A planet’s opposition occurs when Earth passes between it and the Sun. As a consequence of that geometry, Neptune’s disk will appear to be 100% illuminated as seen from Earth. It will be 180º ...

The perception of Neptune as much darker and bluer than Uranus was "cemented" when pictures were sent back by the Voyager 2 probe after it flew by the two planets in 1986 and 1989, said The Times.

NASA’s Voyager mission completed humankind’s first close-up exploration of the four giant outer planets of our solar system.

The images shows bright cirrus clouds high in its atmosphere above most of its methane. It had been thought that the clouds were a product of seasons on Neptune, each of which last about 41 Earth ...

Look for a planetary parade that includes Mars, Jupiter, Uranus, Neptune, Venus ... which is the imaginary plane containing the Earth's orbit around the Sun. The other planets travel along ...