - how did we ever fly the shuttle given its complexity. He added, We have to simulate the world, the environment. We have to simulate the main engines, it has to all work together, time and time again.