Roof collapses at Smithsonian warehouse in Md.

Historic aircraft and spacecraft were exposed to freezing temperatures Wednesday after heavy snow collapsed part of a roof and wall at a Smithsonian Institution storage facility.

No artifacts were thought to be damaged because they are all kept in boxes or protective crates, though some pieces usually are kept at stable temperature and moisture levels, officials said.

Full story:  Roof collapses at Smithsonian warehouse in Md. – Washington Times