Has Earth Been Visited?

Last night I was reading Discover, a science magazine. The cover story dealt with the new, mammoth telescopes presently under construction that may actually show us planets about nearby stars.
Presently we know of over a hundred extrasolar planets, as they are called, but detect them by looking at wobbles in the position of the star. We haven’t actually seen them. From our distance, the dots would be too tiny, lost in the glare of the star that is their sun. A sentence in the article stuck me. While describing the discoveries the next giant telescope might make, the author wrote, “For now, we know of life on just one planet around just one of the [billions of billions] of stars in the known cosmos.”
I paused, and reflected that almost everyone reading the article would agree. Although we reason that there is a high probability that life exists elsewhere in the universe, scientists are still awaiting concrete evidence. I asked myself, however, what the majority of people not reading the article thought.
Having been a secondary school science teacher, I know what many high school students would tell you. With great excitement, they would announce that alien spacecraft make crop circles, that stone-age paintings on cave walls show spacemen, that there are dead aliens in an air force hanger near Roswell, New Mexico.
Many adults believe these tales, too. While scientists spend time and money searching for life, even mere microbial life, off the Earth, vast numbers accept that Earth has already been visited by alien life forms.
Four hundred years ago, learned people considered Earth to be in the centre of the universe. Now, astronomers teach that Earth is a small rock orbiting an average star in the outskirts of a spiral galaxy that contains billions of stars. Decades passed, though, before most intelligent people stopped saying, “I still believe Earth is in the centre.”
Two hundred years ago, many intelligent, learned people had no trouble accepting that the Earth was about six thousand years old. Scientists universally accept that the planet has been around for billions of years.
Sixty years ago the concept that the continents are moving was taken dubiously, but continental drift is standard policy now. The motions of the great land masses are measurable, and their collisions cause mountains to rise and the earth to quake.
Are there people now who reject the changed perspectives, people who consider the Earth to be young, in the centre of the universe, and composed of stationary continents? If so, would they be reading science magazines? And if so, would they be continually shaking their heads over the hundreds of incorrect statements from the world’s astronomers, biologists, geologists, chemists, and physicists?
I don’t maintain that all scientists agree with each other on every topic. Part of the fun of science is the constant debate, the tussles over the details and explanations. There is near universal agreement, though, on the big issues, one being that there is no good evidence for life off the Earth, now or in the past.