Einsteinium
Synthetic element discovered in hydrogen bomb debris.
Einsteinium is a synthetic chemical element with symbol Es and atomic number 99, a member of the actinide series and the seventh transuranium element.
- discovered_by
- Albert Ghiorso, Glenn T. Seaborg, and co-workers at University of California, Berkeley, in collaboration with Argonne and Los Alamos National Laboratories
Lore & Background
Seaborg, and co-workers at University of California, Berkeley in collaboration with the Argonne and Los Alamos National Laboratories, in the fallout from the Ivy Mike nuclear test. Initial examination of the debris showed the production of a new isotope of plutonium, 244Pu, which indicated that still more neutrons could have been captured by uranium, producing new elements heavier than californium. Ghiorso and co-workers analyzed filter papers flown through the explosion cloud on airplanes. Larger amounts of radioactive material were later isolated from coral debris of the atoll. The separation of suspected new elements was carried out using ion exchange at elevated temperatures; fewer than 200 atoms of einsteinium were recovered. Element 99, einsteinium, and in particular 253Es, could be detected via its characteristic high-energy alpha decay at 6.6 MeV. The discovery of the new elements was initially kept secret on the orders of the U.S.
Reader's Guide
Its discovery provided direct experimental confirmation of the r-process multi-neutron absorption needed to explain the cosmic nucleosynthesis of certain heavy elements in supernovas. Due to the small amounts produced and the short half-life of its most common isotope, there are no practical applications for einsteinium except basic scientific research. Like all synthetic transuranium elements, isotopes of einsteinium are very radioactive and are considered highly dangerous to health on ingestion.
Frequently Asked Questions
What is Einsteinium?
Einsteinium is a synthetic, radioactive element carrying the symbol Es and atomic number 99. It sits within the actinide series and is counted as the seventh transuranium element.
Who discovered Einsteinium?
Albert Ghiorso, Glenn T. Seaborg, and their co-workers at the University of California, Berkeley made the identification. They collaborated with teams at Argonne and Los Alamos National Laboratories to confirm the new element.
Is Einsteinium found naturally on Earth?
No—Einsteinium is entirely synthetic and has no natural occurrence. It must be created artificially, either as a trace byproduct of nuclear explosions or through sustained reactor irradiation.
More in Periodic Table & Elements 1-21
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