New simulations suggest that up to four of the solar system's rocky planets, including Earth and a long-lost world, once ...

In our solar system, Mercury, Venus, Earth, and Mars have period ratios of about 2.6, 1.6, and 1.9, respectively. Overall, the study showed that our solar system fits reasonably well into the team ...

Scientists have thought that our solar system's inner rocky planets — Mercury, Venus, Earth and Mars —formed first (around 4.566 billion years ago), while gas giants and icy bodies in the ...

This mismatch “doesn’t mean it’s not there, but it means it’s not Planet 9,” Brown said. “I don’t think this planet would have any of the effects on the solar system that we think we ...

A new look through decades-old data has unveiled some of the most compelling evidence yet of a hidden ninth planet in the far reaches of our solar system, far beyond ...

The newborn planetary system appears to be emerging 1,300 light-years away around a baby star known as HOPS-315 that resembles a young version of the Earth's own sun. Using data from ground and ...

It Came From Outside Our Solar System, and It Looks Like a Comet 3I/ATLAS, earlier known as A11pI3Z, is only the third interstellar visitor to be discovered passing through our corner of the galaxy.