Exam 19: Life in the Universe: Are We Alone

What do we mean by "life as we know it"?

Life emerged on Earth within about a billion years after the solar system formed.

How does Drake define a technological civilization?

If a star system 30 parsecs distant is found to be broadcasting intelligent radio signals, then their news is already approximately years old.

Astronomical events, such as an asteroid impact or nearly supernova, have probably altered the course of evolution on Earth.

Around Sun- like stars, we have, to date, only found Jupiter- like planets.

In a galaxy like ours, the best place for life to form would be in the .

The equation was written to assess the probabilities of technological, intelligent life existing in the Galaxy.

Which factor in the Drake equation is the most uncertain?

According to our definition, we have been a technological civilization for about

Which of these radio waves would fall in the "water hole"?

The Miller- Urey experiment sought to recreate conditions in Earth's early atmosphere.

Why does Europa's surface promise life of some kind?

As the average estimated lifetime of a technical civilization increases, then the distances between neighboring civilizations would _ _.

Compared to a G- type star, an F- type will have a(n) habitable zone.

Of the billions of possible combinations of atoms into organic molecules, only about 1500 actually occur.

How did the Miller- Urey experiment attempt to recreate early conditions on Earth?

Contrast space flight and radio communication as possible means of SETI.

The one term of the Drake equation whose value remains completely unknown is the average lifetime of a technological civilization.

What role did Frank Drake play in SETI?