December 21: The day an element was discovered that changed cancer treatment forever5 min read
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December 21 is an important date in history. A husband and wife duo made a crucial and remarkable discovery of an element that pushed the two to fame, even getting them the prestigious Nobel Prize.
Can you guess what element this was? It’s symbol is:
Ra
The atomic number of this element is 88.
If you guess Radium, you are absolutely right!
Now, do you know the famous couple that made this discovery? Unscramble the jigsaw below for a reveal.
It’s the Curies! Marie and Pierre Curie were the famous couple who dedicated their lives to science!



Photo: nobel.org
In 1896, Henri Becquerel, a French engineer, physicist, Nobel laureate, and the first person to discover evidence of radioactivity, was studying uranium when he discovered a new type of radiation that could pass through metal. His research got the attention of physicist Marie Curie, who began to study these uranium rays.
She soon made a revolutionary discovery when she determined that the ability to radiate did not depend on the arrangement of the atoms in a molecule, but on the interior of the atom.
Marie was joined by her physicist husband Pierre to study uraninite, then known as pitchblende, a uranium-rich mineral and ore. The pair removed uranium and were left with a radioactive material they determined should be two new elements, radium and polonium.

They first discovered polonium, named for Marie’s homeland Poland, in July 1898. In documenting their work they wrote, “We thus believe that the substance that we have extracted from pitchblende contains a metal never known before, akin to bismuth in its analytic properties.” The substance was about 300 times more active than uranium. In this paper, the pair also used the term radioactivity for the first time.
Later that year, on December 21, 1898, the Curies found radioactive compounds similar to barium compounds that became a new element they named radium because of the way it emitted energy in rays. They measured radium’s intensity at around 3,000 times that of uranium. Marie Curie received the Nobel Prize in Chemistry 1911 for the discovery of the elements radium and polonium. She became the first women ever to receive the prestigious award!
The discovery of radium allowed for radiotherapy and nuclear medicine, which changed the treatment of cancer and other diseases. As early as 1899, it was reported that a dangerous tumour of the skin was cured by radioactive source application.
The dangers of radiation….

The detrimental effects of radiation were not immediately known, and the research took its toll on the Curies’ health. Use of radium in everyday life, including its use in luminous paint to create watches that would glow in the dark, led to the discovery of radiation poisoning. Marie died in 1934 from aplastic anemia, likely caused by her exposure to radiation. The pair’s laboratory notes are still radioactive and have to be stored in lead boxes, and Marie’s coffin was lined with lead.
Radium now has few uses, because it is so highly radioactive. Radium-223 is sometimes used to treat prostate cancer that has spread to the bones. Because bones contain calcium and radium is in the same group as calcium, it can be used to target cancerous bone cells! Radium used to be used in luminous paints, for example in clock and watch dials. It is now considered to be too hazardous to be used in this way.
Owliver’s Obscure Observations
Marie Curie’s daughter Irene won the Nobel Prize in chemistry in 1935. This made them the first mother-daughter duo to win the prize.
5 facts about Marie Curie:
1. Her parents were teachers, so education was important in their family.
2. She’s the only person to win Nobel prizes in two separate sciences — physics and chemistry.
3. She added two elements to the periodic table.
4. She did her most important work in a shed, as women being in the sciences and in laboratories was frowned upon back then!
5. Her notebooks are still radioactive and are sealed with lead!

Who are some scientists you admire and why? Comment below and let us know!
Sources: India Today, Britannica, Wired