Honors Astronomy and Literature final
Galaxy
A galaxy is a gravitationally bound system of stars, stellar remnants, interstellar gas, dust, and dark matter. The word is derived from the Greek galaxias, literally 'milky', a reference to the Milky Way galaxy that contains the Solar System
What was the form of the material from which the solar system formed?
A nebula made mostly of hydrogen and helium gas, but enriched in heavier elements from supernova explosions
What is a singularity?
A point of infinite density
Donegality
A term to describe a story's unique essence or atmosphere. Ward boldly gives the word "donegality" a new metonymic meaning: not now the flavour of Donegal itself, but the idea of a particular flavour, atmosphere or mood, imparted to or expressed through a story. you keep going back to stories because of how they make you feel rather than just the words. Donegal is a town in Ireland that has a specific/special/peculiar feeling that is different than the feeling of London which has its own distinctive feel. Books have unique feelings for you specifically and you go to them when you feel a certain way
An ideal blackbody in astronomy is an object that
Absorbs all electromagnetic radiation and emits electromagnetic radiation at all wavelengths
What type of spectrum do we observe from all stars?
Absorption spectrum
The expansion of the universe means that
As time goes by, space itself expands carrying the galaxies along with it
If the Sun were replaced by a 1-solar mass black hole, then Earth would
Continue to orbit the black hole in precisely its present orbit
Filaments and voids
Cosmic voids are vast spaces between filaments (the largest-scale structures in the universe), which contain very few or no galaxies In cosmology, galaxy filaments are the largest known structures in the universe, consisting of walls of gravitationally bound galaxy superclusters. These massive, thread-like formations can reach 80 megaparsecs h⁻¹ and form the boundaries between large voids.
The fact that each type of atom has a unique pattern of electron orbits helps explain why
Each type of atoms shows different absorption or emission spectra
The event that eventually settled the Shapley-Curtis debate about "spiral nebulae" was
Edwin Hubble measuring the distance to the Andromeda galaxy
Most of the elements beyond H and He in the periodic table that we see in our Sun and in the planets of the solar system probably originated
From fusion reactions in the centers of earlier stars that have since died
Dark matter cannot be seen, but we can detect its presence by its
Gravitational influence on visible stars
Space-Time
In physics, spacetime is any mathematical model which fuses the three dimensions of space and the one dimension of time into a single four-dimensional manifold. Spacetime diagrams can be used to visualize relativistic effects, such as why different observers perceive differently where and when events occur
How does a period of extremely fast inflation very early in the history of the universe explain the observation that the geometry of the universe looks flat (not curved) to us?
Inflation increased the size of the universe so much that the resulting universe looks flat from any point of view
Recent results from very bright supernovae in very distant galaxies seem to indicate that the expansion of the universe
Is accelerating (speeding up)
What happens to the light that is missing in an absorption spectrum?
It is absorbed by atoms in a cool, low density cloud
Our Galaxy is
One member of a small group of galaxies
Singularity (astronomy)
Only one in our universe that has all the energy and matter that is ever going to be in the universe. Black hole singularities are different. We could call this the white singularity that grew to create the universe. A point that is infinitely dense but not infinitely massive. Squeeze it all into something that has no radius. Finite mass infinitely high density because density = m/v. We don't know why expansion started. Lots of theories but no idea. We say it was God.
The discovery of thousands of exoplanets has forced astronomers to
Revise theories of how planetary systems, including our own, have been formed
Around 1801, Thomas Young in England showed that light behaves as a wave by
Shining light through two closely spaced slits and observing the resulting pattern of light on a distant screen
According to general relativity, why does Earth orbit the Sun?
Space around the Sun is curved and Earth follows this curved space
We can tell that the Sun rotates at different rates at different latitudes because of the
Sunspots
The spectral type of a star is most directly related to (and uniquely determined by) its
Surface Temperature
Cosmic Microwave Background Radiation (CMB)
The Cosmic Microwave Background radiation, or CMB for short, is a faint glow of light that fills the universe, falling on Earth from every direction with nearly uniform intensity.Cosmic background radiation is electromagnetic radiation from the Big Bang. The origin of this radiation depends on the region of the spectrum that is observed.
