APOD 3.2: The Antikythera Mechanism

I liked this particular "astronomy picture of the day" because of its incredible historical connection. the "Antikythera Mechanism" was found in an ancient Greek ship at the bottom of the sea, which most likely sank around 80 BC. Such a gear was not thought to have been created for another 1,000 years later- it was a sort of mechanical computer. The wheels and gears create a sort of orrery of the sky; although some of its functions are unknown, one use was probably to predict events such as eclipses. It is about the size of a large book.

• Moon (silver)
• Mercury (turquoise)
• Venus (lapis lazuli)
• Sun (gold)
• Mars (red onyx)
• Jupiter (white crystal)
• Saturn (obsidian).

APOD 3.1- Stickney Crater

The surreal-looking, enhanced-color picture, belonging to NASA, displays Stickney Crater, which is the largest crater on the martian moon Phobos. It was taken by the WiRISE camera aboard the Mars Reconnaissance Orbiter in 2008. The crater was named for the wife of the astronomer Asaph Hall, who was responsible for discovering both of Mars' moons.

Stickney Crater is half the diameter of Phobos; whatever created it likely could have destroyed the moon in fact. The streaks are probably from loose material sliding down the walls of the geological feature (although Phobos' gravity is less than 1/1000th Earth's gravity), and the bluish regions denote exposed surfaces. There are many groves in Stickney Crater, created during the impact that produced the feature.

APOD 2.8: "Jellyfish Nebula"

This usually faint, elusive nebula, which looks much more like a brain than a jellyfish to me, is part of a supernova remnant known as IC 443. It forms a debris cloud, from an enormous star that exploded. Light from the explosion reached Earth 30,000 years ago- although I should like to review how astronomers find this out. This nebula is located near a bright star called Eta Geminorum, in the constellation Gemini. It is about 5,000 light years away, and it is a "complex environment."

Nathaniel Bowditch Biography

Letts 1

Olivia Letts

Mr. Percival

Astronomy, Per. 3

10 Jan. 2013

Nathaniel Bowditch- Navigator and Mathematician

            In 1773, the year of the Boston Tea Party, Nathaniel Bowditch was born in Salem, Massachusetts.  Because his father, Habakkuk, was a shipmaster, he grew up exposed to the idiosyncrasies of seafaring ways in a community where daring mariners were esteemed and blows were delivered against British shipping during the time of the American Revolution.  It was Bowditch’s family’s brief stay in Danvers that shielded him from the dangers of the political and military turmoil that was occurring.  As a child he tried to fill every moment he could learning mathematics; although the school system at that time was poor, there he excelled.  His father was nearly always absent on voyages, and while Bowditch was adored by his mother for his promising future, the family was most often hungry and in a state of near-poverty.  Thus, Habakkuk Bowditch pulled his son out of school, and young Nathaniel became an apprentice clerk at a ship chandler’s shop.  However, he taught himself calculus, and also Latin and French, which allowed him to both read and translate many influential works.  He carried on with his studies all through 1795-1806, during which he undertook many sea voyages aboard merchant ships. As his mathematical, observational, and scientific skills were sharpened he also became a rising businessman and after his final voyage he became president of a prosperous fire and marine insurance company in Salem. 

While president, the mathematical and scientific research he undertook earned him great respect.  His first wife died in 1798 after only seven months of marriage, plunging him into a depression.  He was married again two years later to Mary Ingersoll, with whom he would have

Letts 2

many children.  The many honors he attained for his work also lent him comfort; he was elected to the American Academy of Arts and Sciences in 1799.  After his New American Practical Navigator was published in 1802, Harvard awarded him a Master of Arts Degree. He became known as the father of modern maritime navigation because of this detailed instructional work, which also improved upon John Moore’s faulty yet influential Practical Navigator.  Harvard would later offer him a chair of mathematics and physics, which he refused along with the U.S. Military Academy and the University of Virginia, though he would also go on to be elected to the American Philosophical Society, the Royal Irish Academy, and the Royal Society of Edinburgh, and the Royal Society of London.  Aside from naval charts, Bowditch wrote many astronomical articles based on his observations.  In 1806 he published a well-read article on the motion of the moon.  Using a magnetic needle in some interesting experiments, he illustrated and bolstered concepts of revolution, the Earth’s oblateness (slightly flattened at the poles), and he also corrected parts of the celestial table including meridians and latitudes.  Bowditch wrote publications on meteor showers, and the orbits of three comets, and reportedly demonstrated how to find the place of a meteor.  He added touches to many famous works, including Newton’s.

            Lissajous curves (part of complex parametric equation systems) became known as Bowditch curves due to the man’s groundbreaking mathematical studies on them conducted through the observation of the motion of a pendulum suspended on two points.  Bowditch also translated Pierre-Simon de Laplace’s Mécanique céleste in 1818, to which he added commentary.  He could not afford to have the various volumes published until 1829, 1832, 1834, and 1839, but these translations became vital to the development of theoretical astronomy and mathematics in the United States. He did not form any great theories but instead is admirable for his painstaking mathematical work and tireless observations.  He died in 1838 from stomach cancer, and is said to have thousands of descendents in the United States. 

APOD 2.7: Spiral Planetary Nebula

The mind-blowing picture of nebula NGC 5189, also known as the Spiral Planetary Nebula (and recently called the Christmas Ornament Nebula), was recently taken by the Hubble Heritage Team. To me, this nebula resembles an approaching celestial lion, stepping forward, his tail curled up and around.

NGC 5189 is a highly complex nebula observed by the Hubble Space Telescope; it is a dying star that is part of a binary star system with a slowly-moving symmetry axis. The nebula spans about three light years and is 3,000 light years away from Earth, near the southern Fly constellation. Previous research done on NGC 5189 showed that the nebula is descended from epochs of "material outflow," lik a bright torus running across.

APOD 2.6: Lunar Halo Over Spain x4

The beautiful image, photographed by Dani Caxete, depicts a beautiful moon near Madrid, Spain, whose appearance was crystallized into having a quadruple halo due to falling ice crystals. Such a view, with a 22 degree halo, is very rare. The 22 degree arc is elongated by "column ice crystals" then also further refracted through more distant ice crystals to give the semblance of a 46 degree, rainbow-like halo. The lovely scene, as though it had been taken from a Christmas storybook, is set also by the Sierra de Guadarrama mountain range. The winter night sky scape includes many of the classic winter constellations with such stars as Sirius in Canis Major, Orion's Belt stars, and Betelgeuse within the arcs.

When the arcs and halos around the moon occur, they can be visible anywhere between a few minutes to a few hours.

Nathaniel Bowditch- Bibliography Listings

Taylor, W. Leonard, M.D. "America's First Mathematician, Astronomer and Philosopher: Nathaniel Bowditch." Fortnightly Club of Redlands. N.p., 9 Mar. 2001. Web. 04 Dec. 2012. <http://www.redlandsfortnightly.org/papers/Taylor01.htm>.

Berry, Robert Elton. "The Life of Nathaniel Bowditch." The Scientific Monthly 56.3 (1943): 277-78. JSTOR. Web. 4 Dec. 2012.

O'Connor, J. J., and E. F. Robertson. "Nathaniel Bowditch." Bowditch Biography. N.p., July 2000. Web. 04 Dec. 2012. <http://www-history.mcs.st-andrews.ac.uk/Biographies/Bowditch.html>.

Bowditch, Harold. "Nathaniel Bowditch." The William and Mary Quarterly 3rd ser. 3.2 (1946): 306
07. JSTOR. Web. 4 Dec. 2012.