Over the past few classes we have talked about waves, light, and spectrums. We did a tutorial in class with diffraction gratings that allowed us to see the light spectrum coming off of different light sources that we had in class. We learned that light emitted through different gasses gives off a different spectrum. We also did a couple pages in the workbook that taught us that radio waves have the lowest frequency in the electromagnetic spectrum of light, while gamma rays have the highest frequency. Lastly, we learned about the doppler effect and that when an object and a light source are moving toward each other, the light undergoes a blueshift. When an object and a light source are moving away from each other, the light undergoes a redshift. This is why when an ambulance passes by, the sound it makes seems to change pitch from when it is coming towards you and when it passes you.
I found the article “This Is the Purest Beam of Light in the World” on Space.com
This article talked about how a team of scientists at MIT have made the purest laser in the world. This device produces a beam of light that changes less over time than any other laser in the world. Usually, temperature changes and other environmental factors cause laser beams to wiggle between wavelengths. This so called wiggle is a change in the beam’s linewidth. Reducing this linewidth makes this device the most accurate laser we have, which will in turn give us more accurate data.
I thought this article was a good choice for this conceptual objective because it talks about a beam of light and its wavelength, much like what we have been talking about in class. I found this article interesting because lasers are cool. Who doesn’t like lasers..?
During the course of objective 7, we learned how astronomers use light to determine the chemical composition, the speed, and the direction of an astronomical object’s motion. In class we learned about the Doppler effect. The Doppler effect is the increase or decrease in frequency of sound, light, or other waves as the source and observer move toward or away from each other. We talked about Discrete spectrum and how each atom has its own set of energy levels, as well as each atom, generates photons at specific frequencies. The pattern of frequencies identifies the atom, two examples: neon or mercury light. We learned about the different spectrums that include: continuous spectrum, dark line absorption spectrum, and the bright line emission spectrum. We also learned about Margaret Huggins and her contributions to Astronomy. Margaret and her husband were pioneers in the field of spectroscopy, that is the study of spectra. Margaret used photographs and drawings of spectra to study objects in space. Spectra was used to learn about the sun, other stars, and nebula.
We did a tutorial on page 63 that helped us learn about the three different kinds of spectra discussed during objective 7 (Continuous Spectrum, Emission Spectrum, and Absorption Spectrum). This tutorial taught us how the density and the energy source of something determine what kind of spectra it falls under.
I found this article on spectroscopyonline.com that discusses a kind of spectroscopy that is used in the real world, that is making recycle sorting much safer. The method that is discussed is using hyper spectral imaging to differentiate between different plastics and flame retardants within them with 100% accuracy. This will not only make sorting flammable plastics easier, but it will also make it more efficient by making it faster. To meet safety standards, flammable recyclables must be removed before recycling can take place. With recycling becoming more efficient thanks to this method, our environment can also benefit from getting trash taken care of sooner than later.
I found this article interesting because we learn how astronomers are able to us spectrography to study space and objects in space, but we did not really cover other methods of using spectral imaging outside of astronomy. I think it is important to always progress and improve on finding new methods to take care of our environment. A personal story I have that relates to this article just happened 2 weeks ago. I was driving on Ridge Road in Minooka and there was a garbage truck just before the Pilot gas station that had the trash from his truck on the street. All the trash he had collected had caught fire and to keep his truck from catching fire, he dumped the trash onto the road. These kinds of hazards can also occur at recycling centers. Methods like using spectral imaging can help make these centers more safe and make everything more efficient.
We talked about planetary seasons. Planetary seasons are of course different than seasons here on Earth. Seasons and weather vary from planet to planet. This is because here on Earth we experience seasons differently based on the sun’s energy. The Earth spinning revolving around the sun obviously is the reason why weather in Australia to North America can very so much.
This article is about spring on other planets, specifically weather on Pluto being spring since 1990. It goes onto to explain as I just did we owe the seasons to Earth’s axis. We experience spring every year but on Pluto it has been spring for 29 years (at least on the northern hemisphere). It is quite interesting that though this dwarf planet is so far from the sun it has been interlocked in a spring state. Pluto can actually get so cold that its atmosphere freezes and falls on the surface since it is so far from the sun.
Spring on Neptune is twice as long, Saturn has spring just like us, Jupiter does not have spring at all, Mars and Earth, although similar in size, experience seasons very differently due to Mars’s axis being tilted differently. The concept of interstellar seasons is crazy and I’m glad I got to learn more about the topic.
