Einsteinium is a synthetic element with the symbol Es and atomic number 99. It was discovered in 1952 as a byproduct of the first hydrogen bomb explosion, known as Ivy Mike. Einsteinium is part of the actinide series and is classified as a heavy metal. It is highly radioactive and has no significant commercial applications, primarily used for research purposes. This element is named after the famous physicist Albert Einstein. Einsteinium is produced in minute quantities in nuclear reactors and is primarily studied for its properties and potential uses in nuclear science. Its most stable isotope, Es-252, has a half-life of about 471.7 days.