- Gnathostomata (Wikipedia)
Gnathostomata (/ˌnæθoʊˈstɒmətə/; from Ancient Greek: γνάθος (gnathos) ‘jaw’ + στόμα (stoma) ‘mouth’) are the jawed vertebrates. Gnathostome diversity comprises roughly 60,000 species, which accounts for 99% of all living vertebrates, including humans. In addition to opposing jaws, living gnathostomes have true teeth (a characteristic which has subsequently been lost in some), paired appendages (pectoral and pelvic fins, arms, legs, wings, etc.), the elastomeric protein of elastin, and a horizontal semicircular canal of the inner ear, along with physiological and cellular anatomical characters such as the myelin sheaths of neurons, and an adaptive immune system that has the discrete lymphoid organs of spleen and thymus, and uses V(D)J recombination to create antigen recognition sites, rather than using genetic recombination in the variable lymphocyte receptor gene.
- Messier 26 (Wikipedia)
Messier 26, also known as NGC 6694, is an open cluster of stars in the southern constellation of Scutum. It was discovered by Charles Messier in 1764. This 8th magnitude cluster is a challenge to find in ideal skies with typical binoculars, where it can be, with any modern minimum 3-inch (76 mm) aperture device. It is south-southwest of the open cluster Messier 11 and is 14′ across. About 25 stars are visible in a telescope with a 150–200 mm (6–8 in) aperture.
