Little Bits of History

July 11

Posted in History by patriciahysell on July 11, 2017

1801: Jean-Louis Pons discovered his first comet. Pons was born in 1761 to a poor family and they were able to provide little in the way of formal education. In 1789 he got a job working as a caretaker at a Marseille observatory. He was able to gain some insights as he helped the astronomers with their observations. Eventually, he learned to use the equipment himself and had an ability to recall star fields and note changes in them. The more experienced astronomers sometimes poked fun at the young man’s naïveté and one of them, Franz Xaver von Zach, even told the student to look for comets when sunspots were visible. Although meant as cruel joke, it make have actually been very good advice.

On this day, Pons made his first comet discovery. Charles Messier is given joint credit for the comet’s discovery. Pons seemed to have used a telescope of his own design, one with a large aperture and short focal length. He called it “Grand Chercheur” or “Great Seeker”. While Pons was able to clearly remember star fields without as many notes, making him remarkably adept at finding changes in the skies, it meant his notes were not of the best quality and his observations are tantalizingly vague.

Telescopes are helpful for looking into the night sky. There are many different types of them, with the comet seeker one of those classified by the type of task they perform. Optical telescopes are refracting, reflecting, or catodioptric and each type has many specific subcategories. The task performing telescopes are also optical in nature. There are also telescopes working outside the optical spectrum such as infrared, ultraviolet, x-ray, and broad spectrum. Telescopes can also be classified by the type of mounting upon which they sit. First developed in the 1600s, they have been refined and helped to broaden the scope of astronomy, our understanding of the way the universe works, and the complexity and the vastness of space.

Pons became a noted astronomer and director at observatories. He was invited to teach astronomy at La Specola in Florence. He discovered five periodic comets, three of which still retain his name. One comet he found in 1818 was named by him as Comet Encke after the man who was able to calculate the comet’s orbit. Encke however, always called the comet Pons’s Comet. Pons received the French Academy of Science’s Lalande Prize in 1818 for discovering three comets in one year. He won it again in 1820 and again in 1827 after discovering many more comets. In total, he found 37 comets between 1801 and 1827, making him the greatest visual comet discoverer of all time. His eyesight failed him and he was forced to retire. The astronomers of the world honored him by naming a crater on the Moon after him.

For my confirmation, I didn’t get a watch and my first pair of long pants, like most Lutheran boys. I got a telescope. My mother thought it would make the best gift. – Wernher von Braun

We see past time in a telescope and present time in a microscope. Hence the apparent enormities of the present. – Victor Hugo

What you do is, you have your drawing board and a pencil in hand at the telescope. You look in and you make some markings on the paper and you look in again. – Clyde Tombaugh

The development of the telescope, together with increased knowledge of things, brought men to see that the earth is not what man had once thought it to be. – Joseph Franklin Rutherford


July 4

Posted in History by patriciahysell on July 4, 2017

1054: A “guest star” is first noticed in China. In Chinese astronomy, the term refers to a star which appears suddenly where no star had been before and then, after some time, disappears. These are novas or supernovas. In ancient times, context is needed to determine if the guest star is one of the catastrophic events or a comet with or without a tail. Extant Chinese records come from at least two sources. There are other worldwide references to what is now known as SN 1054 coming from questionable sources in European works and more substantial records of Ancestral Puebloan culture found in New Mexico, United States. The remnant of the explosion of the star once located in the sky near Zeta Tauri is called the Crab Nebula.

There are eight known supernovas in the Milky Way, identified because of existing testimony of the time. The old Chinese texts show the appearance of a guest star during the reign of Emperor Renzong of the Song dynasty. By studying the writings and correlating known historical events, it was found to be on this day. Writings of the event are included in both Song Shi and Song Huiyao, both texts about the history of the Song dynasty. They describe the sudden appearance of new star near Zeta Tauri which remained visible for a total of 642 days, with the star bright enough to be visible even during the daylight hours for 23 of those days.

