Friday, December 19, 2014

David Rittenhouse Essay


Amber Stich

Percival

D.E. Astronomy

19 December 2014

David Rittenhouse Essay
David Rittenhouse, First Director of the United States Mint
            David, the son of Matthias and Elizabeth Williams Rittenhouse, was born on a farm in 1732, about 20 miles north of Philadelphia in the town of Norriton. Of German Mennonite and Welsh Quaker decent, Rittenhouse belonged to the Presbyterian Church and was given informal education. Most of Rittenhouse’s education was self-taught. Rittenhouse married Eleanor Coulston in 1766 and had two daughters. When Eleanor died, Rittenhouse married Hannah Jacobs in 1772. Rittenhouse was of poor health, mostly due to his duodenal ulcer. But despite his ailments, Rittenhouse was a major contributor to both astronomy, and the early United States. Rittenhouse spent most of his life in Philadelphia.

            By trade, Rittenhouse was a clock and mathematical instrument maker. He was known for his workmanship. His astronomical clock used a pendulum he himself had designed. Many of Rittenhouse’s instruments were so well made they were able to be preserved to this day. His handmade instruments were far superior to any other in the United States at that time. Some of the instruments Rittenhouse made were surveyors’ compasses, levels, transits, telescopes, zenith sectors, thermometers, barometers, a hygrometer, and eyeglasses. Rittenhouse was one of the early users of spider webs over a telescope’s eyepiece to be used for cross hairs. He also built a collimating telescope in his observatory. The Vernier compasses Rittenhouse built were known in America as “Rittenhouse compasses”, and the stove type he made for Benjamin Franklin’s fireplace were deemed a “Rittenhouse stove”. Rittenhouse, among his experiments with pendulums, created the concept of magnetic dipoles. During his diffraction studies, Rittenhouse created plane transmission gratings, using fine wire across a frame and followed this by stating the law of governing their displacement.

Though it was often overlooked –David Rittenhouse played an important part in the development of Pennsylvania. Rittenhouse was the most celebrated American surveyor; marking Pennsylvania’s borders with its surrounding states. During the American Revolution, Rittenhouse helped design the Delaware River defenses and worked on the production of saltpeter and guns. Rittenhouse also experimented with telescope scopes for rifles and cannons. Along with this, Rittenhouse participated in the forming of the Pennsylvanian Constitution of 1776, the Board of War, and the vice-presidency of the Council of Safety. Occasionally, Rittenhouse held the responsibility of executive leadership of the state. From 1777-1798, Rittenhouse served as the treasurer of Pennsylvania. And when Thomas Jefferson was working on his report for weights and measured, he turned to Rittenhouse as a consultant and named him the first director of the U.S. Mint in 1792.

            Beginning in 1773, Rittenhouse moved his talents to astronomy. Rittenhouse began supplying almanacs in Pennsylvania, Maryland, and Virginia with astronomical calculations. Rittenhouse first success was in his observation of the transit of Venus in 1769. He then submitted the best American calculation contribution to the worldwide efforts to establish the sun’s parallax. On his publishing of his initial volume of Transactions, which is where he published most of his work, Rittenhouse was made the President of the American Philosophical Society, succeeding Ben Franklin. Rittenhouse built all of the instruments used by the Norriton observation group. To enable him to keep daily records and conduct regular observations for his publishing data and calculations on meteors, comets, Jupiter’s satellites, Mercury, Uranus and various eclipses- Rittenhouse established the Philadelphia observatory. Rittenhouse’s best published work was an original formula for finding the place of a planet in its orbit. Rittenhouse also figured out logarithm calculations as a study of the period of a pendulum. Rittenhouse may have independently developed a system of calculus during his research of the area. Rittenhouse also published various accounts of lightning, meteorology, geology, and aspects of natural history.

            Rittenhouse, a prominent American figure of his time, is often overlooked by historians. Rittenhouse was the power-house of behind-the-scenes work, overshadowed, but not underappreciated, by public figures. He contributed major advancements in mathematical and astronomical instruments, which he used himself to contribute valuable data to the scientific community. Rittenhouse’s poor health was the cause of his death; he died on June 26th, 1796 of cholera. His legacy was of being one of American’s “untutored geniuses”.

Monday, December 15, 2014

APOD 2.6

See Explanation.  Clicking on the picture will download
 the highest resolution version available.
One celestial body that never fails to amaze is the Nebula. The nebula pictured above is the Flame Nebula- about 1,500 light years away. The Nebula is located near the Orion constellation. The glow and dark dust lanes gives the nebula the fire-like appearance. The bright star Alnitak, of the Belt of Orion, shines the energetic light on the nebula. Alnitak does this by knocking electrons away from the hydrogen gas clouds that reside in the nebula -the electrons and ionized hydrogen then recombine. The Flame Nebula (NGC 2024) picture is a mixed composite of both visible and infrared light. The Flame Nebula is part of the Orion Molecular Cloud Complex, a star-forming region that also houses the Horsehead Nebula.

Observation Post (12/15/14)

After watching the Gemini meteor shower a few nights ago, I gained a new appreciation for what I'm learning in astronomy. Things are happening in space that I never knew about before- and now I get to go outside and not only watch them happen- but understand what's happening and why. I have always liked stargazing, but actually being able to identify constellations and stars gives the practice a whole new light. One of my favorite things to do is to stargaze with my boyfriend and compete to see who can find the most satellites in one night. I never before had this appreciation for doing something so simple as just looking up.

Monday, December 8, 2014

D. Rittenhouse (Sources)

David Rittenhouse Biography Sources

Science and Its Times:
"David Rittenhouse." Science and Its Times. Ed. Neil Schlager and Josh Lauer. Vol. 4: 1700 to 1799. Detroit: Gale, 2000. 367. Gale Virtual Reference Library. Web. 8 Dec. 2014.

The Complete Dictionary of Scientific Biography:
"Rittenhouse, David." Complete Dictionary of Scientific Biography. Vol. 11. Detroit: Charles Scribner's Sons, 2008. 471-473. Gale Virtual Reference Library. Web. 8 Dec. 2014.

Encyclopedia of World Biography:
"David Rittenhouse." Encyclopedia of World Biography. 2nd ed. Vol. 13. Detroit: Gale, 2004. 180-181. Gale Virtual Reference Library. Web. 8 Dec. 2014.

Friday, December 5, 2014

APOD 2.5

See Explanation.  Clicking on the picture will download
 the highest resolution version available.
 
This pillar of dust makes what looks like to be a 20 light year long seahorse. The dust structure art is provided to courtesy of our neighboring Large Magellanic Cloud. The Large Magellanic Cloud is inside a star forming region near the Tarantula Nebula. The nebula is in the midst of forming a star cluster is referred to as NGC 2074. The center is visible in this image if you look towards the top around where the neck of the seahorse is. This image was taken back in 2008 by the Hubble Space Telescope using its Wide Field Planetary Camera 2 to celebrate Hubble's 100,000th trip around Earth. As these stars form in the cluster, their light and wind will erode the dust structure away over the next million years or so.

Wednesday, December 3, 2014

Observation (12.3)

In all honesty -astronomy is starting to impact my life. The other day while the sky was clear I was too busy identifying constellations such as Ursa Minor to notice the car heading for me. Also, I had to explain to my coach why I was late for a 5 am practice because I was too busy trying to find zodiacal constellations across the ecliptic. This morning was beautifully clear, but as much as I wanted to stop and stare -I knew I coach wouldn't buy my excuse again.