Nova Sciencenow

NOVA scienceNOW host and astrophysicist Neil deGrasse Tyson offers a birthday greeting to America's space agency. NOVA is produced by WGBH in Boston. Major funding for NOVA scienceNOW is provided by Pfizer, the National Science Foundation, and the Howard Hughes Medical Institute. Additional funding is provided by the Alfred P. Sloan Foundation. This material is based upon work supported by the National Science Foundation under Grant No. 0229297. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation. For more fun science stories, visit our Web site at pbs.org/nova/sciencenow