The Prime Meridian

The Prime Meridian

The Earth rotates 360 degrees in 24 hours. That means it turns 15 degrees every hour. If you know the exact time at a reference location — and compare it to your local time — you can calculate your longitude. But that requires extraordinary precision. In the eighteenth century, an English clockmaker named...
Space-time

Space-time

What if I told you that right now, you're surfing through a four-dimensional ocean that can stretch, compress, and ripple like water? Meet spacetime—the invisible fabric that Einstein discovered controls…