The Crab Nebula (M1, Messier 1, NGC 1952, Taurus A, Sh2-244) was the first astronomical object identified with a historical supernova explosion. The Nebula is not visible to the naked eye but can be seen even with binoculars (under favorable conditions). The nebula was first identified in 1731 but to little fanfare. Charles Messier was studying a comet in 1758 and found the nebula again. Although officially cataloged, nothing else was known of it. With spectroscopy, the artifact was again found in 1913 and several photos taken years apart revealed the nebula was expanding. Discovering the relationship between SN 1054 and the Nebula began in 1921.

Edwin Hubble proposed a controversial idea – the nebula was the debris of the 1054 supernova. Knowing as much about astronomical events as we now do, it is currently thought the supernova actually took place in April or early May and was bright enough to finally be discovered in July. The Crab Pulsar was the cause for more study of the Crab Nebula. Because of early recordings, the date of the event and the data collected gave astronomers a greater understanding of the highly magnetized, rotating neutron star or white dwarf. While we know much about the nebula, we are still uncertain about several details. Watching the night sky still allows us to learn much about the universe in which we live.

Astronomy? Impossible to understand and madness to investigate. – Sophocles

Astronomy, as nothing else can do, teaches men humility. – Arthur C Clarke

The universe seems neither benign nor hostile, merely indifferent. – Carl Sagan

Astronomy’s much more fun when you’re not an astronomer. – Brian May

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Not So Special

Posted in History by patriciahysell on December 30, 2012
Edwin Hubble

Edwin Hubble

December 30, 1924: Edwin Hubble announces there are other galaxies in the universe. Copernicus stated the solar system was heliocentric, but not very loudly. Galileo backed him up with a louder voice and since that would dispute some Biblical scripture, he was forced to recant and punished for his heresy. Regardless of the Pope’s conviction, the solar system is heliocentric and the universe does not revolve around the Earth. Not only are we not the center of everything, we aren’t even a very important part of everything that is, except to ourselves, of course. Telescopes gave scientists better and better images of what was beyond naked eye vision out there in deep space.

Edwin Hubble was born in Missouri in 1889. The family moved to Chicago in 1898. Hubble was an athlete and while in high school, he broke the state record for the high jump. He went the University of Chicago and played basketball for them. He went on to win a Rhodes scholarship and at Oxford he studied law. He eventually earned a Ph.D. in astronomy, but he still practiced law in Kentucky for a time. He rose to rank of major while serving in the US Army during World War I. After the war, bored with law, he went back to astronomy and peering into the abyss of the night sky.

He worked with the new 100-inch telescope at Mount Wilson in Southern California and studied spiral nebulae. It was thought, at the time, that these fuzzy patches in the sky were clouds of gas or dust within our galaxy. The Milky Way was thought to contain everything in the universe (still believing we were the central focus of the entire universe in some small way) except the Magellanic Clouds. However, as Hubble studied the nebula Andromeda, he found a number of stars. Some of these were Cepheid variable stars which vary in intensity from bright to dim. Back in 1912, Henrietta Leavitt of Harvard had shown that by using these Cepheid stars, one could calculate the distance between Earth and their position.

On this date, Hubble announced that we were not the only galaxy and in fact there were many different galaxies out there. He was able to compute the distance to Andromeda as approximately 860,000 light years. The farthest stars of our own galaxy are about one-eighth of that distance. Although this was indeed a cosmic discovery, it was not front page news. Hubble went on to discover about 25 more galaxies during his life. He also employed the Doppler effect and during the 1920s was able to prove that stars were moving away from us. He also proved their red shift was proportional to the distance. Hubble died in 1953. NASA honored him by naming their space telescope after him.

The great spirals… apparently lie outside our stellar system.

The history of astronomy is a history of receding horizons.

Equipped with his five senses, man explores the universe around him and calls the adventure Science.

Past time is finite, future time is infinite. – all from Edwin Hubble

Also on this day:

Once in a Blue Moon – In 1982, the only total eclipse of a blue moon in the entire century took place.
Countess Bathory – In 1610, the Blood Countess was stopped.
Ted on the Loose – In 1977, Ted Bundy once again escaped from prison.