This thing is -270°C and is EVERYWHERE

What was the initial reaction of Wilson and Penzias to the mysterious signal they discovered?

• They immediately recognized it as the CMB.

• They ignored it as irrelevant noise.

• They thought it was a mistake or interference.

• They believed it was a signal from another planet.

What is the cosmic microwave background primarily composed of?

• Gamma rays

• Microwaves

• Ultraviolet radiation

• Visible light

Why is the early universe described as 'opaque'?

• Because it was completely dark.

• Because it was filled with black holes.

• Because light couldn't travel freely due to dense plasma.

• Because it was filled with dark matter.

What significant event allowed light to travel freely across the universe?

• The creation of galaxies

• The Big Bang

• The recombination of electrons and protons into atoms

• The formation of stars

How do scientists map the cosmic microwave background?

• By sending specialized probes into space

• By observing solar flares

• Using optical telescopes

• Through ground-based radio antennas

What does the Sunyaev-Zel'dovich effect help scientists understand?

• The formation of stars

• The temperature of the CMB

• The effect of dark energy on the universe's expansion

• The age of the universe

What is the current average temperature of the cosmic microwave background?

• 100 Kelvin

• 0 Kelvin

• 2.7 Kelvin

• 3000 Kelvin