Sam: I'm Sam.
Rob: And I'm Rob.
Sam: Once in a while along comes a scientist
who captures the public imagination and communicates their passion
for science in an exciting and understandable way.
Rob: In this programme,
we'll be meeting one of America's best-known popular scientists.
Astronomer Neil deGrasse Tyson.
He's a man with a gift for communicating and inspiring people
with his television shows and books on cosmology -
the study of the origin and nature of the universe.
Sam: In his day job he runs the Hayden Planetarium
in New York's American Museum of Natural History,
but Neil's real mission is to encourage scientific thinking among the American public.
Rob: We'll be hearing from the famous astronomer,
and learning some new vocabulary, soon.
But first I have a question for you, Sam.
Science is ever-changing with new discoveries updating our understanding all the time.
For centuries, the Earth was thought to be the centre of the Universe -
but who was the first astronomer to have the correct idea that,