Buzz
Einsteinium was first identified by Albert Ghiorso, a nuclear scientist involved in the Manhattan Project, following the explosion of the hydrogen bomb "Ivy Mike" in 1952. Bettmann/Contributor/Getty ImagesOn November 1, 1952, U.S. military scientists activated a peculiar three-story device codenamed "Ivy Mike," marking the detonation of the world's first hydrogen bomb. This revolutionary weapon was 700 times more potent than the atomic bombs used in Japan.
The test occurred on Eniwetok, a small atoll in the Marshall Islands of the South Pacific. Ivy Mike unleashed 10.4 megatons of energy, equivalent to 10.4 million tons of TNT. In contrast, the Hiroshima bomb released only 15 kilotons (15,000 tons of TNT).
The detonation completely obliterated the Eniwetok atoll, generating a mushroom cloud spanning 3 miles (4.8 kilometers). Clad in protective gear, workers collected fallout from a nearby island and transported it to Berkeley Lab in California (now known as the Lawrence Berkeley National Laboratory) for examination. There, a group of Manhattan Project scientists, headed by Albert Ghiorso, successfully isolated just 200 atoms of a new element with 99 protons and 99 electrons.
In 1955, the team revealed their groundbreaking discovery to the public, naming the element einsteinium in honor of their scientific idol.
Big and Unstable
Einsteinium is positioned at atomic number 99 on the periodic table, alongside other heavy, radioactive elements such as californium and berkelium. While some radioactive elements like uranium are found naturally in Earth's crust (with uranium being more abundant than gold at 2.8 parts per million), heavier elements like einsteinium can only be synthesized artificially, either through hydrogen bomb explosions or particle collisions in reactors.
What causes an element to be radioactive? For einsteinium and its counterparts at the lower end of the periodic table, it's the enormous size of their atoms, according to Joseph Glajch, a pharmaceutical chemist with extensive experience in medical imaging using radioactive elements.
"When atoms reach a certain size, their nucleus becomes unstable and begins to break apart," explains Glajch. "This process involves emitting neutrons, protons, or electrons, causing the element to decay into a more stable form."
During radioactive decay, elements release clusters of subatomic particles, such as alpha particles, beta particles, and gamma rays. While some forms of radiation are relatively benign, others can cause significant harm to human cells and DNA.
A Short 'Shelf Life'
Radioactive decay also produces various isotopes, each with distinct atomic weights. The atomic weight is determined by combining the number of protons and neutrons in the nucleus. For instance, the einsteinium-253 isotope, identified in the South Pacific in 1952, contains 99 protons and 154 neutrons.
Isotopes are not permanent; each has a unique half-life, representing the time it takes for half of the material to decay into a different isotope or element. Einsteinium-253 has a remarkably short half-life of just 20.5 days. In contrast, uranium-238, the most abundant uranium isotope in nature, has a half-life of 4.46 billion years.
Producing heavy radioactive elements like einsteinium in specialized nuclear reactors is challenging because these large elements begin to decay almost immediately after creation.
"The larger the elements and isotopes you create, the harder it becomes to observe them before they decay," explains Glajch.
At Berkeley Lab, scientists Jennifer Wacker, Leticia Arnedo-Sanchez, Korey Carter, and Katherine Shield handle radioactive einsteinium samples under fume hoods in Rebecca Abergel's chemistry lab.
Marilyn Sargent/Berkeley LabBig Breakthrough on a Small Scale
The chemistry community recently celebrated a significant breakthrough when researchers managed to stabilize a sample of short-lived einsteinium long enough to study its chemical properties, sparking widespread enthusiasm.
Led by Rebecca Abergel of the Lawrence Berkeley National Laboratory, the team awaited a minuscule sample of einsteinium-254, weighing just 250 nanograms, from the Oak Ridge National Laboratory in Tennessee. With a half-life of 276 days, the research faced delays during the COVID-19 pandemic, during which 7 percent of the sample decayed every month.
Abergel achieved a major milestone by developing a molecular "claw" capable of securing a single atom of einsteinium-254. This allowed the team to measure key properties, such as molecular bond lengths and light emission wavelengths, which are vital for exploring potential applications like cancer therapy.
Albert Ghiorso, a nuclear scientist, co-discovered a record-breaking 12 elements, including einsteinium, through his pioneering radiation analysis work from the 1950s to the 1970s.
