The year 2009 marked a transformative era for pop music.

It set the tone for the sound of the 2010s and also solidified or introduced a number of big new stars. Justin Bieber made his explosive teen-pop debut, while Lady Gaga further expanded the smash success of her debut album with a boundary-pushing standalone expanded edition.

The year also ushered in the electro-pop resurgence with releases from Owl City and La Roux, and pushed forward the Disney teen-pop agenda with releases from Selena Gomez, Ashley Tisdale, Demi Lovato and more.

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Meanwhile, veteran pop icons such as Madonna and Mariah Carey saw both commercial and critical success with new albums.

However, 2009 was also the year the world said goodbye to a one-in-a-lifetime artist: Michael Jackson. Despite losing the King of Pop, the music industry soldiered on, and fans celebrated his legacy with the release of a posthumous album.

Time sure flies, and as another new year unfurls, it's hard to believe all these albums and EPs are turning 15 in 2024.

Pop Albums Turning 15 in 2024

These 25 albums from 2009 turn 15 years old in 2024.

Gallery Credit: Ryan Reichard