The giant planets weren't always where we find them today. Jupiter, Saturn, Uranus and Neptune formed in a more compact ...

Even the best telescopes can’t see exoplanets. It’s all about watching for jiggly stars, blue shifts, and transits.

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

Before 3I/ATLAS, the only other confirmed interstellar tourists we've seen were the now-famous, cigar-shaped 'Oumuamua' in ...

Interstellar comet 3I/ATLAS makes its closest Earth approach on Dec. 19, offering astronomers a rare chance to study a visitor from beyond the solar system ...

The comet will come much closer to Jupiter in March, zipping within 33 million miles. It will be the mid-2030s before it ...

Comet 3I/ATLAS will get closest to Earth on Dec. 19, and astronomers will be watching.

Interstellar object 3I/ATLAS is making its closest approach to Earth in just over a week from now, coming within 167 million ...

Interstellar object 3I/ATLAS is baffling astronomers with its bizarre, sun-facing anti-tail, confirmed by Hubble.

Interstellar object 3I/ATLAS continues to display a Sun-facing anti-tail, confirmed by Hubble, Gemini and XMM-Newton ...

Interstellar object 3I/ATLAS nears Earth, showing a rare anti-tail, changing brightness, and new clues about its origin, with ...

Oumuamua, the first known interstellar object, passed through our solar system in 2017, sparking debates and curiosity among ...