1666: "A Billion Seconds"

1672: "Magnetism is a Relativistic Force"

Interesting Things with JC #1672: "Magnetism is a Relativistic Force" – A current-carrying wire stays electrically neutral on a table while a moving charge beside it feels a magnetic force, but in the charge’s own frame the spacing of charges changes and the same force appears electric.

1671: "What Is the L2 Point?"

Interesting Things with JC #1671: "What Is the L2 Point?" – A mathematician identified a location in space in 1772 where gravity keeps spacecraft moving with Earth around the Sun, and nearly 250 years later observatories began traveling there to do some of humanity's most advanced science.

1670: "Napster"

Interesting Things with JC #1670: "Napster" – On June 1, 1999, Shawn Fanning releases Napster, and within months college students are searching each other’s hard drives for MP3 files while campus networks slow under traffic and the music industry moves toward court.

1669: "The Rare Blue Moon"

Interesting Things with JC #1669: "The Rare Blue Moon" – A second full Moon rises over May, carrying a rare name it will not appear to deserve. It will not look blue, and it may look completely ordinary, but the calendar has left room for one extra full Moon while the Moon itself is near the farthest edge of its orbit.

1668: "History of the Stanley Cup"

Interesting Things with JC #1668: "History of the Stanley Cup" – The Stanley Cup keeps changing hands while its silver bands record winners, mistakes, and accidents. A trophy meant for amateur hockey becomes the NHL championship prize, then survives misspellings, stolen time as a flower vase, hidden names, fires, dogs, babies, and fingerprints.