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50 Cards in this Set

  • Front
  • Back
What is a star
Object in space made of burning gasses which produce their own light and heat through nuclear function
What is Nuclear fusion
The process by which suns produce light and heat (2 hydrogen atoms combine to form 1 helium atom + energy)
What is the Hertzsprung-Russel diagram
charts classification of starts by temeprature and brighness (luminosity)
What colors on the Hertzsprun-Russel diagram mean hot and cold
Red- coldest
Blue- hottest
What is the life cycle of a star?
Main star (10 billion years)
Hydrogen runs out (Red giant)
Helium runs out (Planetary Nebula)
Core collapses (White dwarf)
Cools off (black dwaf)
What happens to huge starts?
Huge star (100-300 billion years) collapses supernova)
changes to nutron star/black hole
What kind of star is our sun
Yellow dwarf
Age of our sun
4.6 billion years
will last another 5 billion
type of star
main sequance star
medium sized star (large for a medium star), medium temperature, medium luminosity
92% Hydrogen, 8% Helium
What is the speed that the sun spins on its axis
Slowly (25 days)
What is the core
Middle of the sun
What is the temperature of the core
27,000,000˚F (very hot)
What is the convection and radiation zone
areas where heat produced in the core of the sun rises to the surface
What is the photosphere
outer surface of hte sun
What is the temepratrue of the photosphere
11,000˚F (coolest part of the sun)
What is the chromosphere
layer of atmosphere outsife the photosphere
What is the corona (other than beer)
outermost region of sun's atmosphere
What is the temperature of the corona
What are sunsport
cooler region of the photosphere caused by strong magnetiv fiends (storms)
What are solar flares?
a sudden eruption of hydrogen gas on the surface of the sun, usually associated with sunspots
What are solar prominences
an arc (loop) of gas that erupts fomr the surface of the sun
What is a galaxy?
a large group of stars, gas, and dust held together by gravity
How many types of major glaxies are there?
What is the elliptical galaxy?
some elliptical galaxies are nearly circular in shape, some elliptical galaxies are extremely stretched out, flattenedd, or elongated
What is a spiral galaxy?
galaxies with bright nuclei. also had "arms" spiraling out form the middle
What is a barred spiral
Tipically flat- to bars come out from the center and arms come off the bar
What is a regular spiral galaxy
when the arms come directly from the core
how many stars are in the milky way?
100 billion
What is an irregular galaxy
Galaxies that can't be classified as either spiral or elliptical
what is one of the most known theory on the origin of the universt
Big bang theory
What is the big bang theory
billions of years ago trememdous primeval explosion started expansion of universe from single point (today the radiation survives as microwaves (not like the ones in your kitchen))
What is some evidence of the big bang theory
1916- Einsteins' theory of relativity- reinvented thoughts about gravity and matter
Cosmological principle- universe appears the same in all directions; homogemeous
Noticed Doppler red shift between nebulae
1929-Edwin Hubble stated that galaxies spreaded apart uniformally in every direction as th universe expands uniformally in all directions (speed of expansion is proportional to distance asay, means that it has taken every galaxy the same amount of time to move from a common starting position to its current position)
1964- discovery of cosmic backgrounf radioactive energy (microwaves) from far reaches of universe- strongest evidence of big bang (evergy and every's temperature are uniform)
Who and when was the first person to propose this theory
1927- Belgian priest George Lemaitre first to propose that the universe began with the explosion of a peimeval atom
What is a meteoroid?
chunks of rock 9not as bug as asteroids) floating around IN SPACE (most meteroids are parts of passing comets)
What are meteors?
"shooting stars"- a meteoroid that enteres the EARTHS ATMOSPHERE
What are meteorites
- a meteor that does not completely burn and STRIKES A PLANET
What are asteroids
a piece of rock smaller to but smaller than a planet orbiting the sun
What is the difference between meteorids anr asteroids?
Asteroids are larger than meteoroids (larges is ceres 620-mi)
Meteors do not orbit the sun
What is the asteroid belt
Most asteroids orbit the sun in this region dounf between mars and jupiter
What is the shape of asteroids
irregular- not round
What is a comet
a mass of rock and dust mixed with frozen water, and gasses ("dirty snowballs")
What is the structure of the comet
HEAD-Nucleus: solid center of comet- Coma: gas cloud surrounding comet
TAIL-trail of gasses begind comet-formed by solar wind: only present close to sun- always points AWAY from the sun
What is the origin of comets
Kuiper belt (30-50 AU's)- short period comets (200 years)
Oory clout (100 AU's)- long period comets
What are main sequence stars
Hottest and largest- generate most light
Giants and supergiants-
Bright but not hot
White dwarfs
Hot but not bright
Good job
Your almost donw!