1672: "Magnetism is a Relativistic Force"

1673: "There Is No Universal Now"

Interesting Things with JC #1673: "There Is No Universal Now" – A star 100 light-years away is doing something at this moment, but observers moving at different velocities can assign different times to the same distant event. What appears simultaneous to one observer does not appear simultaneous to another, and the universe continues without a single present moment everyone shares.

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.