Celebrity guests at the ceremony included Samuel L. Jackson and Ron Howard, both of whom shared their congratulations via Twitter.
"Let's give a Galactic shout out to Master George Lucas & his bride Melodie on this, their wedding day," Jackson tweeted.
"George Lucas Melody Hobson wedding was joy to behold Bill Moyers service was beautiful, nothing short of profound. Congrats Mr&Mrs Lucas," Howard wrote.
Hobson, 44, who heads investment management firm Ariel Investments, got engaged to Lucas, 69, in January after six years of dating.
Lucas was previously married to film editor Marcia Lucas, but the couple called it splits in 1986 after 14 years of marriage.
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