Mars Then and Now . ... Credit Copyright: Tom Ruen , Eugene Antoniadi, Lowell Hess, Roy A. Gallant , HST , NASA . Explanation: Does Mars have canals? A hot debate topic of the late 1800s, several prominent astronomers including Percival Lowell not only claimed to see an extensive system of long straight canals on Mars, but used them to indicate that intelligent life exists there. ... NASA Web Site Statements, Warnings, and Disclaimers . NASA Official: Jay Norris. ...