Eta Cassiopeiae A (also known as Achird) is a nearby yellowish-white star located in the constellation Cassiopeia. It is bright enough to be seen with the naked eye. It is slightly larger, hotter, and more luminous than our Sun, but it has a lower abundance of elements heavier than helium. The star is the dominant member of a binary system that also includes a smaller orange dwarf star, Eta Cassiopeiae B. This system has an eccentric orbit, bringing the stars as close as Neptune to the Sun an…