We won't be able to do it in perfect Crosby, Stills & Nash harmony, but we should take a moment today to sing 'Happy Birthday' to rock legend Graham Nash, who's turning 70 today (Feb. 2).

Nash has been active in the music business for over 50 years, first as a member of the Hollies and later alongside David Crosby and Stephen Stills (and sometimes Neil Young). A member of the Rock and Roll Hall of Fame twice over, Nash has been inducted as part of both groups. He's also maintained a solo career, recording a handful of albums under his own name; the most recent of which, 'Songs for Survivors,' was released in 2002.

In addition to his music, Nash has stayed busy with a variety of philanthropic activities, including co-founding Musicians United for Safe Energy with Jackson Browne, Bonnie Raitt, and John Hall of Orleans; he's also an avid photography collector, and highly regarded photographer in his own right.

After he blows out all those candles, Nash has some work to do -- he's planning a world tour with Crosby and Stills this year, kicking off in New Zealand toward the end of March.