In the first episode of the new series, Tyson shows Carl Sagan's 1975 date planner, pointing out the day he met up with Carl. There is nothing else on the page for the nearby days. Sagan's schedule book seems awfully not-worn and awfully empty for such a busy scientist...
(Of course it's probable that it was an identical prop schedule with an artist reproducing just that day, especially if the real one was too jam-packed with distracting notes which viewers would be picking apart in hopes of a Freeze-Frame Bonus instead of listening to what Tyson was saying.)
Stepping into Rule of Funny here, it would be distracting if the next day had something like "Crush the ideals those religious nuts hold so dear. Science Rulez!"
Anne Druyan claims in the DVD commentary that it's the real one, found in an attic or similar. If it were kept in a cool dry place, it could easily have lasted that long in good condition. As for why it's so empty, it was midwinter, so maybe Carl was taking time off with family that week.
Don't knock it, I'm in full agreement with Neil here, but to be fair to creationists in terms of "light hasn't had enough time to travel across the universe" when Neil talks about the universe couldn't be 6,000 years old it could be the universe was made by The Powers That Be with all the light placed already on its way everywhere.
The issue with that is if you follow that train of logic, you end up in the whole "Next-Thursdayism" philosophy, where you have no reason to believe that the universe wasn't simply created this week with all of our previous memories preprogrammed into us. There are an infinite amount of potentially true scenarios, but it doesn't pay to follow a train of thought until you have sufficient evidence pointing out that it might be the case.
Indeed, a full understanding of thermodynamics suggests that it's more likely the universe was created, as we know it, yesterday rather than six thousand years ago, or even fourteen billion. However there is another counterargument that I've never seen scientists address, and that's the idea that the c constant itself may have changed, with light originally moving at much higher speeds and gradually slowing down to the rate we now know.
Except that this escape hatch won't work, so the creationists still have no excuse. And in any case, there has never been any actual evidence for the hypothesis that the speed of light was ever different to begin with, so it still would not be valid science.
First, even if the universe was created yesterday with everything before that made up... it would still be pretty darn interesting to discover this false history as well as the creation of that false history. Second, c is not how fast light travels. c is simply a numerical value that describes the maximum speed possible in the universe (which also happens to be the speed of light in a vacuum). Light itself can move at many different speeds - any prism can show that. As for whether c itself could change - that's certainly a possibility and there would probably be signs of it - the challenge is not that people are ignoring the possibility (even people you may not have heard about). The challenge is coming up a proper way to test and validate the idea. After all, I can suggest that you may be male and have a 50% (give or take) of being right just by guessing. But it's still just a guess, even if correct, until I can test that with a visit to your home. And given that this is a conversation on a wiki where we're responding probably days if not weeks separated, there's the challenge of even having the same people reading this text. We're well open to thought but ideas... ideas are easy. Science, that's hard.