At present, it seems impossible to visit the satellites of other stars in search of life. Our present theories of physics indicate that it is impossible to move at a speed greater than that of light. Even at such a speed it would take many years to reach the nearest star that might have planets. Most of such stars are many lifetimes away.
Perhaps someday we shall invent ways of traveling or sending messages that will allow man to find other living things in the universe.
Even more interesting is the possibility that they may find us! If the steady-state theory of the universe is correct, there must be many "solar systems" that are much older than ours. On some of these, intelt life may have evolved (进化) long ago. If so, these creatures might be exploring the universe today.
Serious scientific projects in recent years have been studying the skies with radio telescopes, hoping to find signals sent by such intelt beings. It has been suggested that the puzzling quasars (类星体) might b e the wakes (航迹) left by spaceships traveling faster than light.
Thus far, we have found no definite evidence of other intelt life in the universe. Perhaps we never shall. Yet the search and the hope will remain an exciting possibility for the future. Which of the following statements is TRUE according to this passage