Columbia Accident Investigation Board

During re-entry into the Earth's atmosphere, this damage allowed super-heated gases to enter and erode the inner wing structure which led to the destruction of Columbia.

NASA decided that it did not warrant an extra EVA (extravehicular activity) for visual inspection, feeling that it would be like a car going down a highway and hitting a Styrofoam cooler.

As part of the CAIB recommendations, the Shuttle carried a 50-foot inspection boom attached to the robot arm, which was used within 24 hours of launch to check the orbiter for damage.

As all but one of the post-Columbia missions were concentrated on the International Space Station, primarily to provide a "safe haven" in the event an orbiter was damaged beyond the normal repair methods, NASA implemented a STS-3xx contingency mission program that could launch a rescue orbiter on short notice, similar to the Skylab Rescue that was planned during the Skylab program.

[8] President Obama signed the NASA Authorization Act 2010 on October 11 which officially brought the Constellation program to an end, replacing it with the Space Launch System (SLS) and Multi-Purpose Crew Vehicle (MPCV) programs to develop the launch vehicle and spacecraft to enable human exploration missions beyond low-Earth orbit.