Because of this class my view of the solar system has changed. From a young age I knew the order of the planets and even some basic facts about each of them. What I did not know, however, was how much more there was to know not only about our solar system, but about the vast number of stars in our galaxy and the current work being done to find extra-solar planets. I have learned so much more information about what goes on inside the planets as well as the fascinating moons that particularly Jupiter and Saturn have. It has also been so interesting to see how the physics class I am currently in and this class coincide. On practically the same day we learned about magnetic fields and how they protect the Earth from charged particles from the sun. Similarly, we learned about Jupiter’s magnetic field and how the tidal forces brought about the volcanism of Io on the same day in Physics and Astronomy. This really excited me about the future classes that I want to take that are about the physics of astronomy. Hopefully through taking these classes I would be able to more fully understand the current work that is happening in the search for exoplanets and in the continued search for an answer to the mystery of dark matter and dark energy, a field that is so fascinating to me.
Blog 6: The Fermi Paradox
The Fermi Paradox is the apparent contradiction between the lack of evidence for extra-solar civilizations and the fact that there is a high probability that many Earth-like planets exist that are older than ours and that it would conceivably be possible to explore the galaxy in a couple million years. Simply stated, where are the aliens because they should be here. There are many hypotheses for why this may be the case. Some deal with the nature of civilizations, the nature of the universe, and even conspiracies the aliens have been found but the government is hiding this from us. Here is a list of all the hypotheses that Wikipedia summarizes:
One of the ones I find most interesting is the hypothesis that they are too alien. This one states that the difference between us and other life could be so extreme that communication is all but impossible. Perhaps these aliens think and communicate so much slower than us that we would mistake communication for background noise. Or perhaps these aliens understand physics and math completely differently.
In general, I find the fact that the life on Earth is the only one that we can base any hypothesis on to be most limiting factor in any search for extra-solar civilizations. Given that we have no other examples of life to base our thoughts on, our search for life is greatly inhibited by this lack of understanding. Additionally, we don’t even understand how we got here in the first place, what lead to eukaryotic cells and sexual reproduction, thus it is pretty difficult to postulate what other civilizations would be like. However, these limitations certainly don’t mean we should stop searching. In fact they are motivations to continue searching because perhaps an answer to life elsewhere would lead to answers about the nature of life of earth.
Blog 5: TESS
NASA’s new exoplanet telescope, the TESS (Transiting Exoplanet Survey Satellite), was launched April 18, 2018 and is expected to find 20,000 exoplanets during its 2 year primary mission. This is huge increase compared to the 3,933 that are currently confirmed. Among these planets will hopefully be multiple rocky planets in the habitable zone, or zone where liquid water can exist. TESS is sensitive enough to see planets a little bigger than Earth for perhaps 1,823 stars and Earth sized ones for 408 of them. In an article by NASA, Lisa Kaltenegger is quoted explaining that “life could exist on all sorts of worlds, but the kind we know can support life is our own, so it makes sense to first look for Earth-like planets,” thus explaining why the data of these planets in the habitable zone are garnering special attention.
A fascinating detail about the TESS satellite is its orbit. It is in a highly elliptical orbit that’s apogee is almost as far away as the moon and perigee that comes as close as 108,000 km (about 3.5 times closer). TESS is in a 2:1 resonance with the moon, meaning that it orbits the Earth twice for every moon orbit, and is timed to be about 90° away from the moon thus minimizing the moon’s interference in TESS’s orbit.
Blog 4: Humans back on the Moon and on to Mars
NASA’s plans for sending people to Mars are intertwined with their plans to send humans to the Moon more consistently, and hopefully to be able to establish a human presence their within the decade. They plan to launch the Gateway, a spaceship that will orbit the moon to support future trips there. They plan to launch it in 2022. By having people live on the spaceship they can better understand “how the human body responds in a true deep space environment before committing to the years-long journey to Mars”.
SpaceX wants to establish a Mars base in the 2020s and plans to launch cargo flights by 2022. This seems a little ambitious to me, though granted I don’t know how long this has been in the works; however, I’d imagine it takes a very long time to design, plan, launch, and travel to Mars especially given NASA’s timeline and the 34-million-mile distance to Mars.
Blog 3: Auroras in the Southern United States
On November 20, 2003 Auroras were seen in the southern United States. This is not a normal occurrence as is likely obvious to most of you. Auroras, or the Northern Lights, are caused by charged particles from the sun spiraling around the earth’s magnetic field and hitting the atmosphere. The magnetic field lines of the Earth are only close enough to the atmosphere for this to happen at the poles. However, in 2003 a coronal mass ejection(CME) disrupted the magnetic field of the Earth near the southern United States. This allowed charged particles to go through this new hole in the magnetic field and slam into the atmosphere thus causing Auroras in the south.
