3I/ATLAS has now made its closest approach to the sun and Earth and is now heading back out toward the outer solar system. On ...

I/ATLAS has passed its closest point to Earth, meaning we will soon lose sight of it for good. Some scientists want to send a spacecraft to chase down the alien comet — or the next interstellar object ...

Interstellar comet 3I/ATLAS makes its closest approach to Earth on Dec. 19. Here's how you can track its progress both during ...

The comet is the third object ever confirmed to have entered our cosmic neighborhood from elsewhere in the galaxy. Space ...

The universe is supposed to look the same no matter where you stand. That idea, known as the cosmological principle, sits at the heart of modern astrophysics. It says matter spreads out evenly when ...

The latest visitor from deep space is leaving a mark that stretches far beyond its icy core. Interstellar comet 3I/ATLAS is wrapped in an enormous X-ray glow that extends roughly 250,000 miles into ...

After less than a year in orbit, the Southwest Research Institute-built PUNCH spacecraft have made major accomplishments, ...

How fast and in which direction is our solar system moving through the universe? This seemingly simple question is one of the key tests of our cosmological understanding. A research team led by ...

Astronomers are uncovering distant worlds beyond our solar system using ingenious indirect methods like observing stellar ...