APOD 4.1

This picture depicts a swirling pool of hot gas around what is estimated to be a black hole in the center of this massive beast. We had just recently covered the topic of black holes and their predecessor: the neutron star. A neutron star is formed when the electron-degeneracy pressure is overcome by the force of gravity which occurs on the quantum level. This particular object, labeled GRO J1655-40 displays a flickering at a rate of 450 times per second which is caused by accretion discs surrounding the centered black hole.

George Willis Ritchey Bio

George Willis Ritchey was born in December 31, 1864 in Tupper’s Plains, Ohio. He was the son of an amateur astronomer and instrument maker. George’s father fled Ireland during the potato famine of the 19^th century. The family then settled in Cincinnati where George had continued his studies by attending the Cincinnati University. After completing his formal education in 1887, he became an instructor at the Chicago Manual Training School until 1896. The work he was doing reflected skills that a man by the name of George Ellery Hale found very impressive. If fact he was so impressed that he had asked Ritchey to take the role of chief optician at the Yerkes Observatory where he was able to utilize a 40-inch refractor telescope for photography of the heavens. Hale later offered him to work at another observatory, Mt. Wilson (over 5700 feet above sea level), but between his works at these two locations, in 1904, he had been elected an associated of the Royal Astronomical Society. His work at Mt. Wilson consisted of acting as head of instrument construction. Here he had begun construction of a 60-inch mirror telescope – the biggest mirror telescope at the time. After the construction of the 60-inch mirror, he had begun constructing yet an even bigger mirror, measuring 100-inches across, for the Hooper telescope. He also began work on his invention of cellular mirrors, which is widely known for. In 1910, Ritchey collaborated with a French optician by the name of Henry Chretien to construct the now widely used Ritchey-Chretien optic system, often abbreviated RC. This design however put Mr. Ritchey and Mr. Hale into conflict at the observatory on Mt. Wilson. Ritchey believed that a prototype of the system should be built but Hale argued that it was too tedious of a task and that there was no time to do that. This conflict led Hale into firing Ritchey just after he had completed the construction of the 100-inch reflector telescope. Filling Ritchey with sadness and depression, he settled in a private laboratory in the state of California continuing his work on cellular mirrors. Ritchey was later invited to discuss his recent innovations at the national Observatory in Paris, made a knight of the Legion of Honor, and became director of photo-telescopic research at the U.S. Naval Observatory. At the observatory he had designed and constructed a 40-inch RC reflector telescope. After this he retired to Azusa, California where he passed on the 4^th of November, in 1945. Before his death however, an event occurred on April 24^th, 1990 – the launch of the Hubble Space telescope which had contained the RC optic system. Although, it did carry some mirror measurement errors, the RC system made the operation possible. The two men who designed the system are remembered for their introduction of a new telescope which has altered our understanding of the heavens.

Sources

"Ritchey, George Willis." Complete Dictionary of Scientific Biography. Vol. 11. Detroit:

Charles Scribner's Sons, 2008. 470. Gale Virtual Reference Library. Web. 6 Mar. 2014.

Hughes, Stefan. "The Visionary." Astrophotography and Its Historyy Website, an EBook or Printed 

     Book for Those Interested in Astrophotography, Astronomy, Photography and Science. 

     'CATCHER' The History of Astrophotography Blog, 23 July 2012. Web. 06 Mar. 2014.

"George Willis Ritchey." Infoplease. Pearson Education, n.d. Web. 06 Mar. 2014. 

     <http://www.infoplease.com/encyclopedia/people/ritchey-george-willis.html>.