| The crew compartment itself
was crowded but efficiently designed.
Columbia is certainly among the
most historic artifacts in the National Collection. It has been
selected as a Milestone of Flight and has been provided the most
sophisticated protective case of any of our objects. To keep dust
from accumulating on the spacecraft surfaces, a small tube has
been introduced into the enclosure that continually feeds in dehumidified,
filtered air that maintains a slight positive pressure within
the enclosure and prevents the entry of ambient dust and pollution.