The Birth of Stars, and the Sun. Stars: Old Age, Death, and New Life
Galaxies and Our Home: The Milky Way
Dark Energy and the Expansion of the Universe
100
Which light has the longest wavelength?
Red
100
How many kilometers are there in a light year?
9.5*10^12 km
100
How old is our Sun?
5 billion years old
100
About how many stars are in our galaxy?
200 billion
100
Is dark energy an antigravity force?
No, it gets stronger with distance, opposite of gravity
200
What did Hubble used to study the lights?
Spectroscope
200
About how many galaxies are there in the universe?
About 100 billion galaxies, all of different sizes and shapes.
200
How are stars formed?
Stars are formed when nebulas collapse in on themselves. Small amounts of matter collide and stick together, becoming larger masses with increasingly stronger gravity. The increased gravity may be the trigger for a nebula to collapse. Another trigger could be the impact from a shock wave of gas and other matter from a supernova.
200
Barred spiral galaxies
Hubble named these SB galaxies ______
200
What percent of matter in the universe is visible?
What percent of matter in the universe is visible?0.4%
300
True or False? The greater the blue shift, the faster the galaxy is moving away, and the farther away it has to be.
False
300
What is the current best estimation for all the stars in all the galaxies of the universe? What is the current best estimation for the volume of the space?
1.0*10^22 stars and 1*10^30 cubic light years
300
Describe nuclear fusion.
The fusion of six hydrogen protons produces one helium nucleus with two protons and two neutrons. The reaction releases an enormous amount of energy in the form of heat, light, X rays, gamma rays, and energetic particles such as positrons and neutrinos, as well as two free protons.
300
Describe what star clusters are
Groups of stars that travel in space together and are held together by gravity
300
How fast is the universe expanding by volume?
1X10^12cubic light years a minute
400
What is the beginning point of the universe call? How old is the universe estimated to be?
Point Zero
13.7 billion years
400
What is difference of absolute magnitude and apparent magnitude.
Absolute magnitude is the actual amount of light the star gives off, recorded at a standard distance while apparent magnitude is the brightness of a star as it appears in the night sky.
400
List these stars in order of hottest to coolest: Red giant, Blue giant, Supergiant, Red dwarf, White dwarf
Blue giant, White dwarf, Supergiant, Red dwarf, Red giant
400
The largest black holes have up to how many solar masses?
tens of trillions
400
What problems did the oscillating theory run into?
It could not explain the gravitational force that held star and galaxy clusters together
500
Which two satellites provide evidence for the Big Bang?
Cosmic Background Explorer (COBE) and Wilkinson Microwave Anisotropy Probe (WMAP)
500
What are parallax and baseline?
Parallax is the apparent motion of a nearby star against the background of more distant non-moving stars. Baseline is an imaginary line from which the distance to an object is measured; the length of the baseline is known.
500
What is the solar luminosity of a black dwarf?
What is the solar luminosity of a black dwarf?0, black dwarf do not produce visible light
500
Why are the stars in Globular clusters usually small, under 2 solar masses?
They are mostly smaller stars because all the massive stars have either exploded as supernovae or have become white dwarfs
500
Explain the difference between dark matter and dark energy
Explain the difference between dark matter and dark energyDark matter is thought to be an unknown particle yet to be discovered and is responsible for the gravity that holds the galaxies together. Dark energy is thought to be a stabilizing force in the universe; based on the idea that there is energy in empty space