Exam 19: Life in the Universe: Are We Alone

Most radio telescope searches for signs of intelligent life are performed in the water hole.

Earth behaves as an artificial pulsar, with the strongest pulses for alien observers when North America is either rising or setting.

The water hole is important to SETI because it is a(n) _ _ part of the radio spectrum.

Name each of the factors in the Drake equation.

Compare the Copernican principle with the assumptions of mediocrity.

Besides comets and meteorites, we also find organic molecules in the _ deep space.

As yet, no human probe has left our solar system and approached another star.

The water hole lies between 18 and 21 cm in wavelength in the radio spectrum.

The cheapest and probably most effective means of interstellar communication is .

Large molecules found in meteorites and interstellar clouds are evidence that

The simplest life forms appeared on Earth by the time it was how old?

NASA has found definite proof for the past existence of life on Mars.

Most bright blue stars we see with the naked eye are good candidates for life, since they have much larger habitable zones than does the Sun.

Which of the following appears most favored by natural selection?

The water hole is a radio region with lower background noise.

An extraterrestrial observer would pick up the strongest radio signals when

Earth- like planets have been observed outside our solar system orbiting in the habitable zone.

Why are type O, A, and M stars considered poor candidates to find a technological civilization?

The Drake Equation is attempting to find

The radio signals from Earth are greater than those from the Sun.