Oh, we humans do love a cleanly defined boundary, don’t we? They make things easier, after all. If we’re trying to categorize something, knowing what labeled bin to put it in is handy. If we’re ...

Our solar system is a smashing success. A new study suggests that from its earliest period—even before the last of its nebular gas had been consumed—Earth's solar system and its planets looked more ...

Voyager 1, launched in 1977, has traveled farther than any spacecraft in human history. After more than four decades of silent endurance through space, it now sails beyond the orbit of the outer ...

The search for an unknown planet in our solar system has inspired astronomers for more than a century. Now, a recent study suggests a potential new candidate, which the paper’s authors have dubbed ...

Astronomers found that interstellar object 3I/ATLAS shows an "extreme abundance ratio" of nickel and iron in its gas plume. Astronomers are still poring over data to get a better sense of 3I/ATLAS, ...

Portal’s heat exchanger thruster, known as Flare, fires up during a test in a vacuum chamber. (Portal Space Systems Photo) Bothell, Wash.-based Portal Space Systems says it has successfully tested its ...

NASA is tracking an object that is entering the solar system at approximately 245,000 km/h. This interstellar visitor is 3I/ATLAS, also known as “Comet C/2025 N1 (ATLAS) and initially dubbed A11pl3Z.

While many dream of bases on Mars and cities above Venus, the reality of colonizing the Solar System is far more difficult and may be impossible with today’s technology. NATO scrambles fighter jets as ...

In 1977, the Ohio State University’s Big Ear radio telescope received an unusually strong narrowband radio signal, leading to widespread excitement about the possibility of having encountered evidence ...

Titan, the second largest moon in the Solar System—indeed, it is even larger than the planet Mercury—draws attention not only because of its size, but also due to its dense, hazy atmosphere, an ...

It's probably a comet, but it might be some sort of ancient alien spacecraft or probe. What's for sure is that the mystery surrounding an object known as 3I/ATLAS is becoming both more and ...