It takes approximately 0.134 seconds to travel around the Earth at the speed of light.

Here's how to calculate that:

* Earth's circumference: 40,075 kilometers (24,901 miles)

* Speed of light: 299,792,458 meters per second

Calculation:

1. Convert Earth's circumference to meters: 40,075 km * 1000 m/km = 40,075,000 meters

2. Divide the circumference by the speed of light: 40,075,000 m / 299,792,458 m/s = 0.1336 seconds

Important Note: This is just a theoretical calculation. It's impossible for anything with mass to reach the speed of light.