Q: How are galaxies classified?
Q: What tool has helped astronomers understand a lot about galaxies?
Q: Name three characteristics of spiral galaxies.
Q: Name two characteristics of barred galaxies.
Q: Name three characteristics of elliptical galaxies.
Q: Name two characteristics of lenticular galaxies.
Q: What kind of star cluster is a group of older stars, looks like a ball, and contains up to one million stars?
A: By their shape.
A: The Hubble Space Telescope
Have a bulge at the center
Have spiral arms
Arms made up of gas, dust, and new stars
Examples: Andromeda and our Milky Way Galaxy
Much like spiral galaxies
Have two distinct “bars” vs. many spiral arms
About 1/3rd of all galaxies
Simply a massive blob of stars
Spherical or more stretched out
Very bright centers with little extra gas and dust
Contain mostly old stars
Has both a bulge and a disk
All the stars are thought to be old
Have no spiral arms
There is little or no gas
A: Globular Cluster
Q: Name three characteristics of irregular galaxies.
Q: Galaxies are composed of what four things?
Q: What is a large cloud of dust and gas in interstellar space where stars are born or where stars explode at the end of their lives?
Q: What kind of star cluster is a group of stars that are close together relative to surrounding stars? Example: The Pleiades
Q: What is star-like, very luminous, generates a lot of energy, and is very far away (6 billion light years)
Q: Which is closest to Earth?
1)the moon
2)the sun
3)other planets in our Solar System
Q: Distances are so great in space that a new unit was created. What is it called and how long is this unit?
Don’t tend to fit into any other class
Irregular shape
No center bulge
May have been formed by the collision of two or more galaxies
Many are close in proximity to large spiral galaxies. Perhaps the spiral galaxies are distorting the shape of irregular galaxies.
Billions of stars
Some planetary systems
Gas clouds
Star clusters
A: A nebula
A: Open Star Cluster
A: A quasar
A: The moon
A: The Light Year
6 Trillion miles/year
Q: How fast does light travel?
Q: What is the closest star to Earth other than the sun?
Q: What is the closest star to Earth other than the sun that we can see from the northern hemisphere?
Q: “Star A” and “Star B” are the same size, brightness, and distance from Earth.
When looking at these stars from Earth, which star will appear to be brighter?
Q: “Star A” and “Star B” are the same size and brightness.“Star A”, however, is much farther away from Earth than “Star B”.
When looking at these stars from Earth, which star will appear to be brighter?
Q: True or False?
Stars undergo a life cycle.
A: 186,000 miles/sec
A: The closest star to Earth (other than our sun) is Proxima Centauri; it is 4.3 light years (26 trillion miles) away
From Ohio, we cannot see Proxima Centauri. It can only be seen from the southern hemisphere.
The brightest star in the northern hemisphere (other than our sun) is Sirius.
Sirius is referred to as the “dog star” because it is in the constellation Canis Major (big dog).
It is 8.6 light years away from Earth.
A: They will appear to be the same brightness
A: “Star B” will appear brighter just because it is closer to Earth.
A: True
Q: True or False?
The stages of the life of a star generally follow a pattern and are fairly regular.
Q: “Star C” is very big and bright.
“Star D” is not so big or bright.
How could these two very different stars seem to be the same brightness from Earth?
Q: Fill in the blank:
Stars begin their lives as clouds of dust and gas called ______.
Q: What does the following describe?
Gives off no visible light
Must undergo many changes before it is recognized as a star.
It continues to contracts over a period of millions of years
Shrinkage causes an increase in pressure and temperature
Q: What is nuclear fusion?
Q: A star spends most of its life as a ______, which is a stable condition.
Q: Fill in the blanks:
Very _____ stars burn their fuel much ______than smaller stars. Their main sequence may last only a few hundred thousand years.
A: True
A: “Star C” is much farther away from Earth, thus, it seems as though it is the same brightness, or magnitude, as
“Star D”.
A: Nebula
A: A protostar
Hydrogen + Hydrogen = Helium + a lot of energy!
A: Main sequence star
A: Large, faster
Q: Fill in the blanks:
______stars will live on for billions of years because they burn their fuel much more ______than large stars.
Q: Fill in the blanks:
At the end of an average star’s life, it will expand into what is known as a ______.
Massive stars will become ______at the end of their lives.
Q: Fill in the blanks:
Most average stars will blow away their outer atmospheres to form a ______.
Their cores remain behind and burn as a ______until they cool down. What is left is a dark ball of matter known as a ______.
Q: What is a supernova?
Q: How long does a supernova shine?
Q: How bright is a supernova?
Q: At the end of their lives depending upon how large they were to begin with, massive stars will either become a ____ or a _____.
Q: List the life stages, in order, of an average star. (Hint: There are seven stages.)
A: Small, slowly
A: red giant, red supergiants
A: Planetary nebula, white dwarf, black dwarf
A: If the star is massive enough, the collapse of the star will trigger a violent explosion known as a supernova.
A: Supernovas are very bright and can cause a brief (few months) burst of radiation that can outshine an entire galaxy.
A: During this explosion, a supernova can give off as much energy as our Sun could emit over its life span!
A: Neutron star or a black hole
A: Stellar nebula, protostar, main sequence star, red giant, planetary nebula, white dwarf, black dwarf
Q: List the life stages, in order, of a massive star. (Hint: There are six stages.)
Q: What does the color of a star depend on?
Q: What can a scientist learn about a star from its spectrum?
Q: What color are the hottest stars? Red, yellow, orange, green, purple, or blue?
Q:The H-R diagram shows the relationship of a star’s _____ and its _____.
Q; Name five types of galaxies.
Q: Where are globular clusters found?
Q: Where are open star clusters found?
Q: Why do scientists study galaxies?
Q: What does a star’s color indicate?
Q: What kind of galaxy is the Milky Way galaxy?
A: Stellar nebula, protostar, massive star, red supergiant, super nova, neutron star or a black hole
A: Temperature
A: Its composition (what it is made of) and its temperature
A: Blue
A: Surface temperature and absolute magnitude
A: Spiral, barred, elliptical, lenticular, and irregular
A: In the spherical halo of spiral galaxies and near elliptical galaxies
A: Along the spiral disk of galaxies
A: To learn what early galaxies looked like, and to learn how our galaxy was formed
A: Its temperature
A: Probably a spiral galaxy
Q: Which is the largest, a galaxy, a neutron star, or a nebula?
Q: Which of the following magnitudes indicates the brightest star? 5, -10, or 0
Q: What kind of star sends out rapid beams of radiation? They spin very quickly.
A: A galaxy
A: -10
A: pulsars