American TV star Bill Nye has sparked fears for his health after collapsing on stage during a speech.
The Bill Nye The Science Guy host was giving a presentation at the University of Southern California on Tuesday evening (16Nov10) about science education when he reportedly fainted halfway through a sentence.
Nye, 54, passed out for several seconds before regaining consciousness and continuing the talk, reports the Los Angeles Times.
The star then told the crowd he suffered a similar blackout earlier in the day, before he was escorted off stage.
Paramedics are said to have responded to Nye's collapse but it is unclear whether he was taken to hospital following the incident.