- Star Tales combines Corvus and Crater on a single page
- Observable universe (Wikipedia)
The observable universe is a ball-shaped region of the universe comprising all matter that can be observed from Earth or its space-based telescopes and exploratory probes at the present time; the electromagnetic radiation from these objects has had time to reach the Solar System and Earth since the beginning of the cosmological expansion. Initially, it was estimated that there may be 2 trillion galaxies in the observable universe. That number was reduced in 2021 to only several hundred billion based on data from New Horizons. Assuming the universe is isotropic, the distance to the edge of the observable universe is roughly the same in every direction. That is, the observable universe is a spherical region centered on the observer. Every location in the universe has its own observable universe, which may or may not overlap with the one centered on Earth.
- Star Tales - Corvus and Crater (ianridpath.com)
These two adjacent constellations are linked in a moral tale that goes back at least to the time of Eratosthenes in the third century BC. As told by Ovid in his Fasti, Apollo was about to make a sacrifice to Zeus and sent the crow to fetch water from a running spring. The crow flew off with a bowl in its claws until it came to a fig tree laden with unripe fruit. Ignoring its orders, the crow waited several days for the fruit to ripen, by which time Apollo had been forced to find a source of water for himself.