April 22 is Rita Levi-Montalcini’s birthday. Levi-Montalcini was an Italian neurologist who made several discoveries of how cells divide and form new cells with different functionality.
Levi-Montalcini began her career in science wanting to be a doctor. She graduated with an M.D. from the University of Turin in 1936 and took a position as a research assistant studying the development of the nervous system. This position did not last long after Mussolini passed laws prohibiting Jews from academic and professional careers. Instead of working at the University, she set up her own laboratory in her bedroom studying nerve cell development in chicken embryos.
After the war, she got a research fellowship at Washington University in St. Louis. She reproduced her chicken embryo experiments and struck up a relationship with the university that would last 30 years. During this time, one of her experiments involved transferring tumors to chick embryos and noticing how quickly the nerve fibers grew around the tumors. This led her to the discovery and isolation of the nerve growth factor NGF. This discovery would lead to other growth factor discoveries and helped scientists gain an understanding of medical problems such as cancer, deformities, and dementia. It also earned her half of the 1986 Nobel Prize in Medicine.
Levi-Montalcini divided her time between St. Louis and a second laboratory she set up in Rome. After retiring, she served as director of the Institute of Cell Biology in Italy and founded the European Brain Research Institute. In 2001, she was appointed Senator for Life to the Italian Senate by President Ciampi. She remained active in Italian politics until her death in 2012 at age 103.
Notable Science History Events for April 22
1989 – Emilio Segré died.
Segré was an Italian physicist who discovered the first man-made element, technetium and the element of astatine. He was also awarded the 1959 Nobel Prize in Physics with Owen Chamberlain for their discovery of the antiproton, or negatively charged proton.
Find out more about Segré on February 1 in Science History.
1980 – Fritz Strassmann died.
Strassman was a German chemist who with Otto Hahn identified the smaller element barium when uranium was bombarded by neutrons leading to the discovery of the process of nuclear fission.
1970 – First Earth Day celebrated.
Earth Day was first celebrated in the United States to raise awareness of environmental issues. The first Earth Day was concerned with over-population and the stresses it creates and the problems of global cooling.
Today Earth Day is celebrated with events in nearly 200 countries around the world.
1952 – First televised atomic bomb test.
The United States detonated the Tumbler Charlie atomic bomb at Yucca Flats at 9:30 am and allowed it to be televised to a nationwide audience.
The test was the highest air burst up to that time with a predicted yield of 31 kilotons. The 10,440 lb (4735.5 kg) bomb was dropped from a B-50 Superfortress bomber. This bomb contained a new high-efficiency core and the drop was designed to measure the blast effects and act as a proof of concept.
1919 – Donald J. Cram was born.
Cram was an American chemist who shares with Jean-Marie Lehn and Charles Pedersen the 1987 Nobel Prize in Chemistry for their research and development of host-guest chemistry. Host-guest chemistry is where two or more molecules/ions bond in unique ways due to their structure in other than covalent bonds.
1915 – Modern chemical weapons first used.

Modern chemical weapons were first used when German troops released over 150 tons of chlorine gas during the Second Battle of Ypres in Belgium. The green gas was blown over French trenches and killed 5000 soldiers.
Gas attacks would grow more sophisticated throughout the war and would cause an estimated 88,000 deaths and 1.2 million non-fatal victims on both sides by the end of the war.
1909 – Rita Levi-Montalcini was born.
1904 – J. Robert Oppenheimer was born.
Oppenheimer was the American physicist who was the lead researcher for the Manhattan Project, and is considered the ‘father of the atomic bomb’.
After the war, Oppenheimer served as the chairman of the General Advisory Committee of the new US Atomic Energy Commission. He used this platform to lobby against nuclear proliferation and control of nuclear power. This position did not stand well with the 1950s political scene. He was stripped of his security clearance and basically ended his public work.
1891 – Harold Jeffreys was born.
Jeffreys was an English mathematician, geophysicist, and astronomer who was first to propose the Earth’s core was molten. He also calculated the surface temperatures of the outer planets to be very cold instead of very hot, as prevailing science predicted.
1876 – Robert Bárány was born.
Barany was a Hungarian physician who was awarded the 1914 Nobel Prize in Medicine for his research on the vestibular apparatus of the inner ear. The vestibular apparatus aids us with our balance and sense of spatial orientation by sending the brain information to aid eye-hand coordination and keeping us standing upright.
1839 – August Wilhelm Eichler was born.
Eichler was a German botanist who created one of the first plant classification systems. He divided plants into four phyla: Thallophyta, Bryophyta, Pteridophyta, and Spermatophyta.
1056 – Final observation of the Crab Nebula supernova recorded.
A Chinese astronomer recorded the ‘guest star’ in the constellation of Taurus became invisible. The ‘guest star’ was a supernova event first seen on July 5, 1054, and increased in brightness up to four times the brightness of Venus and visible in the day sky. This supernova created a radio pulsar and the surrounding Crab Nebula.