Some scientists speculate that our universe is not the only universe that exists, but the only one we can gather evidence about. This idea is called
The Multiverse Theory
Scientists speculate that the properties (laws) of the universe must be the way they are because if they were significantly different, we would not be here to think about them. The ideas is called
The anthropic principle
According to the most recent data from satellites making precise measurements of the properties of the cosmic microwave background radiation (CMB)
The dark energy makes up just a little less than 70% of the density of the universe, making it the most significant constituent of the mass-energy
The discovery that the Sun and similar stars are about 25% helium by mass posed a dilemma: there was too much helium in the universe to be accounted for by nucleosynthesis in stars in the contemporary cosmological models. How was this dilemma resolved?
The early universe was found to be hot and dense enough to produce helium from hydrogen, even before the first stars formed
When they talk about the Copernican principle, philosophers and astronomers mean that
The idea that there is nothing special about our place in the universe
When the absorption spectrum of light from distant galaxies is measured, what is found?
The lines in the absorption spectrum are shifted towards the red end of the spectrum, with light from the most distant galaxies being shifted by the largest amount
At an age of 380,000 years, the temperature of the universe had fallen to 3000 K, and electrons could then combine with protons to produce hydrogen gas instead of roaming freely through space. What major transition occurred as a consequence of this change in the universe at this time?
The universe became transparent to light for the first time
Hubble's observation that galaxies farther away from us are moving faster implies
The universe is expanding
How are galaxies spread throughout the universe?
They are grouped into clusters that in turn are grouped into clusters of clusters (superclusters)
In discussing galaxies and the universe, astronomers often talk about "voids". Wat are voids?
Volumes of space hundreds of millions of light years across that contain almost no galaxies
Why did Einstein introduce the cosmological constant into the equations of his General Theory of Relativity when describing the universe?
Why did Einstein introduce the cosmological constant into the equations of his General Theory of Relativity when describing the universe?
Imagine that you observe a red nebula of hot, low-density hydrogen gas moving toward the Earth. Which of the choices best completes the following statement describing the spectrum of this nebula?
You would observe an emission spectrum that is blueshifted compared to a nebula that is not moving
Allegory
a story, poem, or picture that can be interpreted to reveal a hidden meaning, typically a moral or political one. Story with an extended metaphor—every part of the story is representative of something else like the everyman play (everyman= every one of us) author has a specific idea of what is should represent; rigid allegory= everything exactly lines up with a moral or metaphor, looser allegory= contains elements that remind you of something metaphorical but doesn't necessarily line up adds to understanding though
Blackbody
any light that you see is a true measure of its energy output and temperature, peak in the spectrum shows the strength of the stars energy something in the universe that absorbs all light. Does not reflect light but does emit light. Closest thing we have is a star. The light we see is a true measure of energy output. Red stars peak at a much lower temperature. For people you would have to use an infrared thing to see what they are outputting
Nebulae
any of the various tenuous (having little mass) clouds of gas and dust that occur in interstellar space.
Parable
can come up with simple moral but we mine for deeper meaning or more messages. Can also be appreciated as just a story
Electromagnetic Spectrum:
electromagnetic spectrum, the entire distribution of electromagnetic radiation according to frequency or wavelength. Although all electromagnetic waves travel at the speed of light in a vacuum, they do so at a wide range of frequencies, wavelengths, and photon energies.
invisible stories
from video with Oakrey. He writes a lot of magical realism. He likes invisible stories more than visible stories because a story is something more than a beginning, middle, and end. It is creating a feeling, mood, experience. Things that happen and they're created out of a plot but separate from the plot the idea behind magical realism, a story is atmospheric- creating a mood, if you can finish a book and simultaneously not finish it, create an experience, take the reader somewhere (ben okri) created out of a plot but separate from it
Hubble Flow
galaxies far away are moving away faster- when we look at galaxies they are all red shifted- all moving away; can measure velocity using that redshift—straight linear positive relationship- expansion of the fabric of space
Dark Matter
has mass and therefore curves space with gravity, can be described using newtons laws looking at galaxy clusters and realizes that they fly so fast they should be flying apart. Should be 5x more matter than we can see. As she measures velocities from doppler shifts using newtons laws she calculates mass and it's 9x more mass that must be interior than what she sees. Has mass to it, gravity, creates curvature to space but we don't know what it is. 85-90% of universe is dark matter. Doesn't interact with matter well. Has mass w gravitational force. Can be described using newtons laws
Multiverse
it is so statistically improbable that we exist that there must be other universes that exist similar to ours but slightly different, tied into the anthropic principle
Central Doctrine of Science
laws of nature always have to be the same (ex: gravity on earth is the same law as the one that governs Neptune), when things defy that law we look for explanations: are we missing something like dark matter? the belief that nature is lawful, and that those laws hold true everywhere and all the time
Wave-Particle Duality
light is wave or particle? Newton=particle, young=wave; light has those characteristics (wavelength, frequency, amplitude) Einstein says: it's both, photoelectric effect, light and matter has properties of both waves and particles. It depends how you measure it. Doppler shift is because it's a wave. Spectral shift is because it's a particle
Ramandu
literal living star He appears as an old man with a silver beard that comes down to his bare feet, dressed in a robe that appears to be made "from the fleece of silver sheep". Once a star, he grew too old and descended to the island at the beginning of the end of the world where he lived for some time with his unnamed daughter (of uncertain parentage, but later the wife of Caspian X and Queen of Narnia). Each morning they would emerge from their home to sing a song during the length of dawn, perhaps causing the sun to rise. Then, a mass of white birds would fly out from "the valleys of the sun" and settle all over the island. One bird would carry a fire-berry, which it would place in Ramandu's mouth. Each time Ramandu ate a fire-berry he would grow younger, until he was an infant, when he was to become a star again.
