Mark S. Weitz, who supplied this photo, is third from the right at a 2008 gig in Malibu, California. Pictured are five original members and two new members.

"Just Dance" was Lady Gaga's first hit, and it also brought the techno-synth sound that had been popular in Europe for the previous decade to the United States.

Richard Harris, who played Professor Dumbledore in the first two Harry Potter movies, had a hit in 1968 with "MacArthur Park."

Katy Perry co-wrote Iggy Azalea's hit single "Black Widow." Perry was originally going to sing on the track, but she couldn't fit it into her schedule, so Rita Ora provided the sung vocals instead.

"Pink Cadillac" was a B-side for Bruce Springsteen in 1984, but after Aretha Franklin sang about pink Cadillacs on "Freeway Of Love" the following year, Natalie Cole covered the song and had a hit with it in 1988.

The line "satellite of love" in the Def Leppard song "Rocket" came from the title of a 1972 Lou Reed song.

Hanson's megahit "MMMbop," released when they were teenagers, is surprisingly profound. Zac Hanson told Songfacts it "represents a frame of time or the futility of life."
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