Monthly Archives: April 2018

It takes a lot of black dye to make solid black crystals. — Black crystals can look translucent, like black diamonds or smoky quartz, or opaque, like anthracite. You can take most crystal recipes and use them to grow black crystals. The Secret to Black Crystals While it’s easy to grow crystals in rainbow colors, black is a little trickier because a lot […]

How to Grow Black Crystals

This entry was posted on April 19, 2018 by Anne Helmenstine (updated on March 28, 2020)

Glenn Seaborg — April 19 is Glenn T. Seaborg’s birthday. Seaborg was an American chemist who discovered ten of the transuranium elements and over 100 different isotopes. Seaborg also proposed the actinide group arrangement for the periodic table. These elements were plutonium, americium, curium, berkelium, californium, einsteinium, fermium, mendelevium, nobelium and element 106. Element […]

Today in Science History – April 19 – Glenn T. ...

This entry was posted on April 17, 2018 by Todd Helmenstine (updated on May 11, 2021)

Albert Einstein — April 18 marks the passing of one of the most influential scientists of the 20th Century, Albert Einstein. Einstein started his career as a technical assistant at a Swiss Patent office in 1901. While working there, he obtained his Doctorate and published four papers on the photoelectric effect, Brownian motion, […]

Today in Science History – April 18 – Albert Einstein

This entry was posted on April 16, 2018 by Todd Helmenstine (updated on September 3, 2023)

Giovanni Battista Riccioli — April 17 is Giovanni Battista Riccioli’s birthday. Riccioli was an Italian astronomer and Jesuit priest who is best known for naming the features of the Moon. In 1651, he published Almagestum Novum which became a standard text for any serious astronomer well into the 19th Century. It was a collection […]

Today in Science History – April 17 – Giovanni Battista ...

This entry was posted on April 16, 2018 by Todd Helmenstine (updated on May 10, 2021)

Hans Sloane — April 16 is Hans Sloane’s birthday. Sloane was an Irish physician whose greatest contribution to science actually occurred after his death. During his lifetime, he was an avid collector of interesting items pertaining natural history. He amassed a large collection of books, notes, drawings, samples of plants and animals, and […]

Today in Science History – April 16 – Hans Sloane

This entry was posted on April 15, 2018 by Todd Helmenstine (updated on May 10, 2021)

Leonardo da Vinci — April 15 is the birthday of the original “Renaissance Man”, Leonardo da Vinci. He was an artist, musician, scientist, engineer, inventor, anatomist, and writer. As an artist, he is best known for his paintings. He painted the most famous portrait in history, the Mona Lisa. He painted one of the […]

Today in Science History – April 15 – Leonardo da ...

This entry was posted on April 14, 2018 by Todd Helmenstine (updated on October 16, 2021)

Christiaan Huygens — April 14 is Christiaan Huygens’ birthday. Huygens was a Dutch physicist, astronomer, and leading figure of the scientific revolution. Huygens is famous for the invention of the pendulum clock. Pendulums swing in a simple circular path where the time it takes to complete a single oscillation is proportional to the amplitude of […]

Today in Science History – April 14 – Christiaan Huygens

This entry was posted on April 13, 2018 by Todd Helmenstine (updated on May 10, 2021)

You shouldn't store open cans in the fridge because metals and BPA can leach into food. (maerzbow) — When you don’t finish an open can, you may be tempted to put some plastic wrap over it and put it in the refrigerator for later. However, it’s not a good idea to store open cans in the fridge. No, it won’t grow Salmonella or give you botulism. The risks […]

Why You Shouldn’t Store Open Cans in the Fridge

This entry was posted on April 13, 2018 by Anne Helmenstine (updated on January 14, 2023)

Annie Jump Cannon — April 13 marks the passing of Annie Jump Cannon. Cannon was an American astronomer who developed the star classification system in use today. Astronomy students learn the system using the mnemonic “Oh! Be A Fine Girl — Kiss Me!” The system ranks stars by their temperature, color and spectrum lines […]

Today in Science History – April 13 – Annie Jump ...

This entry was posted on April 12, 2018 by Todd Helmenstine (updated on May 10, 2021)