As Atlantis prepares for the final space shuttle launch ever, curious kids are wondering how future astronauts will travel to outer space. Without a space shuttle, how will astronauts fly?

Unlike the Apollo missions that sent men deep into outer space to the moon, the space shuttle was made to take astronauts and cargo into low Earth orbit. “Low Earth orbit” means the space shuttle travels an elliptical path around the Earth about 100 to 1,240 miles above its surface.

Since the first space shuttle flight in 1981, there have been more than 130 space shuttle launches. The space shuttle has been used for many interesting missions.

Space shuttles have taken astronauts into space, launched satellites, completed scientific experiments, fixed other spacecraft and played an essential role in the building and maintenance of the International Space Station.

Over the course of the space shuttle program, there have been six orbiters. The orbiter is the big, white space plane most people think of when they think of the space shuttle.

The last three orbiters to fly missions were Discovery, Endeavour and Atlantis. Challenger and Columbia were both lost due to tragic accidents. Enterprise was used as a test vehicle and never flew into space.

When the space shuttle was first launched, it represented a huge leap forward in technology because it became the world’s first reusable spacecraft. It was also unique in that it launched like a rocket, orbited the Earth like a spacecraft and landed like an airplane.

With the upcoming launch of Atlantis, the space shuttle program will finally come to an end. Future astronauts may be able to hitch a ride to the International Space Station with one of the United States’ international partners, such as Russia. Private companies may also soon be able to fly astronauts to the International Space Station in newly developed vehicles.

The next step for the American space program appears to be a return to deep-space missions. The National Aeronautics and Space Administration (NASA) recently announced that it will develop a space capsule — called the “Multi-Purpose Crew Vehicle” (MPCV) — able to carry four astronauts into deep space to locations such as the moon, an asteroid or Mars.

NASA hopes to have the new MPCV flying into space by about 2016. Like the old Apollo spacecraft, the MPCV will splash into the Pacific Ocean upon its return to Earth.

That’s about the only thing that’s like the past, though, as NASA claims the MPCV will be much larger and much safer to launch and land than the space shuttle.