A coronal mass ejection is a huge (a billion-ton) cloud of gas that comes from an explosion on the sun. It also has a magnetic field that when oriented right can cancel out the Earth’s. In this particular instance the CME and the explosion was medium sized, so not very intense or dangerous to satellites, and yet it produced an amazing spectacle which I hope to one day be able to witness.
Blog #2: Special Relativity
Albert Einstein was one of the most influential thinkers regarding the fabric of the universe. Einstein’s major contribution to modern physics was his theory of relativity. The first part of this revolutionary idea was his special theory of relativity. Published in 1905, it established two major points: the laws of physics are the same in any inertial frame and the speed of light is always constant no matter the speed of the source or the observer. While the theory most directly dealt with physics on a microscopic scale, it still had many major implications. His first point dealt with the idea of relative motion and the fact that there was no ether, a nonmoving frame of reference, that all previous physics was based upon. The ether was an important idea in the belief that the universe was orderly and structured. The new idea of relativity where there was only relative motion rather than absolute motion unraveled this idea. There was nothing absolute. His second point about the consistency of the speed of light is a bit more difficult to understand; however, it constitutes the idea of a curved spacetime, something that was explained more elaborately in his general theory of relativity. The idea of time as a dimension that, along with space, could be warped showed that we did not live in a universe of the orderly Euclidean geometry but in a non-Euclidean universe. These concepts unraveled the prevailing idea that the universe was fundamentally structured and worked according to Newton’s orderly laws and vaulted scientific thought into a whole new era.
Sources (from research I did in high school so I couldn’t hyperlink them):
“Relativity” World Book Encyclopedia. 1989.
Pearce Williams, L. “Ether.” Encyclopedia Americana.Scholastic Grolier Online, ea.grolier.com/article?id=0147190-00. Accessed 15 Feb. 2017.
Will, Clifford M. “Relativity.” Grolier Multimedia Encyclopedia.Scholastic Grolier Online, gme.grolier.com/article?assetid=0244990-0. Accessed 16 Feb. 2017.•
Historical Astronomers in Context
15 February 1564 – 8 January 1642
Galileo Galilei was extremely important to astronomy. He made some adaptations to telescopes and then used them for studying the stars. Thus, he was able to much more closely and precisely objects in the sky. He observed sun spots on the sun, proving it wasn’t perfect and thus that the objects in the heavens were not all perfect. He also overturned Aristotelian physics by showing that objects in motion stay in motion thus birds and clouds won’t fly off the Earth if it was moving. Finally, he saw the phases of Venus that would only make sense if the Earth was orbiting in the sun.
Events During Galileo’s Lifetime:
The Spanish Armada occurred during Galileo’s lifetime. The Spanish fleet of ships were defeated by the British, beginning of the end of Spanish power in the world.
The 30 Years War also started during his lifetime. It was a basically a war between Catholics and Protestants that occurred in four stages: Bohemian, Danish, Swedish, and French.
People During Galileo’s Lifetime:
Charles I of England. He ruled without parliament until 1642 when he was beheaded during the English civil war. His beheading was after Galileo died, but Charles I reigned while Galileo was alive.
It was very interesting to figure out what was going on in the world when these astronomers were doing their work. It is easy to think of these people as isolated and not really a part of any time period, so it was cool to see that there were wars and things of great historical significance happening while these astronomers were alive. It makes them seem more like people rather than just the work they did.
Blog #1: Solar Eclipse Calendar
A solar eclipse is when the moon comes between the sun and the Earth and completely or partially blocks the light from the sun. This can only occur when the moon is at the nodes of its orbit and when its precession allows it to be in this position while being between the sun and Earth. Angular eclipses are when the moon is at its apogee and thus never covers the sun completely. However, at the moon’s perigee it is 400 times closer than the sun but 400 times smaller in actual size and thus can perfectly cover it. I did not get to see the “great American eclipse” because of a prior commitment, so I am very interested in finding the next total solar eclipses that would be easy to go to. I am not particularly interested in the partial ones because they do not entail the full majestic experience of the total eclipses (darkness descending, stars becoming visible, crickets chirping), and so I didn’t include them in my proceeding list.
Additionally, total solar eclipses in the world from 2019-2030:
The most easily accessible one to me is the 2024 eclipse that goes through the United States. However, I also would love to travel to New Zealand at some point in my life so perhaps the 2028 eclipse would be a perfect opportunity to go there.
Blog 0: An Introduction to Katie
Hello! My name is Katie. I am from Atlanta, GA and am excited for astronomy class this semester.
The Journey Begins
Thanks for joining me!
Good company in a journey makes the way seem shorter. — Izaak Walton
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