Shell star Shell star A shell star is a star having a spectrum that shows extremely broad absorption lines, plus some very narrow absorption lines. They typically also show some emission lines, usually from the Balmer series but occasionally of other lines. The broad absorption lines are due to rapid rotation of the photosphere, the emission lines from an equatorial disk, and the narrow absorption lines are produced when the disc is seen nearly edge-on. Shell stars have spectral types O7.5 to F5, with rotation velocities of 200–300 km/s, not far from the point when the rotational acceleration would disrupt the star.
Given name Given name A given name (also known as a first name, forename or Christian name) is a part of a person's personal name. It identifies a specific person, and differentiates that person from the other members of a group (typically a family or clan) who have a common surname. The term "given name" refers to the fact that the name usually is bestowed upon a person, normally to a child by his or her parents at or close to the time of birth. A Christian name, a first name which historically was given at baptism, is now also typically given