Isaac Newton was important for astronomy because he introduced the concept of gravity and how planets orbits around the sun. He developed three laws for motion and a law for gravitation. His findings changed the operations and understanding of the universe.
The ending of the Thirty Years’ War and the second Anglo-Dutch war starting in 1665 and ending in 1667 between the United Provinces and England.
William Penn: Oct 14, 1644 – Jul 30, 1718. William Penn was a refuge Quaker who was the founder of Pennsylvania. Born in London, he fled to North America for free worship after his disapproval of his Quaker beliefs.
Learning about major events and figures during this time period illustrates the amount of change going on between North America and Europe and how different the relationship between them was versus how it is today. The mind blowing discoveries have become general knowledge to everyone in the world today. Also, the lack of religious freedom has shown how far the world has come. It is important to remember the past because without these important figures, we would not be as advanced as we are today.
Galileo (1564-1642) was important to astronomy for many reasons. Galileo invented one of the first versions of a telescope, based on a spyglass, that he used to view the sky. His first major discovery was that the moon isn’t smooth, it has mountains, craters, and features on its surface. He then discovered many interesting things, like Jupiter’s moons, sunspots, and most importantly, the solar system orbits the sun, not the Earth.
Some key historical events that occurred during Galileo’s life:
1600 – The British East India Company is founded. This would eventually grow to be the largest and most powerful corporation in history.
1620 – The pilgrims arrive in current-day Massachusetts on the Mayflower, some of the first settlers arriving in America that we celebrate every year on Thanksgiving.
One of the things I was surprised by was how close in time so many of these famous astronomers and scientists lived. Its also incredible how accurate of observations these people were able to make given what they were working with. As I was learning about Galileo, it was really interesting to learn about how and when he was making his discoveries, but also a significant part of his life was dealing with the backlash. Galileo took a lot of inspiration from Copernicus’s heliocentric model, and indeed, some of his most important work was confirming this model. It was also fascinating to learn that it was due to his artistic background that he noticed the unevenness of the moon, due to the shadows that dotted it’s surface. Learning this about Galileo made me admire him much more as a pioneer in astronomy.
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Celestial navigation– also known as “astronavigation”– is a practice of nearly 4,000 years (HistoryHit, How Celestial Navigation Changed Maritime History) where an individual can determine their location in space or the Earth’s surface using the positions of other celestial bodies such as the Sun, Moon, other planets, and stars. Throughout history, this method has been primarily used by sailors in order to locate themselves without needing to map/track distances traveled. More specifically, celestial navigation makes use of angular measurements taken between a celestial body (such as the Sun) and the horizon (Wikipedia, Celestial Navigation), and uses these datapoints to narrow down one’s position. Much later in history, in 1757, an instrument called the “sextant” (GIF 1) was invented (Institute of Navigation, Sextant), and it allowed for far more precise measurements of the altitude of the Sun (to a precision of nearly one arc-minute), which greatly limited the measurements’ margins of error.
(GIF 1 from Nova Online) Depicts the use of a sextant, as well as the motion of its movable arm which serves to reflect the Sun’s light.
Through altering the position of the movable arm (also depicted in GIF 1), the referent object (in this case, the Sun) is to be placed on the horizon (Image 1). When the horizon and celestial object are aligned, one must read the angle in degrees and minutes of arc. Immediately after this, the user should note the exact time, which was historically done using chronometers (Wikipedia, Marine Chronometers). Finally, the individual must look at sight reduction tables, which are primarily used to obtain altitudes and azimuth angles (National Geospatial-Intelligence Agency). By (a) measuring this angle, (b) precisely recording the time, and (c) matching it on timetables existent at the time, navigators could map themselves on the surface of Earth without the use of modern GPS.
(Image 1 from WikiHow) Depicts the view through the eye-piece of a sextant aligning the Sun’s position with the horizon by altering the position of the movable arm.
Below (Video 1) is a video by the Collection of Historical Scientific Instruments that demonstrates how to use a sextant. Keep in mind that the sextant in use by the subject in the video is a modern-day sextant. Although its use was the same historically, the instrument’s capabilities became more and more refined as time went on (increased accuracy, better quality mirrors, etc.).
William Shakespeare – Arguably the greatest contributor to literature ever with with works like Hamlet and Romeo and Juliet
This time period was full of political and religious instability and violence, but yet so many of the world’s greatest minds were all alive during this time. My theory is that the pressure to get the upper hand on the rival countries created these great minds. There was more funding towards these exploratory activities. It reminds me of the space race. Innovation on that level does not happen too often, but when motivated to beat the Soviets America figured out how to send a man to the moon. Now no one has been to the moon for many years because there is no pressure or reason to spend money to go there.
