Coming off their road win over the Dolphins, the Steelers flew to the Louisiana Superdome for a Week 8 interconference duel with the New Orleans Saints on Sunday night.  After a scoreless first quarter, Pittsburgh struck first in the second quarter with a 19-yard field goal from kicker Jeff Reed.  The Saints answered with a 31-yard field goal from kicker Garrett Hartley. New Orleans took the lead as Hartley got a 23-yard field goal.  In the fourth quarter, the Saints increased their lead as quarterback Drew Brees completed a 16-yard touchdown pass to wide receiver Marques Colston.  The Steelers responded with a 38-yard touchdown run from running back Rashard Mendenhall, but New Orleans struck back with Brees completing an 8-yard touchdown pass to wide receiver Lance Moore.. How long was the longest touchdown?