The Big Questions

The questions themselves may be expressed simply enough: In this universe, are we alone? Is there life—other than on Earth—within the solar system? The Galaxy? Beyond? If so, is it intelligent? And if intelligent, will it communicate with us? Then on to questions about the origin and fate of the universe. Is the universe eternal? If not, how did it begin? And how will it end? Is the universe infinite?

The questions may be put simply enough. The answers ... well, read on.

In This Chapter

V Is the earth unique or typical in its ability to sustain life?

V Emergence of life on the earth

V Is there other life in our solar system?

V The case for life on Mars

V Life in our Galaxy: the Drake Equation

V The search for extrasolar planets

Throughout this book we have been exploring distant worlds, places that are incompatible with any life we can imagine. We have traveled from the burning and frigid surfaces of the other planets in our solar system to the cores of stars generating the tremendous temperatures of nuclear fusion, to the neighborhoods of black holes that spit jets of charged particles into intergalactic space. These are not exactly life-friendly environments. But, undeniably, we are here. Our planet is literally crawling with all variety of life. Is our planet really so unique in the universe?

Probably not.

We have learned that there is nothing particularly special about our position in the cosmos: We inhabit the third planet orbiting an average star in a solar system tens of thousands of light-years from the center of a normal spiral galaxy. And there are a few hundred billion other stars in the Galaxy.

So if we're not so special, why has no one contacted us to let us know? Do we smell bad? Is it our hair? Or is our planet truly the only repository of life in the universe? (Hollywood seems to think not.) In this chapter we ask a big question, "Are we alone?" And if we aren't alone, where is everybody?

Telescopes Mastery

Telescopes Mastery

Through this ebook, you are going to learn what you will need to know all about the telescopes that can provide a fun and rewarding hobby for you and your family!

Get My Free Ebook

Post a comment