- Star Tales - Sagitta (ianridpath.com)
Sagitta, the third-smallest constellation in the sky, has no stars brighter than fourth magnitude, but it was well-known to the Greeks and was among the 48 constellations listed by Ptolemy in the Almagest. Aratus described it as ‘alone, without a bow’ since there is no sign of the archer who might have shot it.
- Feldspar (Wikipedia)
Feldspar (/ˈfɛl(d)ˌspɑːr/ FEL(D)-spar; sometimes spelled felspar) is a group of rock-forming aluminium tectosilicate minerals, also containing other cations such as sodium, calcium, potassium, or barium. The most common members of the feldspar group are the plagioclase (sodium-calcium) feldspars and the alkali (potassium-sodium) feldspars. Feldspars make up about 60% of the Earth’s crust, and 41% of the Earth’s continental crust by weight.