Whether you are the one leaving or the one being left behind, maintaining a romantic relationship long-distance can be a challenge for even the strongest of couples. Time differences, busy schedules ...

Interstellar comet 3I/ATLAS made its closest approach to Earth early on Friday, Dec. 19. While it didn't come close enough to ...

Whether you’re a new runner or an experienced one, the stride length you naturally choose is likely your most efficient, ...

When is winter? Weather forecasters in the Northern Hemisphere will tell you Dec. 1 through the end of February, which is ...

Ask a runner how many miles they run each week, and you will likely get a range: seven to 10 or 15 to 25, for example. That’s because the answer depends on a few details, such as whether you’re ...

The acceleration principle is an economic concept that attributes fluctuations in capital investment to changes in consumer demand.

The speed at which glaciers move changes predictably each year, according to the first-ever global map of how glacier and ice sheet speeds vary with the seasons. Knowing this yearly rhythm could help ...

A version of this story appears in the September 2020 issue of National Geographic magazine. Philadelphia detected its first case of a deadly, fast-spreading strain of influenza on September 17, 1918.

The M.T.A.’s new “Love Letter to the Subway” tells all about the underground system beloved—and hated—by New Yorkers.

See how your savings and investment account balances can grow with the magic of compound interest. Many, or all, of the products featured on this page are from our advertising partners who compensate ...

Here’s what you’ll learn when you read this story: For more than 50 years, scientists theorized that an electromagnetic wave could be reflected temporally—not just spatially. Scientists have been ...

Codes you redeem vary in their rewards, from in-game currency (like uCoins) to skin crates. That’s why it’s important you collect any free gifts for A Universal Time as soon as possible. Codes for ...