Astronomy Cosmology and Deep Space

Question 1

What is the Big Bang theory?

Accepted Answer

The prevailing cosmological model explaining the universe's origin from an extremely hot, dense state approximately 13.8 billion years ago

Answer

A theory about how stars explode

Answer

A model explaining only galaxy formation

Answer

A disproven hypothesis about the universe

Question 2

What is dark matter?

Accepted Answer

An unknown form of matter that doesn't emit or absorb light but exerts gravitational effects, comprising about 27% of the universe

Answer

Matter that exists only in darkness

Answer

Black holes collectively

Answer

Antimatter in deep space

Question 3

What is the cosmic microwave background radiation?

Accepted Answer

Faint radiation from approximately 380,000 years after the Big Bang, filling all of space uniformly

Answer

Radio signals from distant alien civilizations

Answer

Radiation from the Sun reflecting off cosmic dust

Answer

Light from the first stars

Question 4

What is Hubble's Law and what does it tell us about the universe?

Accepted Answer

The recessional velocity of galaxies is proportional to their distance — evidence that the universe is expanding

Answer

Stars are moving toward the Milky Way

Answer

The universe is shrinking

Answer

Galaxies orbit around a central point

Question 5

What is a galaxy and what types exist?

Accepted Answer

A gravitationally bound system of stars, gas, dust, and dark matter; types include spiral, elliptical, and irregular

Answer

A single large star

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A cluster of planets

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A nebula

Question 6

What is gravitational lensing?

Accepted Answer

The bending of light from distant objects by the gravity of intervening massive objects, as predicted by general relativity

Answer

A type of telescope lens

Answer

Gravity affecting only light near black holes

Answer

An optical illusion in Earth's atmosphere