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Hans Bethe-Physicist

“We need science education to produce scientists, but we need it equally to create literacy in the public. Man has a fundamental urge to comprehend the world about him, and science gives today the only world picture which we can consider as valid. It gives an understanding of the inside of the atom and of the whole universe, or the peculiar properties of the chemical substances and of the manner in which genes duplicate in biology. An educated layman can, of course, not contribute to science, but can enjoy and participate in many scientific discoveries which as constantly made. Such participation was quite common in the 19th century, but has unhappily declined. Literacy in science will enrich a person’s life.”
― Hans Bethe

Hans Albrecht Bethe

Hans Albrecht Bethe

 

Hans Bethe with Boyce McDaniel in the tunnel of the Cornell Electron Storage Ring, 1968. ©Russ Hamilton/CU

Hans Bethe with Boyce McDaniel in the tunnel of the Cornell Electron Storage Ring, 1968. ©Russ Hamilton/CU

Women in Science – Cecilia Helena Payne-Gaposchkin (1900-1979) Astronomer

She studied at Cambridge as an undergraduate but was not awarded a degree because the university didn’t grant degrees to women at that time. After meeting Harlow Shapley, the Director of the Harvard College Observatory, who had just begun began a graduate program in astronomy, she left England for the United States in 1923.

Payne-Gaposchkin became the first person to earn a Ph.D. in astronomy from Radcliffe (now part of Harvard). By studying the spectra of stars, Payne-Gaposchkin determined that hydrogen and helium were the most abundant elements in stars. She was the first woman to receive the rand of full professor at Harvard and also the first woman chairperson of a department at Harvard University.

Gaposchkin

Hither and Yon

“Let’s grant that the stars are scattered through space, hither and yon. But how hither, and how yon? To the unaided eye the brightest stars are more than a hundred times brighter than the dimmest. So the dim ones are obviously a hundred times farther away from Earth, aren’t they?

Nope.

That simple argument boldly assumes that all stars are intrinsically equally luminous, automatically making the near ones brighter than the far ones. Stars, however, come in a staggering range of luminosities, spanning ten orders of magnitude ten powers of ten. So the brightest stars are not necessarily the ones closest to Earth. In fact, most of the stars you see in the night sky are of the highly luminous variety, and they lie extraordinarily far away.

If most of the stars we see are highly luminous, then surely those stars are common throughout the galaxy.
Nope again.

High-luminosity stars are the rarest. In any given volume of space, they’re outnumbered by the low-luminosity stars a thousand to one. It’s the prodigious energy output of high-luminosity stars that enables you to see them across such large volumes of space.” 
― Neil deGrasse TysonDeath by Black Hole: And Other Cosmic Quandaries