Cosmic Phenomena

How do we know that dark matter exists?

• Because of the expansion of the universe

• Because of how it impacts gravity

• Because of the dark color of empty space

• Because of the radiation it emits

Answer explanation

Dark matter is known to exist because of how it impacts gravity, affecting the motion of galaxies and bending light in gravitational lensing.

Tags

NGSS.HS-PS2-4

A galaxy that gives off RED light means it is moving AWAY from us.

• TRUE

• FALSE

Answer explanation

A galaxy emitting red light is moving away from us due to redshift, indicating the Doppler effect and expansion of the universe. Therefore, the statement is TRUE.

Tags

NGSS.HS-ESS1-2

What happens to the orbit velocity of stars as you move further away from the center of the galaxy?

• increase

• decrease

• all are the same

• no pattern

Answer explanation

The orbit velocity of stars remains the same as you move further away from the center of the galaxy, hence all are the same.

What is dark energy?

• electrified form of dark matter

• a repulsive force that counteracts gravity

• force found in black holes

• force of the universe

Answer explanation

Dark energy is a repulsive force that counteracts gravity, not an electrified form of dark matter, force found in black holes, or force of the universe.

How do scientists know how much dark energy is in the universe?

• Dark energy is double the amount of dark matter

• Calculating the energy needed to move a galaxy

• There is half as much dark energy as there is spacetime

• Studying the CMB and the energy needed to overcome gravity

Answer explanation

Studying the CMB and the energy needed to overcome gravity is how scientists determine the amount of dark energy in the universe.

Why is the AGE and LOCATION of the first flash of light so significant?

• It is almost the same AGE of the Universe & found everywhere

• It is older than the Universe and only found in the center

• It is almost the same age as the Universe and emitted by all stars

• It is half the age of the Universe and emitted by each galaxy

Answer explanation

The first flash of light is significant because it is almost the same age as the Universe and can be found everywhere, indicating its widespread presence.

Tags

NGSS.HS-ESS1-2

Hubble's Law states if an object is FARTHER away it moves at a _________________ velocity.

• faster

• slower

• average

Answer explanation

According to Hubble's Law, if an object is FARTHER away, it moves at a faster velocity, as the distance between objects increases, their relative velocity also increases.

Tags

NGSS.HS-ESS1-2

What evidence supports the Big Bang Theory?

• Discovery of cosmic microwave background radiation

• Observation of galaxies moving towards us

• Stable distribution of matter in the universe

• Uniform temperature of cosmic rays

Answer explanation

The discovery of cosmic microwave background radiation provides evidence for the Big Bang Theory.

Tags

NGSS.HS-ESS1-2

What is the significance of the cosmological redshift?

• It indicates the universe is contracting

• It suggests the universe is expanding

• It shows galaxies are moving towards us

• It proves the Big Bang never happened

Answer explanation

The cosmological redshift suggests the universe is expanding, as the light from distant galaxies is shifted towards longer wavelengths due to the expansion of space.

Tags

NGSS.HS-ESS1-2

What phenomenon explains the acceleration of the universe's expansion?

• Dark matter

• Dark energy

• Black holes

• Quantum fluctuations

Answer explanation

Dark energy is the phenomenon that explains the acceleration of the universe's expansion, not dark matter, black holes, or quantum fluctuations.