Have you ever noticed that the moon seems different now than it did a week ago when you looked up at it?
The moon moves through several phases throughout the year, and this blog will help you understand why it appears differently at each stage of the cycle.
Why there’s different phrases?
Because of the angle at which light is reflected off the sun, the moon shifts its appearance on Earth. The moon’s position reflects the various expressions we encounter on Earth, even though half of its surface is always illuminated by light.
PHRASES
New Moon
Waxing Crescent Moon
First Quarter
Waxing Gibbous Moon
Full Moon
Waning Gibbous
Third Quarter
Waning Crescent
This entire circle takes roughly about 29.5 days to complete, in which explain why we can usually see new moon or full moon once a month.
Orbital of Moon and Earth
The Moon position shift across the sky within a year. The moon path is wrapped around the earth and earth orbit around the sun.
Tags: astro2110, intro
Tags: astro2110, intro
Posted inClass, General|Taggedastro2110, intro|Comments Off on Why The Moon Look Different Throughout the Year
Tycho Brahe was important in the history of astronomy. He created many new astronomical instruments and accurately calibrated them. Tycho was one of the first to correct for “atmospheric refraction.” In addition to this, he and his assistants discovered several anomalies that would lead to the future astronomical developments and models.
The French Wars of Religion between Catholics and Protestants began in 1562. These took place under King Henry IV and created a long-lasting conflict that sparked many more religious conflicts under French rule.
The invention of the pencil (use of graphite inside of wood) was in 1565. This was popularized due to a large lead discovery in England.
Michelangelo, 1475-1564 Michelangelo (death Feb 18, 1564) is a prominent figure of the Renaissance. He is known for sculpting, painting, engineering, and architecture.
Reflection
It is interesting to learn about the context of astrological developments. It helped me realize how recent what we know is. I found it very interesting that Tycho lived during the same time as popular Renaissance figures such as Michelangelo. While it makes sense in the years, before reading more, it felt like they were very different times. In addition to the Renaissance, placing astronomical figures in context allows people to understand how much of history the science people believed was incorrect. It makes me wonder if there is anything we believe today that will be proven false in the future.
Reflection Thinking about these other important happenings/individuals at the same time makes me consider how the evolution of modern thought (as well as the things we consider important/striking) didn’t happen as one-off events. Instead, a large portion of discoveries/developments can be said to have been enabled by other discoveries/developments. Because of this, we can’t consider ourselves fully satisfied with the understanding of only fragments of the development of science. In order to get a full picture, we must tap into the stories/concepts that influence the roots of our knowledge.
Have you ever heard of horoscopes, zodiac signs, or noticed you can see different constellations in the sky during different times of the year? This is all due to the shifting of our perspective on Earth throughout the year. No, the stars are not rotating around us out there. They are staying put as we rotate around the sun. This rotation around the sun changes our perspective because the Earth is tilted. As we rotate around the sun we end up pointing in a different direction in space during different seasons. As a result, in the northern hemisphere’s winter you would see constellations like Orion, and in the southern hemisphere, Orion would be only visible in the summer (which is at the same time as the north’s winter).
Throughout a year on Earth, the sun changes positions in the sky due to the 23.4 degree angle of our axis. The points at which the sun reaches maximum and minimum heights in the sky are called the Summer and Winter solstices while the points half way between are called the Fall and Spring equinoxes (Where each equinox has around 12h of sunlight all across the Earth).
In the northern hemisphere, the summer equinox occurs in June while at the same time the winter equinox occurs for the southern hemisphere (and vice versa in December.
Today in this blog post I will describe the size and scale of the universe from my understanding. To start off, light from the sun takes approximately 8 minutes to reach Earth, yet light from the farthest parts of the observable universe would take 13.8 billion years. Keep in mind, counting one billion seconds, one second per each number, would take nearly 100 years (34,722.2 days). In another scale such as the galactic scale, according to NASA’s Cosmic Distance Ladder, the Milky Way galaxy contains over 100 billion stars, with an estimated 2 trillion galaxies in the observable universe. With in these trillions of galaxies exists large voids out side of galactic clusters. As seen in the image above there is pockets density in the red and green and pockets of empty space between them, spanning hundreds of millions of lightyears.
