There is still danger in space

by Bob Kobres

The Athens Observer (12/10/92) 

The EDITOR: Ten years ago (11/24/82) The Observer published a condensed version [109k GIF] of a paper I was then circulating. My topic was the threat posed by Earth-orbit-crossing objects and how this danger afforded an opportunity for East and West to build mutual trust by working together to effect a viable defense against these otherwise inevitable intruders from space. Such an idea was generally considered pretty far out a decade ago and it is to The Observer's credit that publication of this suggestion was allowed.

Now that the danger from Earth-orbit-crossing objects is becoming common knowledge (see Newsweek 11/23/92) it is easier to focus on the particulars of the situation.

Of great importance is realizing that impact events have adversely affected humanity recently. This is due primarily to the break-up of a very large (greater than 100 kilometers across) short period (approximately 3.3 years) Earth-orbit-crossing comet during the last 15,000 years.

The once flamboyant cosmic interloper increased the supply of potential impactors and so elevated the average rate of impact. This comet, the progenitor of comet Encke, the Taurid meteor complex, and several large dark objects (inactive comet nuclei), seems to have been feared and worshipped ubiquitously.

Knowing that our ancestors witnessed phenomena associated with the devolitization of this comet make understandable the widespread belief in a wrathful sky-god as well as the idea that the position of celestial bodies could affect events on Earth. To gain a better understanding of this fascinating aspect of extraterrestrial influence, find a copy of The Cosmic Winter by British astronomers Victor Clube and Bill Napier.

Equally important is realizing that a contemporary impact event would be far more damaging than an equivalent past collision. The reason for this is that the damage to the biosphere done by an impactor would now be superimposed upon the stress we as a species are currently placing on the living system that envelopes Earth.

Clearly, a high priority needs to be placed on preventing future smash-ups with celestial objects larger than 50 meters (around a 10 megaton event). These small objects (50 to 100 meters) are the most numerous (est. 300,000) and so hit often (about twice per century). The 1908 Tunguska impact was of this size range and by heat generated oxides of nitrogen temporarily reduced ozone content in the northern hemisphere by an estimated 30 percent. To locate these most abundant objects we need observation devices in space.

I urge readers to convey support for internationally cooperative space development to the incoming administration. Developing an Earth defense system is an excellent way to convert weapon industries into the productive occupation of protecting Life on our planet. Furthermore, evolving the ability to detect and deflect objects in space can facilitate utilizing these cosmic missiles as raw materials. This in turn could make it possible to begin phasing out environmentally destructive industries such as mining and smelting within the biosphere. Ultimately all manufacturing processes toxic to the environment could be accomplished in space with power freely collected from solar output.

With resolve, this means of pollution source elimination could be realized by the middle of next century.