Astronomy 1010 Midterm – Flashcards
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Lookback-time
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The idea that the more distant an object is, the longer the light from that object takes to reach us. Therefore looking at back in time.
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Protostar
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The Contracting mass of gas that represents the young stage of a star formation.
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The Strong-Force
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Is the force that keeps ordinary matter together. binds neutrons and protons and also quarks.
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Absolute Visual Magnitude
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The Intrinsic brightness of an object at a range of 10 parsecs
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HR-Diagram
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the Herzsprung-Russell Diagram is a visual representation of stars, graphed from Lumosity Vs temperature or Spectral Classification.
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Proton
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Positively charged subatomic particle
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Population 1 star
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A metal-rich young star, consisting mostly of chemicals heavier that Helium.
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Density
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The compactness of matter within a certain volume
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Yellow Giant
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high Lumosity star with a relatively low Temperature or spectral class
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Chromosphere
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the reddish gasseous outer layer of a star
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Fluctuation
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is a departure from the average value that happens spontaneously
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Force
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Any push or pull; made up of all 4 fundamental forces
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Energy
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a number that represents how much work can be done
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Hydrogen
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Atom made of 1 proton and 1 electron
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Deuterium
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A Hydrogen atom that holds a Neutron in its nucleus.
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Helium
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Atom made of 2 protons, 2 neurons and 2 electrons
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Elementary Particle
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a particle that cannot be divided further, used as building blocks. Ex: Quarks, Protons, Electrons
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Temperature
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The measure of Kinetic Energy an object has
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Heat
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The transfer of energy from one place to another, or Object to another
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Light-Year
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The measure of distance a Light travels in a year. 5.88 Trillion Miles
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Photon
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The Elementary Particle of light
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MegaParsec
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Mpc; a unit that is equal to 3.26 million Light Years
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Galaxy
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Conglomeration of Stars, Gas and dust that are gravitational ly bound together
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Metal
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An element that is heavier that Helium
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Population 2 stars
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These are Metal-poor young stars that consist of almost entirely helium and hydrogen.
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Supernova
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A violent explosion death of a star.
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Astronomical Unit
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AU; The average distance from the Sun to the Earth
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Nebula
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A fuzzy object of undetermined size
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Accretion
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the process of which small objects combine to make larger objects.
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Condensation Sequence
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The order in which chemical compounds transition from a gas into a solid state.
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Volatile Materials
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Gaseous and Icy materials that can easily evaporate at high temperatures
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Refractory Material
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Solid materials that can withstand high temperatures
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Star
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A ball of Plasma that performs nuclear fusion at the center to convert matter into energy
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Planetesimal
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Refers to a large chunck of rock that is the building block of a planet
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protoplanet
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Refers to a planet that is still growing
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Inner Solar System
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Is the region from the sun to the Asteroid Belt
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Outer Solar System
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Is the region from the Asteroid Belt and beyond
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Black Hole
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The corpse of a dead star. It has gravity so strong that light cannot even escape it
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Herzsprung-Russell Diagram
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this HR-Diagram is used to graph celestial bodies by lumosity vs spectral catagory or temperature
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Neutron Star
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A corpse left by a massive star consisting of neutrons that form when the star ran out of fuel
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Main Sequence
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This is a part of the Herzsprung-Russell Diagram in which most hydrogen fusing stars are located
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Nuclear Fusion
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Is the process in which two smaller nuclei are fused together to form larger nucleus, releasing energy in the process
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Planetary Nebula
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Rings or strings of material seen fleeing away from a white dwarf. consists of outer layers of stars in their giant phases.
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Red Giant
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Low Mass to Medium mass star with to size of 50-100 Solar Radii. High Lumosity but low temperature
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SuperGiant
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an expanding dying star that is over 8 solar masses with a size of 100-1000 solar Radii. Medium temperature, high Lumosity and mass
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White Dwarf
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Corpse left by a low-medium mass star after it runs out of helium. High temperature, low lumosity and mass
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Apparent visual magnitude (mV)
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the brightness of the visible wavelength
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Absolute Visual Magnitude (MV)
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the brightness of the visible wavelength if it was 10 parsecs away.
