Milky Way Galaxy

The Milky Way Galaxy, commonly referred to as just the Milky Way, or sometimes simply as the Galaxy, is the galaxy in which the Solar system is located. The Milky Way is a barred spiral galaxy that is part of the Local Group of galaxies. It is one of billions of galaxies in the observable universe. Its name is a translation of the Latin Via Lactea, in turn translated from the Greek, Galaxias, referring to the pale band of light formed by stars in the galactic plane as seen from Earth.

Some sources hold that, strictly speaking, the term Milky Way should refer exclusively to the band of light that the galaxy forms in the night sky, while the galaxy should receive the full name Milky Way Galaxy, or alternatively the Galaxy. However, it is unclear how widespread this convention is, and the term Milky Way is routinely used in either context.

The stellar disk of the Milky Way Galaxy is approximately 100,000 light-years (30 kiloparsecs, 9×10¹⁷ km) in diameter, and is considered to be, on average, about 1,000 ly (0.3 kpc) thick. It is estimated to contain at least 200 billion stars and possibly up to 400 billion stars, the exact figure depending on the number of very low-mass stars, which is highly uncertain. This can be compared to the one trillion (10¹²) stars of the neighboring Andromeda Galaxy. The stellar disc does not have a sharp edge, a radius beyond which there are no stars. Rather, the number of stars drops smoothly with distance from the centre of the Galaxy. Beyond a radius of roughly 40,000 ly (12 kpc) the number of stars drops much faster with radius, for reasons that are not understood.

The galaxy consists of a bar-shaped core region surrounded by a disk of gas,dust and stars forming four distinct arm structures spiralling outward in a logarithmic spiral shape. The mass distribution within the galaxy closely resembles the Sbc Hubble classification, which is a spiral galaxy with relatively loosely wound arms. Astronomers first began to suspect that the Milky Way is a barred spiral galaxy, rather than an ordinary spiral galaxy, in the 1990s.Their suspicions were confirmed by the Spitzer Space Telescope observations in 2005 which showed the galaxy's central bar to be larger than previously suspected.

Quasars

A quasi-stellar radio source ("quasar") is a very energetic and distant galaxy with an active galactic nucleus. They are the most luminous objects in the universe. Quasars were first identified as being high redshift sources of electromagnetic energy, including radio waves and visible light, that were point-like, similar to stars, rather than extended sources similar to galaxies.

While there was initially some controversy over the nature of these objects—as recently as the early 1980s, there was no clear consensus as to their nature—there is now a scientific consensus that a quasar is a compact region in the center of a massive galaxy surrounding its central super massive black hole. Its size is 10–10,000 times the Schwarzchild radius of the black hole. The quasar is powered by an accretion disc around the black hole.

Famous Women

Early civilization

Merit Ptah

was an early physician in ancient Egypt. She is most notable for being the first woman known by name in the history of the field of medicine, and possibly the first named woman in all of science as well. Her picture can be seen on a tomb in the necropolis near the step pyramid of Saqqara. Her son, who was a High Priest, described her as "the Chief Physician."

Merit Ptah

Aglaonike

also known as Aganice of Thessaly is cited as the first female astronomer in ancient Greece. She is mentioned in the writings of Plutarch and Apollonuis of Rhodes as the daughter of Hegetor of Thesally. She was regarded as a sorceress for her ability to make the moon disappear from the sky, which has been taken to mean she could predict the time and general area where a lunar eclipse would occur.

Aglaonike

Theano

was a Pythagorean philosopher. She was said by many to have been the wife of Pythagoras although others made her the wife of Brontinus. A few fragments and letters ascribed to her have survived which are of uncertain authorship. She is believed by some historians to have been a student of Pythagoras and later a teacher in the Pythagorean school, which had 28 female Pythagoreans participating in it

THEANO

Maria the Jewess

or Maria Prophetissima, Maria Prophetissa, Mary Prophetissa, Miriam the Prophetess is estimated to have lived anywhere between the first and third centuries A.D. She is attributed with the invention of several chemical apparatus, is considered to be the first non fictitious alchemist in the Western world, an early pioneer in chemistry (or alchemy), and one of the most famed women in science ever.

Maria Prophetissa

Hypatia

born between AD 350 and 370; died March 415 was a Greek scholar from Alexandria, Egypt. Considered the first notable woman in mathematics who also taught philosophy and astronomy.

Hypatia as imagined by Raphael

Scientific Revolution

Margaret Cavendish

Observations upon Experimental Philosophy and Grounds of Natural Philosophy.

