Dirty

This small dark rectangle on the ceiling of the main Grand Central concourse is the sole remaining evidence of the color that used to cover the entire ceiling. Thought to be the collected diesel smoke from decades of trains, or smog, or steel rail filings, it turned out on forensic examination that the dark color was actually accumulated tar and nicotine from decades of cigarette smoke.

As part of a major renovation of the terminal done between 1996 and 1998, the ceiling was fully cleaned, uncovering the stunning map of the stars beneath the soot.

Click here to read the related behind-the-scenes story on the secrets of Grand Central Terminal. And click here to check out the entire Road Trip 2010 package.