Bill Nye was on CNN recently discussing the age of the earth, and how science knows it’s 4.5 billion years old.
You can click the screen captured image above to watch the interview. I suggest it.
He’s not saying anything new to anyone who reads about this stuff, but the discussion about the Dover trial is a bit nuanced.
I found this video at Pharyngula, and PZ gave a great explanation about the importance of bringing up the smoke detector.
Ionizing smoke detectors use a tiny amount of radiactive [sic] material to generate charged ions by their decay; these ions are released into the space in a capacitor, and their movement generates a constant trickle of current. If smoke particles enter the detector, they bind to the ions and block the current; that easily measured decline in current is what triggers the alarm in the detector.
This is a very simple system that depends entirely on our quantitative understanding of radioactivity. If radioactivity didn’t work like we thought it did, your smoke detector would not be very reliable, and for that matter, no one would have thought of using this function to work as a smoke detector.
Read more here.