We started the semester by learning a basic topic, position and motion. This deals with the Earth’s rotation causing stars, the sun, and other planets in the solar system to look like they are setting and rising depending on the time of day. The Earth’s rotation causes the stars to vanish and appear. Obviously in some locations of the solar system some stars can be seen that can be seen from Earth for example.
In class, we worked in our lecture tutorial book in the very beginning of the book starting on page one. The workbook gave us an overview of a “space-eye” view of the solar system. It really put things into a more visual perspective, making it easier to understand.
As you warned in class, this topic was a bit hard to find an article for but after some searching, I think this was a good pick. The article talks about us being able to see the Moon “swallowing” Saturn. Of course the stars change within the universe but only on timescales much greater than a human would understand.
“But that’s no moon, of course; it’s the planet Saturn! From about 3:00 AM to 5:00 AM (Universal Time, or UTC) on Friday, March 29, Saturn and the Moon will appear to get closer and closer to one another in the night sky, which will look incredible through either binoculars or a telescope at very low magnification with a Moon filter applied.”
Those who decide to wake up this early will catch the rare sight of Saturn in the distance appearing to be “swallowed” by the moon. But not to fret if you’re up around 1 AM you could also catch a glimpse.
We kicked off the semester learning about motion and position in relation to astronomy. Part of what that mainly entails is the fact that the earth’s rotation is what causes other planets in our solar system, as well as the stars, and sun to appear to be rising and setting as the day goes on. We discussed how not everyone on the planet earth can look up at the sky and see the same thing, when a person is standing on the earth’s surface they are creating an imaginary plane as well as a horizon, when stars appear above the horizon they are now in view of said observer, and contrary when stars fall below the horizon they are no longer in view due to the earth being in the way. Not only that, but since it is the earth’s rotation causing the stars to “appear” and “disappear” only certain stars can be seen from certain hemispheres at a time, although there are certain instances in which a constellation or stars can be seen year round in an area.
In class we used the workbook and the diagrams in pages one through six to better put a visual to what we were learning. The workbook basically gave us a space eye view of the earth and an imaginary horizon from an observer on earth to better understand as to why only certain parts of the sky can be seen at a time and naturally due to the earth’s massive size being in the way. The workbook also got us into some deeper thinking like in question 7 when it asks at what positions does star B rise or set and it was actually a little bit of a trick question because it is a circumpolar star so it will never rise or set due to its proximity to either the north or south pole. Lastly the workbook helped us learn as to where one might need to look and face to see stars in relation to their position on earth like on question 10 on page 2.
Admittingly this topic was a little harder to find an article for but I chose this one due to its relation to the stars. Looking up at the night sky can be one of the most rewarding things when you realize there are billions of beautiful stars up there. Unfortunately sometimes it can be difficult to see all those stars or even one, whether it be because of a cloudy night, light pollution from humans, or simply not being on the right part of the planet at the right time, but fear no more! You now no longer have to turn off the porch lights and head outside necessarily to get a view of the stars thanks to a new star map! The European spacecraft Gaia, gave us the most detailed map of our galaxy yet showcasing billions of stars in a 3D map. I picked this article because now anyone can access and download the map and use it to study astronomy as they please, and since within the first few hours of launch thousands of people already began to download the data, it’s exciting to think what might come of it!
Learning about position and motion gave me a much better understanding of how we move on this floating space rock. While I always knew that it was the earth that was rotating, not the sun I never really understood how the stars worked and how people were able to map out constellations as well as where they will be appearing. Now I know that throughout the year and earth’s orbit around the sun, different constellations can be seen while some can be seen year round!
