Growing up in the icy isolation of Hibbing, Minn., Dylan, who was still Robert Allen Zimmerman then, found comfort in the country, blues, and early rock 'n' roll that he heard at night on a Louisiana radio station whose signal came in strong and clear.

In the role of Ziggy Stardust, Bowie seemed in 1972 like a strange alien creature, not so much coming from another planet as from a future age. His purpose: to warn us about a dangerous society where values were to be turned inside out.

I was getting calls in 1970 from teenagers, little girls, and they'd say, 'Oh, I like your stories about so-and-so so much. How old are you? 20?' 'No. Older than that.' '30?' 'No. Older than that.' And they'd hang up.

The greatest impact of 'We Are the World' seems to have been the video, which lets us see the singers take their turns at the microphone without any sense of star ego.

I expect Congress to continue to work on that, to secure the border, to invest in smart technology, and in personnel that makes a difference there.

Even as technology becomes increasingly critical to the way we live our lives, power our world and defend our shores, the United States has allowed the production of minerals crucial in the creation of these advanced products to slide.

Sometimes I worry that science communication is just preaching to the choir, speaking to the converted. Social media gives us an amazing opportunity to reach new people.

The Internet has empowered us. It has empowered you, it has empowered me, and it has empowered some other guys as well.