Breakthroughs, discoveries, and DIY tips sent six days a week. Terms of Service and Privacy Policy. Back in 2018, astronomers examining the ruins of two collided ...

Scientists pushed photons across the universe to test the speed of light—and found Einstein’s cosmic speed limit still holds ...

The Parker Solar Probe, currently the fastest human-made object, travels at 0.05% the speed of light (approximately 330,000 mph). Reaching 1% the speed of light requires an immense amount of energy ...

We wouldn’t notice. Or we’d die. Depends on how much it changed. Relativity already tells us what would happen if the speed of light were to change, and the answer is nothing. Consider a stationary ...

On one hand, the speed of light is just a number: 299,792,458 meters per second. And on the other, it’s one of the most important constants that appears in nature and defines the relationship of ...

Light is fast. In fact, it is the fastest thing that exists, and a law of the universe is that nothing can move faster than light. Light travels at 186,000 miles per second (300,000 kilometers per ...

Chris Impey receives funding from the National Science Foundation and the Hearst Foundation. Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, ...