What highly ionised elements are found in the spectrum of WR 102c?
WR 102c WR 102c is a Wolf–Rayet star located in the constellation Sagittarius towards the galactic centre. It is only a few parsecs from the Quintuplet Cluster, within the Sickle Nebula.
Francium Francium is a chemical element with symbol Fr and atomic number 87. It used to be known as eka-caesium and actinium K. It is the second-least electronegative element, behind only caesium, and is the second rarest naturally occurring element (after astatine). Francium is a highly radioactive metal that decays into astatine, radium, and radon. As an alkali metal, it has one valence electron.