Notices tagged with otd

"The moment of discovery" does not always exist: the scientist's work is too tenuous, too divided, for the certainty of success to crackle out suddenly in the midst of his laborious toil like a stroke of lightening, dazzling him by its fire.

Marie Curie was born #OTD in 1867.

#physics #WomenInSTEM

#OTD in 1675.

Leibniz makes the first use of the long s (∫) as a symbol of the integral in calculus. He adapted the integral symbol, ∫, from the letter ſ (long s), standing for summa (written as ſumma; Latin for "sum" or "total").

https://www.gutenberg.org/ebooks/author/7168

#books #mathematics

Italian physicist and academic, first woman to have doctorate in science Laura Bassi was born #OTD in 1711. Bassi became the most important populariser of Newtonian mechanics in Italy.

https://en.wikipedia.org/wiki/Laura_Bassi

#science #physics #WomenInSTEM

Lise Meitner died #OTD in 1968.

She is known for her part in the discovery of nuclear fission. Among physicists she had been known for many years as one of the early pioneers in the study of radioactivity. Einstein nicknamed her ‘the German Madame Curie’ despite being Austrian.

#physics #science

Subrahmanyan Chandrasekhar was born #OTD in 1910. He established an upper limit on the mass of stable white dwarf stars, and made numerous contributions to astrophysics and relativity.

Above the Chandrasekhar Limit – about 1.44 solar masses – electron degeneracy pressure cannot prevent a stellar remnant’s gravitational collapse into a neutron star or black hole.

Photo: Stephen Lewellyn / AIP

If you are a nerd of a certain age and want to fail your save vs feeling very old, the Dungeons & Dragons animated series debuted #OTD 41 years ago.

Physicist Carl Anderson was born #OTD in 1905.

Anderson developed an improved cloud chamber that he used to identify the positron – the antiparticle of the electron first theorized by Dirac.

Nowadays we use these particles for positron emission tomography (PET), android brains, and ghost busting.

Physicist Ernest Rutherford was born in Brightwater, New Zealand #OTD in 1871.

He discovered the nucleus, proton, and α and β particles; explained nuclear decay; and was the first person to successfully transmute one element into another.

Image: George Grantham Bain Collection, LOC

Astronomer Milton Humason was born #OTD in 1891.

He dropped out of the *eighth grade* and had little formal education, but a knack for difficult observations helped him collect much of the data used to establish what we now call Hubble’s Law.

Image: Emilio Segrè Archives

This #OTD thread contains my favorite newspaper headline of all time.
https://mastodon.social/@mcnees/110882817597054183

Astronomer Helen Sawyer Hogg was born #OTD in 1905. She was an authority on variable stars and globular clusters, and a pioneer of communicating science to the public.

Image: University of Toronto, Department of Astronomy and Astrophysics

Chemist Stephanie Kwolek was born #OTD in 1923.

She invented Kevlar, used in high-strength / low-weight applications like body armor and airplane parts. She also invented the Nylon Rope Trick demo!

Images: DuPont/Stephanie Kwolek

Humans first set foot on the Moon #OTD in 1969.

Aerodynamics engineer and mathematician Irmgard Flügge-Lotz was born #OTD in 1903.

She advanced the understanding of aerodynamic pressure on wings and turbine blades, pioneered the theory of discontinuous control systems, and was the first woman named full professor of engineering at Stanford.

Medical physicist and radiologist Edith Quimby was born #OTD in 1891.

One of the founders of nuclear medicine, she developed diagnostic applications for X-rays and radioisotopes. Her research on the penetrating power of radiation established safe levels for its use in treatments.

#OTD in 1609, Galileo Galilei aimed his telescope at the Moon.

While not being the first person to observe the Moon through a telescope (English mathematician Thomas Harriot had done it four months before but only saw a "strange spottednesse"), Galileo was the first to deduce the cause of the uneven waning as light occlusion from lunar mountains and craters. In his study, he also made topographical charts, estimating the heights of the mountains. via @wikipedia

#science #astronomy

Friends, here is a fun little physics story about satellites and relativity. It’s a day late for an #OTD, but please indulge me.

The Navigation Technology Satellite 2 (NTS-2) was launched into orbit on June 23, 1977, an early step in establishing the GPS NAVSTAR network. It was the first satellite to carry a Cesium atomic clock into orbit! 🧵

Image: Institute of Navigation

Sally Ride became the first US woman in space #OTD in 1983.

She was one of three mission specialists aboard the Space Shuttle Challenger for STS-7. At age 32 she was also the youngest US astronaut.

Image: NASA

A day late for an #OTD boost, but it’s always fun to look through a thread of Ralph McQuarrie concept art!
https://mastodon.social/@mcnees/110537520573170629

Mathematician Bernhard Riemann gave his famous lecture "On the Hypotheses Which Lie at the Foundations of Geometry" #OTD in 1854.

Riemann expanded on ideas introduced by his mentor Gauss and introduced what we now call Riemannian geometry.

Image: Familienarchiv Thomas Schilling