§ 5.15: SETI - the Search for Extra-Terrestrial Intelligence
Man is the dominant species on Earth and in its solar system, but man probably is not nearly the greatest life form in the Universe.
The social impact on societies on Earth of discovering more highly evolved life beyond our solar system may be greater than any other discovery to date. In the last 100 years of man, just an infinitesimal instant of time since the Universe evolved into existence, man has discovered much more about himself and the Universe than in all of previous history combined. The next 100 years will certainly be even greater.
Technology has now given us the capability to seek and find other life in the Universe, by detecting their TV transmissions and other communications, beacons, and activities. However, nations must make the committment to apply financial resources to apply present-day technology to this historic goal for life on Earth -- to find out about other, still higher life elsewhere in the Universe.
It won't cost much, but it is currently paid for largely by tax dollars thanks to politicians. It's a nonprofit endeavor.
A giant radio telescope located in space would be much better than what we are using today.
Imagine the impacts socially, individually, culturally, and politically of finding out that greater life exists out there. Perhaps we would be embarrassed about much of our own conduct on Earth, and alot of egos would be scaled down. World peace and cooperation might be increased as people strove for greater heights in view of their deeper awareness of their true role in the Universe and on Earth.
We can achieve this in our lifetimes. What we could use is a telescope the size of a city to capture distant and weak transmissions. We could also use a large telescope to optically focus on a smaller part of the Universe in order to get a better "signal-to-noise ratio" reception. (An analogy is a bigger satellite TV dish in your back yard in order to collect a faint transmission but more importantly to point at (focus upon) a selected part of the sky.)
A telescope the size of a city must be made in space. It would be far too massive in Earth's gravity, and on Earth's surface it couldn't be pointed where we wanted -- we would be limited to straight up and sweeping as Earth rotated. (We might prefer to point at black holes -- possible galactic space transportation ports due to the slingshot effect of "gravity assists".)
It has been seriously proposed to put a radio telescope on the far side of the Moon to block out noise from Earth. We could do better, on the far side of an asteroid or behind a big shield in orbit made from asteroidal nickel-iron metal. That would be much easier and cheaper than building one on the surface of the Moon.
This telescope may also be located far away in the solar system, where the Sun's gravity forms a gravitational lens to focus light by bending it. Einstein pointed out that gravity fields bent light rays. Now we can put this knowledge to use by going to where these bent rays are focused by the Sun's gravity. In this region, distant signals are tremendously amplified. A gravity focus can not be as sharp as a lens or mirror focus, so we will still need a large telescope.
Launching this massive telescope up from Earth and then sending it the rest of the way to deep space would cost too much. We must make most of the telescope from nonterrestrial materials. Asteroidal material is most economical. We need to launch only some mass production equipment, because the vast majority of the mass of the telescope is mass-produced, simple metal collection dish and structural components. The fuel for transport is also abundant in asteroidal material.
The last 50 years of man has seen amazing progress, and the next 35 years can see an evolutionary space program of revolutionary achievements for a better future for ourselves, our children, and the causes of the Free World.