"The 18-time Grammy victor (44 nominations) who died August 16 at the age of 76 was known for timeless hits like "Respect" and "(You Make Me Feel Like) A Natural Woman".
Her powerful voice, seared with emotion, would become the daunting standard for other singers to match, but fans described a legacy beyond her most famous recordings.
Tuesday's and Wednesday's public viewing was scheduled to last from 9 a.m.to 9 p.m. each day.
Outside the museum, she said: "I know people are sad, but it's just celebrating - people dancing and singing her music". She was in repose, dressed in red from head to high-heeled shoes, legs crossed at the ankles.
"I think it's incredibly significant - she is being honored nearly like a queen at one of the most important black museums in the United States", said Ms Seniors.
Hasn't Serena Williams earned the right to wear whatever she wants?
She once revealed: "I have been wearing trousers in general a lot when I play, so I can keep the blood circulation going. His voiceover continues as the footage cuts back-and-forth to an older version of the tennis icon competing at the U.S.
The Queen of Soul, Seniors said, was "a singer of the universe".
A family is photographed beneath a mural in tribute to the late singer Aretha Franklin outside the New Bethel Baptist Church in Detroit, Michigan.
Former US president Bill Clinton, who had Franklin sing at his 1993 inauguration celebrations, will be among the speakers.
The funeral for Franklin is set for Friday, at Greater Grace Temple in Detroit, with stars including Stevie Wonder and Jennifer Hudson set to perform.
While Friday's funeral is closed to the public, the streets outside are to be lined with dozens of pink Cadillacs, the Detroit-built luxury cars.
The motorcade of the vehicles will be in honor of Franklin and her hit song, "Freeway of Love".