Make sure your angles are in units of radians (not degrees), where 2π radians = 360 degrees. But after that you will get the ...

It takes light a single day to travel 16 billion miles. The Voyager 1 probe will need a little longer, just 49 years.

In the middle of a chilly October night in 2025, my two friends and I suited up at the Cottonwood Creek trailhead and started ...

In the leading model of cosmology, most of the universe is invisible: a combined 95% is made of dark matter and dark energy.

For centuries, scientists have tried to measure the speed of light directly and failed every single time. Light moves so fast ...

Astronomers capture the twinkle of a distant quasar, RX J1131, and reveal the secret size of a black hole's fiery corona.

The Moon is getting 1½ inches (3.8 centimeters) farther away from the Earth every year. Scientists measure the distance to ...

New details from the Webb telescope indicate there might be a fundamental problem with our understanding of the universe. The spiral galaxy NGC 4258, imaged by the Hubble Space Telescope, measures ...

The holidays seem to arrive earlier every year. Halloween hadn’t ended when red and green invaded every aisle, and though the ...

Voyager 1 is about to cross a threshold that sounds almost mythical: within about a year, the spacecraft will be a full light ...

When you’re ready to run faster for longer than a mile, you’re ready to try a tempo run. Tempo efforts are “comfortably hard.” Physically, they teach your body to become more efficient at running at a ...