- Gacrux (stars.astro.illinois.edu)
GACRUX (Gamma Crucis). In our “western” star lore, the stars with proper names come from the set that could be seen from the lands of the ancient middle east and Arabia, and do not include those of the far southern hemisphere, which is largely invisible below the horizon from northern lands. Yet those who needed the stars to find their way, the old navigators, also needed quick names for some of the stars and just made them up. “Gacrux” is a prime example of such a star, its name deriving strictly from its Greek letter name, Gamma Crucis, the third-brightest star in the constellation Crux, the Southern Cross.
- Neptune (Wikipedia)
Neptune is the eighth planet from the Sun and the farthest known planet in the Solar System. It is the fourth-largest planet in the Solar System by diameter, the third-most-massive planet, and the densest giant planet. It is 17 times the mass of Earth, and slightly more massive than its near-twin Uranus. Neptune is denser and physically smaller than Uranus because its greater mass causes more gravitational compression of its atmosphere. Being composed primarily of gases and liquids, it has no well-defined solid surface. The planet orbits the Sun once every 164.8 years at an average distance of 30.1 astronomical units (4.5 billion kilometres; 2.8 billion miles). It is named after the Roman god of the sea and has the astronomical symbol ♆, representing Neptune’s trident.