Lucas, 69, and Hobson, 44, met in 2006 and announced their engagement last January.
UsMagazine.com said they were married this past Saturday, but the celebrity news website did not report where the ceremony took place.
"Let's give a galactic shout out to Master George Lucas and his bride Mellody on this, their wedding day," Jackson tweeted.
"George Lucas and Mellody Hobson's wedding was joy to behold. Bill Moyer's service was beautiful, nothing short of profound. Congrats Mr. and Mrs. Lucas," Howard said via Twitter.
Lucas is the creator of the blockbuster "Star Wars" and "Indiana Jones" film franchises.