Astronomer Biography: Jean Picard

Jean Picard was a notable French astronomer who made several noteworthy contributions to Modern Astrology. Picard was born in on the 21st of July in 1620 in La Fleche, a town in France. He died on July 12th of 1682 in Paris. It is safe to say he was probably French. Not much is known about his early childhood, but rumor has it that his father was a book seller and a local merchant. Jean began his formal education at the Jesuit College in La Fleche around 1636, which was probably one of the best educations a young man could receive at the time, the college being run by the Jesuits and all. It is further noted that graduated from the University of Paris in 1650 with an MA in astronomy. Interestingly enough, he also became a Catholic Priest, ordained in 1650. I'm not sure how he graduated from college and was ordained as a priest in the same year, but these are the cited facts. Later in 1666 (a very holy year, I'm sure) he founded the French Royal Academy of Sciences in Paris. It is disputed whether he was actually a founding member, but regardless he was inducted into the leading ranks in 1667 and provided a pension by the Academy, so it is more than likely he was involved in the founding. He also had a crater on the Moon named after him.

Picard is considered the founder of modern astronomy in France. His big claim to fame is being the first astronomer (or anyone for that matter) to use of Tycho Brahe's Quadrant to correctly measure the length of a degree on one of the Earth's Meridians. After successfully measuring a single degree via use of said Quadrant, Picard was then able to establish a Telescopic Positioning Measuring System. He did this using Brahe's Quadrant after attaching a telescopic lens which would be inclined (and rotated) by very small amounts at a time. The Quadrant was so finely graduated, he could observe angles down to the quarter of a minute (not the time minute). He was therefore able to use the stars as a frame of reference given a certain time (which he based off his contemporary Dutch physicist Christiaan Huygens' new pendulum clock). This method became the standard for measuring 'right ascension'. He also was able to use this mapping system to figure out how to supply Versailles with water, since he was able to map it's location in comparison to nearby water sources. On a different note, during his observations he discovered the 4th Trapezium star in M object 42.

Unlike many scientists of his time, Picard had a knack for collaborating with his contemporaries. He worked with both Issac Newton, Tycho Brahe, and even Giovanni Cassini, who most considered his arch-rival. His work with Newton is largely unnoticed, and is very important. His measurements of Earth's size through the measurement of the Meridians was able to be used in Newton's calculations to determine whether his law of Gravity was correct. He also had more collaboration with Brahe then just using his Quadrant, he also visited Brahe at his observatory in Sweden to measure his exact location on Earth so that Brahe's observances might be able to be correctly applied to other Astronomers in Europe.