Exam 24: Life in the Universe

The Kepler mission searches for Earth-like planets by looking for the dip in the brightness of a star as such a planet transited across it.Why does this technique actually miss the vast majority of planets?

If the carbon isotope evidence does indicate life 3.85 billion years ago,it suggests that life must have been widespread at that point.

Einstein's theory of relativity tells us that travelers who make a high-speed trip to a distant star and back will

Looking for an Earth-size planet around a nearby star (besides the Sun)is like looking for a pinhead located

If we develop spacecraft that can take humans to nearby solar systems at a few percent of the speed of light,how long would it be before we could conceivably populate all habitable planets in the entire Milky Way?

How does the Kepler mission plan to detect Earth-like planets around other stars?

What evidence do we have that life arose quickly?

Which of the following statements about matter-antimatter engines is not true?

"Super-Earths" may be habitable at distances much greater from their star than Earth.

Even if Martian meteorites contained life,the life could not possibly have survived the journey from Mars to Earth.

It is possible that there are moons within habitable zones that have habitable surfaces in other solar systems.

Which of the following causes mutations in living organisms?

The Sun's habitable zone

Although antimatter is an interesting theoretical idea,there is no evidence that it actually exists.

Why didn't oxygen begin to accumulate in the atmosphere until approximately 1.5 billion years after life appeared on Earth?

Which of the following is considered by biologists to be a likely place where life first arose on Earth?

At present,what is the primary way that the search for extraterrestrial intelligence (SETI)is carried out?

We are unlikely to find fossil evidence of life from more than 3.5 billion years ago because there is no way life existed before then.

In 1974,a radio message was sent out from the Arecibo observatory in Puerto Rico.How far has it gotten,approximately?

In the equation: Number of Civilizations =Np × flife × fcivilization × fnow What do we mean by fnow?