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Angstrom (A)
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unit of length which equals 1 ten billionth of a meter (0.1 nanometer)
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CCD
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Charge Coupled Device; Used by digital cameras and to measure brightness, these devices turns light into an accumulation of charges.
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Flux
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Measure of flow of energy through a surface
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Lumosity
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The total amount of energy a star radiates in 1 second
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Stellar Parallex
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Shift of position of nearby stars relative to the rotation of the earth.
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5 reasons to be confident in the formation of the universe?
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1: Cosmic Microwave Background (CMB) 2: Temperature & Density Fluctuation 3: Olbers Paradox (Light Paradox) 4: Hubbles Law (Expansion of Universe) 5: The Cosmological Principle (Homo Principle)
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Cosmic Microwave Background (CMB)
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The observed CMB radiation from the early universe was very hot and dense. today it is more distributed and spread out.
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Temperature & Density Fluctuations
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There are temperature and density fluctuations in the CMB that would grow into galaxies after billions of years.
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Olbers Paradox
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States that Hypothetically The whole sky should be covered in stars due to the idea of an infinitely expanding of the universe.
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Hubbles Law
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This law states that the Universe is expanding and was found by the observation of galaxies moving away from each other. This is due to the growth of the space between.
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The Cosmological Principle
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States that the universe must be identical in all regions and directions
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Hubbles Tuning fork
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This was hubbles way of classifying Galaxies. He believed that there was an evolution of elliptical galaxies to spiral or spiral bar. Even though the evolution theory wasn't correct, his classification system is still used today.
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Solar System formation
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a nearby supernova starts a reaction to collapse a cloud of Gas and Dust. Takes around 4.5 billion years & 500,000 years for planets to form
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Galaxy Formation
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Occurred after the big bang by collapsing dust and gas clouds but mostly only change now due to interactions with other galaxies. The oldest known galaxy is 13 billion years old.
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Reason why Gas Giants are larger than terrestrial planets
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Solar winds swept most of the materials out of the inner solar system.
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Reason why Gas Giants are larger than terrestrial planets
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The sun Swallowed up most of the resources of the inner solar system due to accretion
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Reason why Gas Giants are larger than terrestrial planets
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It is easier for these planets to hold on to lighter gasses since the temperature is much lower
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Geocentric theory
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that the earth is the center of the universe and all celestial bodies rotate around it
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4 fundamental forces
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1: The Strong Force 2: The Weak Force 3: Gravitational Force 4: Electromagnetic Force
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The Strong Force
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Bind elementary particles together such as quarks
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The Weak Force
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The force of things falling apart or decaying
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Gravitational force
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The force of attraction created by anything with mass
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Electromagnetic Force
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The force of interaction between electrically charged particles
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Step 1 of star life-cycle
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Nebula of dust and gas collapses due to nearby supernova. Starts spinning and begins accretion of materials to the center for 100,000 years where eventually it gets hot enough to start performing nuclear fusion.
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Step 2 of star life-cycle
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The force of gravity continues to pull materials inward while nuclear fusion pushes everything out. This continues to burn up the hydrogen in its core and gains temperature.
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Step 3 of star life-cycle
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The Hydrogen in the star eventually runs out and therefore creates no more fusion to push out the layers. It becomes unstable and collapses under its own weight.
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Step 4 of star life-cycle
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the core gets hotter and denser while the other layers of the sun grow and expand until the star enters its red giant phase
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Step 5 of star life-cycle
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during the red giant phase there is increased pressure in the core allows the sun to fuse heavier nuclei such as helium and carbon.
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Step 6 of star life-cycle
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when all the helium is used the core stabalizes and all the other layers blast off and it becomes a white dwarf and continues to cool over time.
