"It's an important day in American history (or, at least, in American cinematic history):

"It's the date to which Marty McFly traveled into the "future" in Back to the Future Part II.

"We've come a long way in the 30 years that have passed since the original Back to the Future came out. Now, we're going to talk about where we're going in the next 30. 

"All day long, we're hosting a series of conversations with scientists and innovators across the government and the country. You'll be able to ask them questions, watch videos explaining their cutting-edge developments, and share your answer to the question above: What does 2045 look like?"