If intelligent aliens exist, why haven't we seen them?

Thousands of planets have been discovered in the last few decades, although astronomers tell us there are probably billions. In such a large and diverse set of solar systems, it seems impossible that humans could be the only ...

Supercomputer turns back cosmic clock

Astronomers have tested a method for reconstructing the state of the early universe by applying it to 4000 simulated universes using the ATERUI II supercomputer at the National Astronomical Observatory of Japan (NAOJ). They ...

page 9 from 40