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29 Cards in this Set
- Front
- Back
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What is a novae
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sudden unexpected brightening of a star
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supernova
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happens just once to a star, afterwards, there is no more star
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when a star dies they become:
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) White dwarf, eventually becoming a black dwarf (after a VERY long time).
2) Neutron Star, and possibly a pulsar if it is spinning and taking in material. 3) Black Hole |
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What is a helium blast
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When a star finishes burning through its hydrogen, it contracts and then the helium ignites
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causes of novas (4)
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1) Interaction between two binary stars-
2) helium flash 3) Planetary Nebula- 4) CME-Corona Mass Eruptions-For |
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what is a Planetary Nebula-
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As a small to medium star goes from a red giant to a white dwarf, it often expels a large part of gas in a ring around itself as it shrinks. This also causes a change in brightness
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what is a CME or a Corona Mass Eruptions
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a star will suddenly have a massive eruption of a huge solar flare, this causes a temporary brightness change if it lasts long enough
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CHANDRASEKHAR LIMIT
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states that a white dwarf which has mass greater than 1.4 times that of Sun cannot exist
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Chandrasekhar limit will not allow the electrons of an atom to do what.
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to shrink any further into the atom, Thus the star cannot shrink anymore and is doomed to slowly cool off.
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why are black dwarfs really one giant diamond
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carbon is the last element made . diamonds are compressed carbon
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what are white dwarfs
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once were Stars with stellar masses less than 1.4 solar masses
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what is “Roche Lobe”
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region of space around a star
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what happens when binary star expands past “Roche Lobe”
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shares material with sister star
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how does sharing of material effect binary planets
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giving star slows down its evolution; receiving star speeds up its evolution
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What is a neutron star
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small, incredibly dense remains of giant stars, usually class A or B which have exceeded the Chandrasekhar limit
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why are there only neutrons in a Neutron star
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gravity so strong it overpowers electrons and forces them into protons ...this leaves only neutrons. The nucleus no longer exist
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Typical size of neutron star
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size of city of Manhatten
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Typical mass of neutron star
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mass is less than 3 solar masses
: usually between 3 and 1.4 solar masses |
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density of neutron star
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Density is incredible, “that of thimble stuffed with over a billion automobiles”,
*10 times that of a white dwarf |
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what is a pulsar
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neutron star which is spinning and is in-taking material
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As pulsars take in new aterial what happens
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pulses like a lighthouse beam...hense "pulsar"
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what are these pulsing beams of a pulsar
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energetic electromagnetic radiation
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Two types of black holes
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stellar and super-massive
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What is a Stellar Black Hole
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type of Neutron star:very large star which went super-nova and whose remains after-wards not only exceed the Chandrasekhar limit, their electrons are pulled by gravity into the protons, and THEN the very neutrons are pulled in on top and into themselve
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What is SINGULARITY
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As the star’s mass collapse, it reaches a point of infinite density and zero radius
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What is SCHWARZCHILD RADIUS
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radius around the singularity where light cannot escape is a function of its mass
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another name for SCHWARZCHILD RADIUS
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event horizon
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where are Supermassive Black Holes found
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center of every galaxy
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are black holes "holes"
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incredibly dense matter like nothing else
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