The 3 Laws that Govern the ENTIRE Universe

Posted on February 13, 2024 by sabrinaalperin

Illustration of Newton’s First Law of Motion

Have you ever wondered why spaceships do not rely on fuel once they are in outer space or why it is easy to throw a light object far but difficult to throw a heavy object far? At the end of the day, the answers to these questions boil down to Newton’s laws of motion.

THE FIRST LAW

Newton discovered that an object in motion will remain at the same velocity and that an object at rest will remain at rest unless it is acted on by a force. Imagine if this law were not true, your parked car in a parking lot could spontaneously drive off without you. This also answers why spaceships no longer need fuel in outer space. Once out of Earth’s atmosphere, which causes drag and friction, the spaceship maintains the velocity it is at since no forces act on it.

THE SECOND LAW

The force applied to an object is equal to the product of its mass and acceleration. Therefore, a lighter object can be thrown further since it has a smaller mass and therefore a greater acceleration. Mass and acceleration are inversely proportional in this law.

THE THIRD LAW

All forces have an equal and opposite reaction force. This means that for any force applied in a certain direction, there is a force of equal magnitude being applied in the opposite direction. In fact, you encounter this law in your daily life. When you sit on a chair, not only do you exert a downward force on the chair, but the chair exerts an upward force of equal magnitude on you. This is why a water bottle can sit on a desk and a pan can rest on a stove!

Posted in Class, Universe | Tagged , , | Comments Off on The 3 Laws that Govern the ENTIRE Universe

Blog 2 – Forecasting Tides

Posted on February 13, 2024 by James Bamshad

Image Source

Have you ever wondered how we predict the rise and fall of tides? Tides are driven by the gravitational forces of the Earth, Moon, and Sun, and has been a relevant subject to astronomers for hundreds of years. In a general sense, we are able to predict the timing of high vs. low and neap vs. spring tides based on the relative location of the Earth, Moon, and Sun. However, we can go further…

Through modern technology, we are able to actually predict what tidal patterns would be before they happen in specific locations. The NOAA (National Oceanic and Atmospheric Administration) has 3,000 locations along coasts all over the United States where they have collected and analyzed data to predict the severity and variation in tides. The NOAA Tide Predictions interface allows users to select a specific tide station and generate tide predictions for the current day and the following day. Users can customize the predictions by adjusting parameters such as the begin date, time range (daily, weekly, or monthly), time zone, and units of measurement (feet or meters)

Meanwhile, tide-predicting machines (pictured below), marvels of the late 19th and early 20th centuries, were earlier tools for forecasting tidal patterns. The first tide-predicting machine, created in 1872–73, and later improved with two larger versions in 1876 and 1879, was developed by Sir William Thomson. These machines mechanized the laborious computations involved in tide prediction.

Image Source

Posted in Moons | Tagged , , , | Comments Off on Blog 2 – Forecasting Tides

Blog 2

Posted on February 13, 2024 by Leni Ertel
timeanddate.com

The force of the moon’s gravity on earth causes tides. Due to the difference between the strength on the moon’s force on different parts of the earth, a tidal force is created. This tidal force, could also be referred to as a “stretching force,” as it creates two tidal bulges, with one being larger on the side of earth that faces the moon (Bennett et. al, pg. 128).

Not only is there a tidal effect on the moon, there is a tidal effect on the sun. The gravitational force between the sun and the earth is much stronger than the force between the earth and the moon, due to the sun’s large mass. However, because the distance between the earth and the sun is so great, the pull between the different sides of the earth is quite minimal. The tide force caused by the sun is less than half of the force caused by the moon (Bennett et. al, pg. 129).

When the tidal forces of the sun and moon work in tandem, we get spring tides, which are pronounced. We see this at new moon and full moon. When the tidal forces of the sun and moon counteract each other, we get neap tides, which are relatively small. We see this at first-quarter moon and third-quarter moon (Bennett et. al, pg. 129).

Posted in Class | Tagged , , | Comments Off on Blog 2

Observational Limitation, Scientific Innovation

Posted on February 12, 2024 by John Newell

Our telescopes just keep impressing.

There are just so many limitations, on a physics level, that prevent us from observing the Universe around us. Telescopes are hindered by light pollution and atmospheric disturbances on Earth, preventing them from peering into extreme distances. In space itself, obstructions such as gas clouds block our view of more distant, and perhaps interesting, objects. The size of the observable Universe, and its accelerating expansion, puts a hard cap on how far we can see. We are limited by the size of our telescopes — to view the supermassive blackhole at the center of the galaxy M87, one requires a telescope with the diameter of the Earth itself.

To each of these problems, though, humanity has responded with unbelievable innovation. Clever software and remote locations have reduced hindrances to observation on Earth. Even more impressive is our launching of our telescopes into space — most famously Hubble, and most recently, JWST (which sits an an unbelievable 1,000,000 miles away). To peer through gas clouds, our telescopes view different wave lengths, like gas-penetrating infrared. And to view extremely distant objects like M87, we use a series of telescopes all over the world, sci-fi like accuracy of time measurement, and innovative software to create our first picture, and undeniable evidence, of a black hole.

