- Alphard (stars.astro.illinois.edu)
ALPHARD (Alpha Hydrae). Not all that well known among bright stars, but surprisingly prominent, Alphard both dominates and lies at the heart of the relatively dim constellation Hydra, the Water Serpent (the longest constellation of the sky), hence clearly deserves to be Bayer’s Alpha star.
- Ring Nebula (Wikipedia)
The Ring Nebula (also catalogued as Messier 57, M57 and NGC 6720) is a planetary nebula in the northern constellation of Lyra. Such a nebula is formed when a star, during the last stages of its evolution before becoming a white dwarf, expels a vast luminous envelope of ionized gas into the surrounding interstellar space.
