What will replace the space shuttles?

Answer 1

The Constellation program will take over from the space shuttle. See the link below.
The Space Shuttle will be replaced by the Ares rocket system. The Ares heavy-lift rocket has a bigger payload than the Shuttle,the Shuttle can lift about 22 tons into low earth orbit, the Ares can lift 188 tons in low earth orbit. The Ares payload bay is three times larger than the Shuttle's. Old-style rockets and splashdown recoveries might not be as cool as the Shuttle, but they're cheaper and can actually do more.
As of this writing (December 2010) the three remaining Space Shuttles are scheduled to be retired shortly. For the past few years, the US NASA (National Aeronautical and Space Administration) has been planning a new manned-spaceflight system called Orion/Ares. Orion is the manned segment (like Apollo) and Ares is the launch vehicle (like Saturn).
Very recently this fall, NASA has indicated that it may scrap plans for Orion/Ares.
This would leave the US space program without its own manned space flight program.


There are no more servicing missions to Hubble scheduled, so the need for manned flight is somewhat arbitrary at this point -- as there are only fleeting thoughts of returning to the Moon, or going to Mars with manned flight.


Future US manned flight to, say the International Space Station, would be accomplished via Russian launch and manned flight systems.

Answer 2

NASA plans to replace the Space Shuttle Program with the Orion Program based on an Ares I rocket.