Black Hole in M87, Event Horizon Telescope
Main mirror assembly from the front with primary mirrors attached, NASA November 2016
Hubble Deep Field, NASA

The Universe has provided us with countless obstacles to unlocking its secrets. But, so far, scientists have improvised, adapted, and overcome.

Posted in Class, Science | Tagged , , , | Comments Off on Observational Limitation, Scientific Innovation

Light and the Electromagnetic Spectrum – Blog 2 – Cameron Klein

Posted on February 12, 2024 by Cameron Klein
HubbleSite

Before enrolling in this course, I had given no thought as to what light truly was. To me, light simply stemmed from the light switch on my wall as I flicked it on and off. However, there is so much more to light than what first meets the eye (no pun intended). According to the The Cosmic Perspective by Jeffrey O. Bennett, Megan O. Donahue, Nicholas Schneider, and Mark Voit, Newton correctly inferred that light was made up of tiny particles, though he didn’t know quite what. The first component of light that I would like to highlight are waves. There are many types of waves, including radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays. All of these waves have different properties, and some are visible to the naked eye, while many are not. Waves are often characterized by their peaks (uppermost parts) and troughs (lowermost parts). However, although waves move outward, the particles within them move up and down. Another term important to the conversation of waves is wavelength. Wavelengths describe how long a specific wave is by illustrating the distance between peaks and troughs. Additionally, frequency is characterized by the number of peaks passing by any given point each second. Then, when we multiply wavelength by frequency, we get speed. The speed of waves is the distance that the waves traveled in a specific amount of time.

Now that you have a decent groundwork for what light is, we can begin our discussion of the electromagnetic spectrum. The range of colors that we can see with our eyes is only a tiny part of all of the light in the universe…or, in other words, the spectrum of light. Hence, the use of the term: electromagnetic spectrum. Though it is difficult to fully grasp, there is light beyond the rainbow that we are unable to see. The form of light in which we are able to see is dubbed visible light. Virtually, these are the colors of the rainbow. Colors between about 400-700 nanometers make up the colors of the rainbow. Light with wavelengths of just beyond 700 nanometers (what we see as red) are called infrared light. Just beyond infrared light are microwaves, and then we move to radio waves, which are the longest wavelength-light. Then, moving along the spectrum in the other direction, if a light is just shorter than 400 nanometers, it is considered ultraviolet light. Ultraviolet light can be extremely damaging, causing sunburn and even skin cancer. Light with shorter wavelengths are x-rays and the shortest wavelength-light are gamma rays. I hope that this helped to lay the foundation of light and the electromagnetic spectrum for you!

Posted in Light | Tagged , , , | Comments Off on Light and the Electromagnetic Spectrum – Blog 2 – Cameron Klein

Ancient Structures

Posted on February 12, 2024 by Maddy Pollard
Stonehenge

Many people have heard about Stonehenge, one of the world’s most famous monuments. But did you know that the circle of stones was actually an astronomical device? Archeoastronomists have debated what the original purpose of Stonehenge was, but many believe that it was used to mark solar and lunar alignments, including eclipses, solstices, and equinoxes. Many other ancient cultures built structures for astronomical purposes. Another famous example is the Templo Mayor, built by the Aztecs in modern-day Mexico City. This structure was built so that the Sun would rise right in between the two temples on the equinoxes. A third famous structure is the Sun Dagger, which is found on the Fajada Butte in New Mexico. This special structure, made up of three slabs of rock leaning against a cliff, show different patterns of light based on the time of year. For example, sunlight shines through the rocks and produces a single “dagger” on sunlight only on the summer solstice. These structures were a way for ancient civilizations to mark special dates, such as solstices and equinoxes, as well as keep track of the seasons. It’s interesting to see the different structures each ancient civilization thought of to measure the same astronomical events. Unfortunately, many of these ancient structures have either shifted or been destroyed and no longer serve their original purpose. They are still cool to learn about though!

Posted in Historical | Tagged , , | Comments Off on Ancient Structures

Justin's Blog 2024-02-12 17:22:51

Posted on February 12, 2024 by Justin Kim

History of Astronomy in Korea!

Hey everyone !

Do you guys remember when we were learning about historical astronomical sites in class? I remember one of the sites catching my eye because it looked incredibly familiar. It was the one in Korea called Cheonseongdae in Gyeongju, South Korea. I once visited this while on a trip with family and friends when I was much younger but seeing it again sparked so many memories. Learning about how old it is amazed me because its so well preserved.

