The space shuttle Atlantis 11-day journey for seven astronauts ended on Friday at 9:44 a.m. EST at NASA's Kennedy Space Center in Florida.
What the shuttle crew completed was a delivery of about 30,000 pounds of replacement parts for systems that provide power to the station, keep it from overheating, and maintain a proper orientation in space.
Some government technology that NASA manages in space is the Global Positioning System (GPS) navigator. "For GPS to work, the orbital position, or ephemeris, of the satellites has to be known very precisely," said Dr. Chopo Ma of NASA's Goddard Space Flight Center in Greenbelt, Md. "In order to know where the satellites are, you have to know the orientation of the Earth very precisely."
Global Positioning System provides directions for millions daily via signals from GPS satellites to a receiver in your GPS navigator. The GPS navigator calculates your positions based on the location of the satellites and your distance from them. Per the NASA website , just as you can use landmarks to find your place in a strange city, astronomers use landmarks in space to position the Earth. Stars seem the obvious candidate, and they were used throughout history to navigate on Earth. "However, for the extremely precise measurements needed for things like GPS, stars won't work, because they are moving too," says Ma.
What's next for NASA? Another shuttle will launch called the Endeavour targeted for February. The Endeavour will deliver a pressurized module, known as Tranquility, which will provide room for many of the space station's life support systems.