Stars 1
These objects make their own light in space.
What are stars?
This diagram helps scientists compare stars by their temperature and luminosity.
What is the Hertzsprung-Russell (H-R) diagram?
Stars are born in these giant clouds of gas and dust.
What is a nebula?
This is the part of the Milky Way where our solar system is located.
What is the Orion Arm?
This theory states that the universe began as a single point and has been expanding ever since.
What is the Big Bang Theory?
The color shift observed when a galaxy moves away from Earth.
What is redshift?
Stars shine because of this powerful process.
What is nuclear fusion?
On the H-R diagram, the y-axis shows this.
What is luminosity?
When a small or medium star runs out of fuel, it becomes this type of star.
What is a red giant?
Groups of galaxies bound together by gravity are called this.
What are galaxy clusters?
Radiation is the leftover energy from the Big Bang.
What is Cosmic Background Radiation?
These are the most abundant elements formed in the early universe.
What are hydrogen and helium?
This determines temperature and luminosity.
What is mass?
A white dwarf is left behind when a lower-mass star sheds its outer layers, creating one of these glowing clouds of gas.
What is a planetary nebula?
The most massive stars collapse into this object.
What is a black hole?
This type of galaxy has arms that extend from a central disk.
What is a spiral galaxy?
This cannot be seen but is detected by its gravitational effects.
What is dark matter?
Before the Big Bang theory, this now-rejected theory proposed that new matter is continuously created as the universe expands.
What is Steady State Theory?
What is white dwarf?
A supernova occurs when a massive star’s core collapses after forming too much of this element.
What is iron?
Stage of a star's life cycle where hydrogen is fused into helium.
What is main sequence?
This galaxy type lacks a defined structure and often results from gravitational interactions with nearby galaxies.
What is an irregular galaxy?
This extension to the Big Bang Theory proposes that the universe underwent an extremely rapid expansion in its earliest moments before slowing down.
What is Inflation Theory?
Includes hydrogen, helium, and heavier elements, makes up this approximate percentage of the universe.
What is ordinary matter?
These stars have more gravity pulling inward, cores with higher temperatures, and produce and use more energy through fusion.
What are high-mass stars?
In a stable star, the inward pull of gravity is balanced by the outward push of this force.
What is pressure from fusion?
Stage of a star's life cycle where gas and dust contract under gravity.
What is protostar?
This type of galaxy, characterized by a smooth, featureless shape, contains mostly old stars and little gas or dust.
What is an elliptical galaxy?
These areas in the cosmic microwave background radiation map are brighter than average, indicating slightly more matter than in other regions.
What are hot spots?
As the universe expanded and cooled, the cosmic background radiation shifted into this part of the electromagnetic spectrum.
What is microwave?