Last fall, we let you know that Caltech and The Feynman Lectures Website joined forces to create an online edition of The Feynman Lectures on Physics. They started with Volume 1. And now they’ve followed up with Volume 2 and Volume 3, making the collection complete.
All three volumes of The Feynman Lectures on Physics are now available for FREE online! (You’re welcome.)
Never thought astronomy could be so cute.
Great women of science
Rosalind Franklin (1920-1958) - British biophysicist and X-ray crystallographer who made critical contributions to the understanding of the fine molecular structures of DNA, RNA, viruses, coal, and graphite.
Marie Skłodowska-Curie (1867-1934) - Polish and naturalized-French physicist and chemist, famous for her pioneering research on radioactivity.
Chien-Shiung Wu (1912-1997) - Chinese American physicist with expertise in the techniques of experimental physics and radioactivity.
Émilie du Châtelet (1706-1749) - French mathematician, physicist, and author during the Age of Enlightenment.
Mae Jemison (1956) - American physician and NASA astronaut. She became the first African American woman to travel in space when she went into orbit aboard the Space Shuttle Endeavour on September 12, 1992.
Vera Rubin (1928) - American astronomer who pioneered work on galaxy rotation rates. She is famous for uncovering the discrepancy between the predicted angular motion of galaxies and the observed motion, by studying galactic rotation curves.
Ada Lovelace (1815-1852) - English mathematician and writer chiefly known for her work on Charles Babbage’s early mechanical general-purpose computer, the Analytical Engine. Her notes on the engine include what is recognised as the first algorithm intended to be processed by a machine. Because of this, she is often described as the world’s first computer programmer.
Kepler’s law of areas.
The law states that a line connecting a planet to a star will sweep out equal areas in equal times.
This can be seen in the above gif, where the area of the purple region is the same throughout.
When the planet is closer to the star, it moves faster, making the area wider. Where-as when the planet is further away from the star, it moves slower due to the area being longer, and not needing to be as wide.
Lightning Appreciation Post:
- There are nearly 500 lightning strikes every second around the world.
- Only about 100 of these strike the earth, the others are between and within the clouds themselves.
- Lightning is very visible from space (last gif from Astronaut Reid Wiseman)
- Besides regular storms (thunder storms, hurricanes, etc.) lightning can be found in volcanoes (gif 3) and even intense forest fires.
In conclusion: nature is fucking awesome!