Why Beautiful Clouds Are Worrying Scientists

What makes noctilucent clouds so captivating to observers?

• Their occurrence during winter

• Their ghostly luminescence

• Their formation in the troposphere

• Their ability to emit light

How do noctilucent clouds get their glowing appearance?

• By emitting their own light

• By reflecting solar radiation

• By absorbing moonlight

• By scattering starlight

Why is the mesosphere a challenging region to study?

• It's too low for aircraft and too high for spacecraft

• It's too warm for scientific instruments

• It's too dense for satellites

• It's too high for aircraft and too low for spacecraft

What is the mesopause anomaly?

• The mesosphere has constant temperatures year-round

• The mesosphere is warmer in summer than in winter

• The mesosphere is colder in summer than in winter

• The mesosphere is warmer at night than during the day

What is one theory about the source of dust for noctilucent clouds?

• Dust from volcanic eruptions

• Dust from oceanic evaporation

• Dust from the Sahara Desert

• Dust from space debris

How did the United States Naval Research Laboratory create an artificial noctilucent cloud?

• By simulating volcanic eruptions

• By using a weather balloon

• By releasing water from a satellite

• By using exhaust particles from a rocket

What is the purpose of NASA's AIM satellite?

• To track meteor showers

• To study the troposphere

• To measure ocean temperatures

• To investigate noctilucent clouds