In 1913 – Dr William David Coolidge received his patent for improvements in tungsten and methods for making filaments in incandescent lights. It made light bulbs last a lot longer. Too bad that in 1928, GE got a court to declare the patent was not an invention.
In 1924 – Astronomer Edwin Hubble announced that he had found stars in the spiral nebula Andromeda, and using Leavitt’s formula measured them as 860,000 light years away proving Andromeda was a separate galaxy. He would go on to find a dozen more galaxies.
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