Big Bang Theory
What is the name of the theory that describes the rapid expansion of the universe?
The Big Bang Theory
What are galaxies primarily made of?
stars, gas, dust, and dark matter
The beginning stage of a star’s life cycle is known as what?
a protostar
What is gravity?
a force of attraction between any two objects with mass
What is an orbit?
The path one object takes around another due to gravity.
How do scientists gather evidence about the early universe?
By studying the motion of galaxies and their redshifts.
Name the three main types of galaxies.
spiral, elliptical, and irregular galaxies
The most massive stars collapse to form what when they die?
a black hole
How did gravity help form the sun?
gravity pulled together gas and dust to create the sun
How does the motion of Earth around the sun affect our seasons?
The tilt of Earth's axis and its orbit around the sun causes seasonal changes.
What is redshift and how does it relate to the movement of galaxies?
The change in light from galaxies moving away from us, indicating the universe is expanding.
How do galaxies move in relation to each other?
they are moving away from each other due to the expansion of the universe
How can scientists determine the composition of a star?
By analyzing the light spectrum emitted by the star.
How does gravity affect the shape of planets?
gravity pulls matter into a round, spherical shape
What is the difference between rotation and revolution?
Rotation is when an object spins on its axis, while revolution is when it orbits another object.
Describe one piece of evidence that supports the Big Bang Theory.
the cosmic microwave background radiation
What role do stars play in the universe?
they create light and heat and are essential for the formation of elements
How does the life cycle of a star depend on its mass?
More massive stars burn hotter and faster, leading to different end stages like super nova.
Describe how gravity affects the orbits of planets.
Gravity from the sun pulls the planets towards it, while their motion keeps them in orbit.
How does the Earth's rotation affect day and night?
the rotation causes different parts of Earth to face the sun or be in shadow
Why is it important to analyze the composition of stars when studying the universe's beginning?
it helps us understand the elements formed after the Big Bang
Explain how the motion of galaxies provides evidence for the Big Bang.
galaxies are moving away from us suggesting the universe is expanding
A dying high-mass star can suddenly explode, becoming a what?
Supernova
Explain how gravity impacts the formation of ocean tides on Earth.
The gravitational pull of the moon and sun causes the rise and fall of ocean water levels.
How does gravity affect the motion of celestial objects in our solar system?
It controls the orbits of planets, moons, and other bodies, keeping them in stable paths.