Margaret Cavendish

Maria Winkelmann

A German astronomer, Maria was taught by her father and uncle, who believed that she deserved the equivalent education bestowed upon boys. Her interest in astronomy was nurtured and she studied with self-taught astronomer and farmer Christopher Arnold, for whom she eventually worked. Through Arnold, Maria developed a relationship with renowned astronomer and mathematician Gottfried Kirch. Despite being 30 years her senior, they married and raised four children who all grew up to study astronomy with their parents.

maria winkelmann

Industrial Revolution

Gabrielle Émilie Le Tonnelier de Breteuil, marquise du Châtelet

(17 December 1706, Paris – 10 September 1749, Luneville) was a French mathematician, physician and author during the Age of Enlightenment. Her crowning achievement is considered to be her translation and commentary on Isaac Newton's work Principia Mathematica published in 1759, ten years after her death, hers is still the standard translation in French.

Émilie du Châtelet

Marie-Anne Pierette Paulze

was a French chemist. She is most commonly known as the spouse of Antoine Lavoisier (Madame Lavoisier) but many do not know of her accomplishments in the field of chemistry: she acted as the laboratory assistant of her spouse and contributed to his work.

Caroline Lucretia Herschel

(16 March 1750 – 9 January 1848) was a British astronomer the sister of astronomer Sir Friedrich Wilhelm Herschel with whom she worked throughout both of their careers. Her most significant contribution to astronomy was the discovery of several comets and in particular the periodic comet 35P/Herschel-Rigollet, which bears her name. At the age of ten, Caroline was struck with Typhus, a bacterial disease spread by lice or fleas. This disease stunted Caroline’s growth and she never grew past four foot three. Due to this deformation, her family assumed that she would never marry and that it was best for her to remain a house servant, which her mother trained her to do until her father’s passing. Her father, Isaac believed that she was not pretty enough to ever marry and that was true, however she accomplished much more in life than marriage and bearing children.

Caroline Herschel

19th century

Mary Fairfax Somerville

(26 December 1780 – 28 November 1872) was a Scottish science writer and polymath, at a time when women's participation in science was discouraged. She studied mathematics and astronomy, and was the second woman scientist to receive recognition in the United Kingdom after Caroline Herschel.

Mary Somerville

Augusta Ada King, Countess of Lovelace

(10 December 1815 – 27 November 1852), bornAugusta Ada Byron, was an English writer chiefly known for her work on Charles Babbage's early mechanical general-purpose computer, the analytical engine. Her notes on the engine include what is recognised as the first algorithm intended to be processed by a machine; as such she is regarded as the world's first computer programmer.

Ada Lovelace

Catherine Elizabeth Benson

was the first woman to earn a college bachelor's degree.

Cecilia Payne-Gaposchkin

(May 10, 1900 – December 7, 1979) was an English-American astronomer who in 1925 was first to show that the Sun is mainly composed of hydrogen contradicting accepted wisdom at the time.

Payne then studied stars of high luminosity in order to understand the structure of the Milky way. Later, with her husband, she surveyed all the stars brighter than the tenth magnitude. She then studied variable stars, making over 1,250,000 observations with her assistants. This work later was extended to the Magellanic Clouds, adding a further 2,000,000 observations of variable stars. This data was used to determine the paths of stellar evolution.

Cecilia Payne-Gaposchkin: Astronomer and Astrophysicist

Progress in Geology

Geology- is the study of the solid Earth and the processes by which it is shaped and changed. Geology provides primary evidence for plate tectonics, the history of life and evolution and past climates. In modern times, geology is commercially important for mineral and hydrocarbon exploration, is publically important for predicting and understanding natural hazards plays an essential role in geotechnical engineering and is a major academic disipline.

Contributors

Jean Andre Deluc and Horace Benedict de Saussure

first to use the word geology from Greek word Geo meaning Earth and logos meaning speech.

Alfred Wegener

continental drift(is the movement of the Earth's continent relative to each other. It was not until the development of the theory of plate tectonics in the 1960s, that a sufficient geological explanation of that movement was found.)

Pangea Continent Map -

Continental Drift

Robert S. Dietz and Harry s. Hess

Seafloor spreading occurs at mid-ocean ridges where new oceanic crust is formed through volcanic activity and then gradually moves away from the ridge. Seafloor spreading helps explain continental drift in the theory of plate tectonics.

Seafloor spreading (This is how the Mariana's Trench was formed)

SK Runcorn

concept of paleomagnetism(is the study of the record of the Earth's magnetic field in rocks. Certain minerals in rocks can record direction and intensity of the field as it has changed over geologic time. This provides information on the geodynamo and the fluid dynamics of the outer core of the Earth. The record of these changes in rocks and sediments provides a time scale that is used in geochronology).

Pacific Northwest

Paleomagnetic Laboratory at WWU:

Gene Shoemaker

gave the study of the moon to the Lunar geologist.