Einsteinium is a transuranium element, located in Row 7 of the periodic table. The elements that make up this family are also known as the actinides, after the first member of the family. Einsteinium's atomic number is 99, its atomic mass is 252.0828, and its chemical symbol is Es.

Properties

All isotopes of einsteinium are radioactive, the most stable being einsteinium-252 with a half life of 20.47 days. Too little of the element has been prepared thus far for scientists to have made determinations of its properties.

Occurrence and Extraction

Einsteinium does not occur naturally in the Earth's crust. Instead, it is prepared in particle accelerators by bombarding isotopes of heavy transuranium elements with alpha particles.

Discovery and Naming

Einsteinium was discovered in November 1952 at Eniwetok Atoll, Marshall Islands, in the Pacific Ocean as a byproduct of the first hydrogen bomb test. The element was produced in trace amounts during the explosion of that bomb. The research team that discovered the element was led by Albert Ghiorso, who has also been involved in the discovery of many other transuranium elements. The team chose to name the new element after the German-American physicist Albert Einstein (1879-1955), sometimes regarded as the greatest scientist who has ever lived.

Uses

Einsteinium is sometimes used for research purposes, but it has no practical applications.