Star Birth
This is a large cloud of gas and dust in space where stars can form.
What is a nebula?
Stars shine because they release this.
What is energy?
In a star, gravity pulls in this direction.
What is inward?
This color star is usually hotter: red or blue.
What is blue?
Scientists study this from stars to learn about temperature, color, brightness, and composition.
What is light?
A giant cloud of gas and dust begins collapsing under gravity. As it collapses, the center gets hotter and denser, but it is not officially a main-sequence star until this specific process begins in its core.
What is hydrogen fusion? (nuclear fusion)
This force pulls gas and dust together during star formation.
What is gravity?
Nuclear fusion happens in this part of a star.
What is the core?
Pressure from hot gas and fusion pushes in this direction.
What is outward?
This color star is usually cooler: red or blue.
What is red?
This is a simplified representation of a real object, system, or process.
What is a model?
Before a star can begin stable hydrogen fusion, gravity must squeeze the protostar until the core reaches roughly this extremely high temperature.
What is about 10 million degrees Celsius?
This is a young forming star that has not fully become a stable star yet.
What is a protostar?
In stars like the Sun, hydrogen atoms fuse together to form this element.
What is helium?
A stable star exists because gravity and pressure are in this state.
What is balance?
More massive main sequence stars are usually much brighter and have this kind of lifetime.
What is shorter?
This is one limitation of classroom models of stars.
What is they leave out details / they are not perfectly to scale / they simplify reality?
Put these star-formation stages in the correct order:
main-sequence star, nebula, protostar
What is nebula → protostar → main-sequence star?
As a gas cloud collapses, the center becomes hotter and this.
What is denser?
Fusion needs extremely high temperature and this.
What is pressure?
or
What is density?
If gravity becomes stronger than outward pressure, a star or cloud may do this.
What is collapse?
This property is sometimes called a star’s “destiny maker.”
What is mass?
In a simulation, a value that students can change, such as mass or distance, is called this.
What is a parameter?
A collapsing cloud forms an object with too much mass to be a planet, but not enough mass to sustain hydrogen fusion in its core. This type of object is often called a “failed star.”
What is a brown dwarf?
A protostar becomes a true star when this process begins in its core.
What is nuclear fusion?
This is the difference between ordinary fire and the way stars shine.
What is ordinary fire is a chemical reaction, but stars shine through nuclear fusion?
This phrase describes the balance between inward gravity and outward pressure in a stable star.
What is hydrostatic equilibrium?
A massive star can have more fuel than a smaller star but still die sooner because it does this.
What is uses up its fuel faster?
This kind of reasoning uses a claim, evidence, and an explanation of how the evidence supports the claim.
What is claim-evidence-reasoning?
Once a young star reaches the main sequence, gravity pulling inward is balanced by pressure pushing outward from energy made in the core. This balance is called this.
What is hydrostatic equilibrium?