The third known visitor from another star system, Comet 3I/ATLAS, has been racing through the Solar System with just enough weirdness to ignite a familiar debate: is it natural or could it be ...

For generations, humans have imagined what it would be like to discover life beyond Earth. Would alien beings look anything like us? Would they communicate through sounds, signals, or something ...

Even at this early stage in our spacefaring age, humanity has already begun sending probes that will eventually reach other solar systems, even if that was not their original intention. Five robotic ...