Eustace
main dragonish character
kappa (as in, "the kappa element in story")
means "mystery" hidden meaning. It's not obvious but it's very important. If CS Lewis had been obvious about planetary symbolism it may have distracted from the Christian symbolism. It's not preachy, it's a mystery element that gives you a feeling after reading something that you should change Stories are most valuable for their quality or atmosphere, not simply their plot. Stories must be series of events: but it must be understood that this series—the plot, as we call it—is only really a net whereby to catch something else. The real theme may be, and perhaps usually is, something that has no sequence in it, something other than a process and much more like a state or a quality. Stories earn our allegiance, Lewis argues, by conveying a distinct and coherent qualitative atmosphere
Lucy
opposite counterpart of Eustace
Which of the following rankings is correct for the size (width) of the following objects from smallest to largest?
planet, star, solar system, galaxy, universe
Fable
short story, typically with animals as characters, conveying a moral. Simplest ones
the music of the spheres
the influence the planets have on humans on earth-how they are connected to the planets. Kind of like the light of Christ. If it were to go away things would feel kind of awful but we don't recognize it
the Seven Heavens
the planets, pre-copernican: moon, mercury, venus, sun, mars, Jupiter, Saturn> used as the blueprint for the Narnian series, medieval idea- associations with each, influence etc kinda astrologyish different regions of heaven controlled by different planets. It's a medieval cosmological concept that was popular for a few centuries. Big idea in the Narnia Code. It was subtle in the Chronicles of Narnia. CS Lewis was a scholar of this era so he put it in there knowing most people would probably not recognize it
HR-Diagram
the plot of the stars--luminosity vs temperature. Astronomers started plotting luminosity and temperature of stars. Different kinds of stars fall in different places. Lots of patterns emerged and physics answered these questions. Supergiants are fusing larger elements like carbon, oxygen, neon diagram of stars with plotted luminosity vs temperature, showed trends in the distribution of different types of stars
Copernican Principle
the principle that the Earth does not rest in a privileged or special physical position in the universe. Specifically, it derives from the claim of Nicolaus Copernicus that the Earth was not stationary, when he proposed the heliocentric model of the solar system/basically were not special
Dark Energy
the push that broke up the singularity, kinda like anti-gravity, universe is speeding up- how we discovered dark energy exists (it should be slowing down) a force, maybe radiation, a push. Probably the same push that started the creation of the universe; it hasn't stopped. Dark matter holds things together. Dark energy discovered abt 20 years ago because universe is accelerating with some kind of antigravity pushing things apart. Should be slowing down. Also called cosmological constant. It is a push not a pull like gravity. Drives expansion.
Solar Nebula Hypothesis
the solar nebular hypothesis describes the formation of our solar system from a nebula cloud made from a collection of dust and gas. It is believed that the sun, planets, moons, and asteroids were formed around the same time around 4.5 billion years ago from a nebula. (spinning disk- why orbitals are mostly flat)
Anthropic Principle
weak and strong—right conditions have to exist bc if they didn't we wouldn't be here to see them, or: divine design:: either someone designed everything or there are multiple versions of our universe and this is just the only one we see
singularity (literature: Attridge)
what makes particular texts unique, the individual reader and their background and influences makes the experience more singular, more particular; each reading experience is something that has never existed in such a way before and never will, transcendent experiences that are impossible to re-experience beyond uniqueness, you have the reader and all their experiences and what they are going through at the moment. That reading experience is unique and has never existed before and never will again. Innumerable. Infinite texts and infinite people and infinite moments so many singular experiences