Big Bang Theory
What theory explains the universe's formation?
Big Bang Theory
Do low-mass or high-mass stars live longer?
low-mass
What is created from a nebula collapsing?
What will happen when a star becomes a red giant?
Expand and Cool
Does a lower mass (mouse) or greater mass (lion) have a stronger gravitational pull on the Earth?
The lion (greater mass)
Was the Big Bang an explosion or an outward expansion into space?
Outward expansion
What is the lightest element on the periodic table?
Hydrogen
Which star burns the hottest (white, yellow, red or blue)?
blue
What is on the y-axis of the H-R diagram?
luminosity
The strength of the gravitational force (increases or decreases) with distance between two objects
decreases
Cosmic microwave background radiation (CMBR) is radiations that is coming towards us from all directions. This leads us to believe CMBR is evidence for the Big Bang Theory. True or False?
True
What is a low-mass star that converts helium to carbon?
Red giant
A spiral galaxy is mostly older stars. True or False?
What is on the x-axis of H-R diagram?
Suppose an object is in orbit around the earth. The earth’s gravitational pull somehow becomes stronger than the object’s forward motion. What will happen to the object?
The object will fall towards Earth
What does it mean for light to be "redshifted"?
It means that its wave looks more like the waves at the red end of the electromagnetic spectrum. Its wave peaks are spread further apart, as opposed to closer together. This greater distance between peaks is due the expansion of space that began after the Big Bang.
How are heavy elements such as gold and iron formed in the universe?
Supernova Explosions
What is nuclear fusion? Hint: think hydrogen and helium
Stars create elements heavier than hydrogen.
What will happen at the end of the sun's life cycle?
As the star ages it will expand and cool some. It will get bigger until it becomes a red giant. Closer to the end of its life, it will become denser and contract and get smaller. It will burn white while it is a white dwarf and eventually become a small dark black dwarf.
A great amount of energy is needed to place an object in orbit around the earth. Why?
The object must be constantly trying to move forward at the same time that the earth's gravitational force is pulling it downward. This requires a lot of energy.
What are three points of evidence for the Big Bang Theory?
First, we observe that radiation coming toward earth is redshifted, and the older it is, the more redshifted it is. This indicates that the radiation has been moving through an expanding universe. As the universe expands, the waves of the radiation become farther apart--just like the waves on the line you drew on the balloon. Second, using highly advanced telescopes, scientists have observed that the distances between galaxies are increasing over time. This indicates that the universe is expanding, pushing galaxies farther and farther apart.
Third, radio telescopes detect cosmic microwave background radiation, which fills the entire background of space and appears to be left over from the initial Big Bang event. It is redshifted and cooler than what it would have been at the very beginning.
Define nucleosynthesis.
Nucleosynthesis is the formation of elements heavier than hydrogen through the process of nuclear fusion. In the first few minutes after the Big Bang, hydrogen nuclei fused to form helium atoms which then collided with other helium atoms or other protons to form lithium or beryllium. Right after the Big Bang, only hydrogen, helium, lithium, and beryllium were synthesized.
Name and describe two out of the three galaxies.
An elliptical galaxy is shaped like an elliptical, though the degree to which it has this shape may vary. Elliptical galaxies are made mostly of older stars; they are very enormous. Spiral galaxies have a spiral shape. The arms of the spirals usually contain bright, young stars. All other galaxy types are collectively called irregular galaxies. These have no specified shape.
Explain orbital motion.
Orbital motion develops when one object in forward motion approaches a second object. The second object’s gravitational pull on the first object is balanced by the forward motion of the first motion, and an orbit results.
Suppose there is a space ship in orbit around the Earth. We want to bring it out of orbit and back to Earth. What is one way to bring it out of orbit?
The space ship needs to slow down.