Objective 7 was all about being able to explain how astronomers use light to determine the chemical composition, the speed, and direction of an astronomical object’s motion. We started off this objective by taking notes about the properties of light (speed & energy) and what is included in electromagnetic radiation (radio waves, visible light, and gamma rays to name a few). We also learned about wavelength, frequency, and speed because it has to do with light as electromagnetic waves. Photons play a role in this as well because electromagnetic radiation is carried by them. Planck’s law relates to this because it says that the frequency of an electromagnetic wave is related to the energy of a photon. Then, we talked about the 3 different types of spectra which are: continuous spectrum, emission spectrum, and absorption spectrum. We did a lecture tutorial called, “Types of Spectra” to help determine the differences between them. Within this tutorial, I learned that a continuous spectrum is produced when light is emitted directly from a hot, dense object that passes through a prism. An emission spectrum is produced when the light is emitted directly from a hot, low-density cloud of gas that passes through a prism. Finally, an absorption spectrum is produced when light goes through a hot, dense energy source and passes through a cool, low-density cloud through a prism. Also, we talked about Doppler Effect and did another lecture tutorial called “Doppler Shift” that really helped because it had a bunch of different diagrams/images teaching us how to apply the same idea. I learned how to look at a diagram and determine which star is not moving, as well as how much it has shifted. Blueshifted means that the observer and the source of the light are moving toward each other, so the light is shifted to shorter wavelengths. Redshifted means that the observer and the course of light are moving away from each other, so the light is shifted to longer wavelengths.
This article talks about how we may have witnessed the birth of 3 giant planets forming through a picture provided by Atacama Large Millimeter/submillimeter Array (ALMA). They observed signs that there were 3 massive planets forming around a young star near our cosmic neighborhood. Astronomers used the same technique to study these planets as if they were searching for other newborn worlds. It’s used to see how clouds of gas and dust turn into the Solar System. They decided to name this important star HD 163296. It is a very young star in the cosmic world because it is only 4 millions years old. Researchers used ALMA to snap intricate photos of the disk of dust surrounding the star, where it showed the 3 gaps. Carbon monoxide was what was within the disk, so they studied the motion of the gas to find out that it was being moved by giant objects resisting in those gaps (sign of newborn planets). This is where ALMA, an observatory in the high-elevation Atacama Desert in Chile, comes in. They use 66 individual telescopes to observe light around one millimeter in wavelength, somewhere between infrared and microwave. This specific type of light is the most appropriate for studying newborn planets because it clearly shows where dust and molecules live. Specifically, astronomers used ALMA to study the flow of carbon monoxide molecules in the protoplanetary disk around HD 163296. CO is a very common gas found in many interstellar clouds. They continued to measure the speed of the carbon monoxide by using the Doppler effect. This applies because the motion of the molecules created a shift in the wavelength of light emitted by the CO. The astronomer discovered that the gas was not just orbiting this star, but also being pulled toward the objects hidden in the gaps of the disk. Overall, ALMA was able to measure this very accurately because of the Doppler effect (a few meters per second).
ALMA image of the protoplanetary disk around the star HD 163296. The gaps in the disk are where three newborn giant planets are hiding.
As soon as I saw the title of this article, I knew I had to read it because we talked about the Doppler effect quite a bit. We even did a lecture tutorial that was called, “Doppler Shift.” So, I knew it had to correlate with this objective, and it did. It was a very interesting read because it mentioned that capturing the image I inserted above, is very rare. I am always intrigued when something is said to be rare because it already amazes me that we are able to capture all sorts of things like this that happen in our solar system. This article was a great way to apply the Doppler effect to a real life event, and I think it helped me understand it much better. It’s interesting to think that if ALMA was not a thing, then we may not have caught this and been able to experience and observe such a cool thing. Looking at the picture, it was hard to grasp the fact that there are 3 planets hiding in the gaps of the disk because it just seems as if it’s too small, but things in space are extremely massive so it’s just mind-blowing to me. I really enjoyed reading this article because it was very descriptive and easy to understand, without being excessively long and including unnecessary information.
This article is about how light does not stay it’s normal way. Physicists build a ring shaped machine that makes light circle each other. When light moves forward and backward in the same way it is in time reversal symmetry. When light is going in motion of a wave it is going through polarization. In the device, light loses it time reversal symmetry and polarization. As the physicists put a laser light beam into the device, the light losed it’s vertical polarization when the light waves stopped moving up and down.
This article relates to how light determines the chemical composition, the speed and direction of an astronomical object’s motion by the light’s direction changed when the time reversal symmetry and polarization was impacted. The speed of the light depends on how the physicists manipulate the light. In class when we did the lecture tutorial on page 63 of Types of Spectra, the image that is shown in the article reminds me of a continuous spectrum because the light comes out of a hot, dense energy source that passes through a prism that produce the colors: red, blue, and green.
When I read this article I learned that you can manipulate light with it’s direction. I learned that light does have different symmetry through time reversal symmetry and polarization that can be changed by a laser light. The energy of the laser light can be powerful that regular light stop it’s motion. I learned that this concept determines how high your energy source has to be to produce a spectrum.
