One such mystery, described in a recent paper in The Astrophysical Journal Letters, concerns circumbinary exoplanets—or rather, the shortage thereof—in the now 6,000+ exoplanets confirmed to date.

For more than a century, Einstein’s relativity has set a hard speed limit for the universe, with light as the ultimate ...

This puzzle is known as the problem of time, and it remains one of the most persistent obstacles to a unified theory of ...

Time feels like the most basic feature of reality. Seconds tick, days pass and everything from planetary motion to human memory seems to unfold along a single, irreversible direction. We are born and ...

For those who watch gravitational waves roll in from the universe, GW250114 is a big one. It's the clearest gravitational ...

Gravity is invisible, yet it governs the cosmos, warping spacetime and bending light. This video explores Einstein’s general ...

A newly detected gravitational wave, GW250114, is giving scientists their clearest look yet at a black hole collision—and a powerful way to test Einstein’s theory of gravity. Its clarity allowed ...

Ahead of the launch of Artemis II, the first crewed mission to the moon in more than 50 years, astronauts share the movies that capture the danger, teamwork, and wonder of spaceflight. Their picks ...

Learn why only 14 out of over 6,000 exoplanets orbit two stars, and how Einstein’s general theory of relativity may be to blame.

Astronomers have found thousands of exoplanets around single stars, but few around binary stars—even though both types of stars are equally common. Physicists can now explain the dearth.