1. Mariah Carey shared this awesome photo of her and Britney Spears hanging out together in 1999:
2. Nicole Richie posted this sweet photo from the '80s of herself in Rashida Jones' lap:
3. Robert Downey Jr. shared this promotional photo of him and Jude Law from their 2009 film, Sherlock Holmes:
4. Julia Roberts posted this behind-the-scenes photo from her 1999 film, Notting Hill.
5. RuPaul shared this photo of himself from 1980:
Me at 19. https://t.co/6DLlAExEDq
6. Dolly Parton posted this photo of herself at the opening of her amusement park, Dollywood, in 1986:
7. Janet Jackson celebrated the 25th anniversary of her film Poetic Justice by sharing this promotional photo of herself and her co-star, the late Tupac Shakur:
8. Hugh Jackman posted his 1998 headshot:
9. Diana Ross celebrated the 35th anniversary of her legendary Central Park concert by sharing this video clip from it:
10. Iman celebrated her 63rd birthday by posting some of the magazine covers she has appeared on throughout her legendary career:
11. Susan Sarandon posted this photo from her first wedding to actor Chris Sarandon in 1967:
12. Natalie Portman remembered when she went to the Venice Film Festival for the first time in 2010, to promote her film Black Swan:
13. Eminem posted this photo of himself hanging out with Birdman and Lil Wayne at the 2000 BET Awards:
Remember that time I was in Ca$h Money? #tbt
14. Katherine McPhee shared this photo of herself and Hilary Duff hanging out together at an event in 2008:
#tbt me and the actual inventor of rain