In the previous classes we learned about Newton’s Laws. Newton made explanations and explained acceleration. Newton came up with three laws that are still being used today. To help us get a better understanding of Newton’s Laws we did lecture tutorials on Newton’s Law and Gravity on pages 29 through 32.
The first law is an object in motion will stay in motion unless acted upon
Newton’s second law is an equation to solve for force. EF=ma. M stands for mass and a stands for acceleration.
Newtons third law states every force or reaction has an equal opposite reaction.
An article I read was from space.com and it focuses on Newtons second law. NASA astronaut, Randy Bresnik, does a fascinating experiment. He launches chapstick and a bag into space. The chapstick went flying a lot faster than the bag because the chapstick weighs a lot less and its acceleration is able to increase much faster. The article also explains the heavier the spacecraft is, the more force it needs from engine thrust to start accelerating.
I found this article to be very helpful because it gives me a real life example of Newtons second law. Not only does the article talk about the experiment, but they also show it. I thought this article was very interesting and definitely worth watching and reading it!I also enjoyed how Newtons laws are still being used today.
Objective 6: I can apply Newton’s laws of motion and Newton’s law of universal gravitation. Recently in class we have been talking about Newtons three laws of motion and how they work. Newtons first law is that an object at rest will stay at rest unless acted on by an external force. Also, an object in motion will stay in motion unless acted on by an external force. Newtons second law states, force is equal to mass times acceleration. Lastly, his third law states, every motion has a opposite or equal reaction. Those three laws make up our foundation on motion. Also, we talked about Newton’s law of gravitational force, which is the force between any two masses, the equation is F=G(m1)(m2)/r(r). An example of how we worked on these laws in class was when we worked in our lecture tutorial workbook on page 30. Problem 2, we had to chose which student was using Newtons Law in the right way and it helped me understand the law a little better.
The article highlights Newton’s second law of motion by sending three objects into free flight inside the International Space Station. There is also a video of NASA Astronaut Randy Bresnik demonstrating the law on the ISS. In the video, Bresnik uses a bendy slingshot to put a ChapStick, a miniature replica of a space capsule and a large stuffed storage bag all into motion. Sure enough, the ChapStick goes flying faster than the big bag, because if the force acting on the object remains constant in all the examples, the larger object will not be able to accelerate as much.
I thought that this article was very cool because it showed how Newtons law actually works in space. Also, it was very cool to see an astronaut on the ISS doing little tutorials.
When the apple fell on his head, Newton realized that it was the same force that held the moon’s orbit around the Earth- gravity. He was the first to recognize that the force of gravity works in the entire universe, as well as on Earth. For this objective, I found an article about how Newton’s three laws of motion explain astronauts’ movements in space. It gives great examples of how astronauts must remember these rules if they want to stay away from losing their things, getting bruised, and moving in ways they weren’t expecting.
“Working in Zero Gravity” Image courtesy of ESA.INT.
The display of Newton’s first law in this article is when an astronaut put his pencil down, and it continued to stay in motion- floating further away from him. Newton’s First law of motion states that in the absence of a net force, in this case the astronaut’s grip, objects in motion tend to remain in motion.
Newton’s second law of motion is prominent when astronauts begin to move around the spacecraft. Using their own body weight and force, they are able to accelerate in the direction in which they are applying their force. Because the equation force = mass X acceleration holds true, it would then be ideal that a heavier and stronger person would move with much more acceleration than a smaller and much weaker person. Astronauts have to get used to pushing themselves around, experimenting with the amount of force they exert to get to where they need to be. They also have to remember to stop themselves otherwise the law states that they will stay in motion- leading to them bumping into a wall or something else.
Lastly, Newton’s third law of motion is important for astronauts to be aware of because if they do not ground themselves against the wall, any force that they exert will come with an equal and opposite reaction force. The article states, “if they so much as try to turn a screw without anchoring themselves to a wall, they’ll find themselves twisting instead.” The force the astronaut exerts while turning the screw is equal to the screw’s force on the astronaut, making the astronaut move in such a way.
In the end, this article gave many interesting examples of how Newton’s laws aren’t only applicable to Earth, they also apply in space. In the lecture tutorial pages 29-32, I’ve learned many things about the force of gravity to help me better understand the 3 laws of motion. Specifically, part II gives a great example of gravity in space that gave me an idea of what kind of article I wanted to look for.
Joliet Junior College - Astronomy 101 class blog 