- Pale Blue Dot (Wikipedia)
Pale Blue Dot is a photograph of Earth taken on February 14, 1990, by the Voyager 1 space probe from an unprecedented distance of approximately 6 billion kilometers (3.7 billion miles, 40.5 AU), as part of that day’s Family Portrait series of images of the Solar System.
- Class (biology) (Wikipedia)
In biological classification, class (Latin: classis) is a taxonomic rank, as well as a taxonomic unit, a taxon, in that rank. It is a group of related taxonomic orders. Other well-known ranks in descending order of size are life, domain, kingdom, phylum, order, family, genus, and species, with class ranking between phylum and order.