... Credit: 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. ... Publications with keywords: Mars . ... Victoria Crater on Mars . ... Inside Victoria Crater on Mars . A Path Into Victoria Crater on Mars . ...