*Make use of time, let not advantage slip. – William Shakespeare*

## 1900 – Jan Oort, Dutch astronomer is born.

Jan Hendrik Oort ForMemRS was a Dutch astronomer who made significant contributions to the understanding of the Milky Way and who was a pioneer in the field of radio astronomy. His New York Times obituary called him “one of the century’s foremost explorers of the universe;” the European Space Agency website describes him as, “one of the greatest astronomers of the 20th century,” and states that he “revolutionised astronomy through his ground-breaking discoveries.” In 1955, Oort’s name appeared in Life Magazine’s list of the 100 most famous living people. He has been described as “putting the Netherlands in the forefront of postwar astronomy.”

Oort determined that the Milky Way rotates and overturned the idea that the sun is at its center; he discovered mysterious invisible ‘dark matter’ in 1932 which is believed to make up roughly 84.5% of the total matter in the universe and whose gravitational pull causes “the clustering of stars into galaxies and galaxies into connecting strings of galaxies.” He discovered the galactic halo, a group of stars orbiting the Milky Way but outside the main disk. Additionally Oort is responsible for a number of important insights about comets, including the realization that their orbits “implied there was a lot more solar system than the region occupied by the planets.”

The Oort cloud, the Oort constants, and the Asteroid, 1691 Oort, were all named after him.

## 1906 – Kurt Gödel, Czech-American mathematician is born.

Kurt Friedrich Gödel was an Austrian, and later American, logician, mathematician, and philosopher. Considered with Aristotle and Gottlob Frege to be one of the most significant logicians in history, Gödel made an immense impact upon scientific and philosophical thinking in the 20th century, a time when others such as Bertrand Russell, A. N. Whitehead, and David Hilbert were pioneering the use of logic and set theory to understand the foundations of mathematics.

Gödel published his two incompleteness theorems in 1931 when he was 25 years old, one year after finishing his doctorate at the University of Vienna. The first incompleteness theorem states that for any self-consistent recursive axiomatic system powerful enough to describe the arithmetic of the natural numbers (for example Peano arithmetic), there are true propositions about the naturals that cannot be proved from the axioms. To prove this theorem, Gödel developed a technique now known as Gödel numbering, which codes formal expressions as natural numbers.

He also showed that neither the axiom of choice nor the continuum hypothesis can be disproved from the accepted axioms of set theory, assuming these axioms are consistent. The former result opened the door for mathematicians to assume the axiom of choice in their proofs. He also made important contributions to proof theory by clarifying the connections between classical logic, intuitionistic logic, and modal logic.

## 2001 – Dennis Tito becomes the world’s first space tourist.

Dennis Anthony Tito is an American engineer and multimillionaire, most widely known as the first space tourist to fund his own trip into space. In mid-2001, he spent nearly eight days in orbit as a crew member of ISS EP-1, a visiting mission to the International Space Station. This mission was launched by the spacecraft Soyuz TM-32, and was landed by Soyuz TM-31.

## 2011- Adafruit adds images to invoices!

Adding images to invoices will make shipping easier, reduce mistakes and help customers identify what the heck it is that’s in that box. Since zen cart already has images for all items, its really easy to add… By default, it will use the thumbnails used in the shop navication. Optionally, you can make a folder in images/ called /invoice to override the images in case you’d like a different image on the invoice than shows up on the website.

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