This astronomical site is considered to be one of the earliest in East Asia (maybe the entire world). It is believed to have been constructed in 647 C. E. This observatory may have been used to make astronomical observations to plan agriculture. There is a lot of disagreement around Cheonseongdae because there is no clear documentation about how it was once used. Some believe that this site is simply an altar to pay tribute to the god of agriculture. This is like the Stone Henge of Asia.

Source: Cheonseongdae

Posted in Class, Historical | Tagged , , | Comments Off on Justin's Blog 2024-02-12 17:22:51

A tidal bore worth traveling for

Posted on February 12, 2024 by Angela Harris

Mont Saint-Michel at high tide

Chapter 4 of the textbook explained how the Moon and the Sun affect ocean tides. We learned that the timing and height of tides at a given location depends on its latitude, the orientation of the coastline, and the depth and shape of any channel the tide has to flow through. The book gave an example of a location with an unusual tidal pattern; the incoming tide at the abbey of Mont Saint-Michel in Normandy, France.

The difference between low and high tide at Mont Saint-Michel is up to 15 meters which makes it one of the highest tides in Europe! The tide rises faster than people can swim, but many kayakers enjoy the strong current!

If you were planning a trip to Mont Saint-Michel to see the impressive tidal bore, you would want to consider a few factors. Since it is a spring tide, you would want to visit during the New Moon or Full Moon (the strongest tide is usually 36 to 48 hours after). You could also use this tide forecast to pick the best day, time, and viewing site! Would you travel to Mont Saint-Michel or any other famous tidal site to see the tidal bore in person?

Kayakers enjoying the strong current in the Mont Saint-Michel Bay!

Other source: Textbook chapter 4

, , ,
Posted in Class, Moons, Science | Tagged , , , | Comments Off on A tidal bore worth traveling for

Blog 2: Tides

Posted on February 12, 2024 by Charles Knoll

Tides represent the ebb and flow of ocean waters, orchestrated by the gravitational influences of both the moon and, to a lesser degree, the sun. As the moon orbits the Earth, its gravitational force interacts with our planet. Despite the moon’s relatively small mass, its gravitational pull, although not immense, varies across the Earth’s surface since there is a difference in distance. This variance creates what is known as a “stretch force” or tidal force, resulting in two tidal bulges—one facing the moon and another on the opposite side. This stretch is akin to the effect of stretching a rubber band. 

Furthermore, although the sun’s gravitational pull is significantly stronger due to its larger mass, its impact on tides is minimal. The slight difference in gravitational force across the Earth’s diameter fails to produce a noticeable tidal bulge. However, when the gravitational forces of the moon and sun align during specific lunar phases, such as the full and new moons, they combine to generate larger tidal variations, known as “spring tides.” Thus, while the sun may not directly create tidal bulges, its synchronized alignment with the moon amplifies tidal changes.

Source: Photo

Posted in Science | Tagged , , , | Comments Off on Blog 2: Tides

Blog Post 2: How Tides Work

Posted on February 11, 2024 by Nicholas Fleisher

Chapter 4 of the textbook provided a detailed analysis of how tides are the result of the gravitational attraction between the earth and moon. In my blog post, I’d like to demonstrate my knowledge of the subject matter in preparation for the upcoming test in order to solidify my understanding of the matter.

As stated, tides are the result of gravity attracting the moon and earth together. The gravitational attraction of each part of the Earth to the Moon becomes weaker as we go from the side of Earth facing the Moon to the side facing away from the Moon. This difference in attraction creates a sort of “stretching force” or tidal force, that stretches the entire Earth to create two tidal bulges: one facing the Moon and one opposite the moon.

I appreciated the analogy provided that compared this to a rubber band being stretched. The earth is stretched on both sides of the rubber band even though the Moon is tugging harder on only one side.

So, the tides are created by the difference in force of attraction between the Moon and different parts of Earth. There are two daily high tides that occur as Earth rotates through the two tidal bulges. Low tide occurs when the location is at the points halfway between the two tidal bulges. The tidal cycle of the two high tides and two low tides takes about 24 hours and 50 minutes, so each high tide occurs about 12 hours 25 minutes after the previous one.

The sun also exerts tidal force on the Earth, causing Earth to stretch along the Sun-Earth line. However, the gravitational force between Earth and the Sun’s mass is much greater than that between Earth and the Moon, which is why Earth orbits the Sun. Overall tidal force caused by the sun is less than half of that of the moon because of the relative distance between the two pairs.

Because tidal forces stretches Earth itself, the process creates friction, called tidal friction. the effects of this are that the Moon’s gravity always pulls back on the bulges, slowing Earth’s rotation. The gravity of the bulges also pulls the Moon slightly ahead in its orbit, adding orbital energy that causes the Moon to move farther from Earth.

The concept of tides also relates to the conservation of angular momentum principle because the Moon’s growing orbit gains the angular momentum and energy Earth loses as its rotations slows. Source of image

Posted in Class | Tagged , | Comments Off on Blog Post 2: How Tides Work