Neal deGrasse Tyson is the most popular astrophysicists of today. He has taken the mantle once held by Carl Sagan. His ability to simplify and explain our relationship with science and the cosmos has made him a popular guest on many TV network shows.
Dr Tyson will soon be hosting a new sixteen part science documentary beginning in late March or early April on Fox and the History Channel.
Dr Tyson has given a number of interesting lectures ranging from black holes to UFOs to religion verses science. Many of these are available on YOUTUBE and worth the time viewing.
Check it out