Recap 8

1. On a one-billionth scale, wherein Earth is the size of a grape, the nearest _____________ would be at a distance greater than the diameter of the actual Earth.

2. Our solar system is located in one of the spiral ______ of what we call the Milky Way Galaxy, about _____________ light years from the galaxy’s center.

3. One of the difficulties of searching for intelligently modulated signals of extraterrestrial origin is guessing what _______________ another intelligent species might use for its signal.

1.star 2. arms, 30,000 3. frequency (or wavelength)