96 Curious Marie Curie-High

Curious Marie Curie FOCUS Question How did Marie Curie expand our understanding of atoms and radiation?

Radiation All Around Ah... summertime! Swimming has made you chilly, so you let the sunlight warm you from head to toe. The Sun is extremely distant, yet your skin tingles with heat energy. What's the secret? The warmth you feel is due to radiation. Radiation is the movement of energy from one place to another. Solar radiation is light energy from the Sun, which converts to heat energy when it hits your skin, making you feel warm and tingly. But you don't have to travel into space to find other sources of radiation, because everything on Earth gives off some radiant energy. In fact, some of these sources radiate enough energy to power entire cities.

Nuclear power plants use the radiant energy found in atoms of uranium— a natural element found in the ground. This power is called nuclear because the energy comes from the atom's core, or nucleus. Uranium has the potential to produce about two million times as much energy as oil or coal. In 1897, French physicist Antoine Henri Becquerel discovered that uranium releases energy. However, another remarkable scientist, named Marie Curie, figured out how it gives off energy. She would completely change our understanding of atoms. She even discovered two new elements along the way. Do You Know? An atom of uranium can quickly release an enormous amount of energy and radiation. Some countries have used this power to create nuclear weapons.

Curious Marie Born in Poland in 1867, Maria Sklodowska loved science. Although most girls were not allowed to attend school at that time, her parents made sure Maria was educated. Maria's dream was to study science at Sorbonne University in Paris, France. It took hard work and patience to save enough money to go to France. Maria moved to Paris in 1891, changing her name to Marie to fit in. Even though she didn't speak French when she arrived, she graduated from Sorbonne at the top of her class in 1893. Still eager to learn, she continued her education. In 1903, she became the first woman in Europe to earn a Ph.D.— but her science honors had only just begun.

Atoms and Energy Marie began working with a physicist named Pierre Curie. They fell in love and married in 1895. Two years later, Becquerel discovered that uranium emits energy. Marie decided to figure out the mystery of how uranium worked. Uranium is found in ore— natural minerals in the ground. Marie learned that when greater amounts of uranium were present, an ore sample radiated more energy. Marie suggested that the energy must come from inside the uranium atoms themselves. If so, this would mean that atoms must have smaller parts inside that somehow emit, or give off, energy. No one had thought of this before, so her hypothesis alone was big science news!

New Elements Next, Curie separated the uranium from the ore. Surprisingly, she noticed that the ore was still releasing energy. She suggested that new elements within the ore could also radiate energy. Marie and Pierre used several tons of ore to collect enough of the new elements to study them. After four years of hard work, Marie named two new elements, radium and polonium. Both elements emit far more energy than uranium. Radium is one million times more active than uranium! Marie named this newfound form of energy radioactivity. Marie and Pierre shared the 1903 Nobel Prize for their study of radiation. Marie also won the 1911 Nobel Prize for her discovery of radium and polonium. Do You Know? A woman winning a Nobel Prize was unheard of in 1903. In fact, Pierre Curie alone was first offered the Nobel, but he refused to accept if he could not share the prize with Marie. Still, only Pierre was allowed to deliver the acceptance speech.