There is much concern in many circles about the rise in global temperatures. The discussion should not be about whether man and his strong influence on the environment is to blame, or whether we just happen to be in another warming stage of the earth's natural cycles of warming and cooling.

Science has proved without doubt that global temperatures are rising. Temperatures have risen with app. 3 degrees average over the last 100 years, causing enormous changes in ocean levels, destruction of eco-systems and habitats, threatening global food production, increase in number and verocity of hurricanes as well as a speeded up process of desertification.

There are many ideas and projects being developed in order to reverse this trend. Some of them we can all be part of such as reduction in carbondioxide emissions. Others can only be developed by scientists, astronomers and high tech engineers.

An amazing project is being developed by astonomer Roger Angel. The project, known as Project Sunshield came about due to his, and many other's, concern over global warming through solar radiation.

The basic idea is to construct a shield of light reflecting lenses and place it at a certain distance from earth. The shield is to consist of trillions of light relecting lenses. This shield will deflect some 2% of sunlight, enough not just to stabilize earth's climate, but actually lower temperatures to a level equivalent of pre-indstrial levels.

The shield was originally to consist of trillions of 2-foot lenses to be placed at the Lagrangian or L1 point (1 million miles from earth). The Lagrangian point is the point in space where gravity from either the sun or the earth has no effect. Placing a shield of light reflecting lenses here will mean guaranteeing that the shield will stay in place.

The cost of producing and launching lenses of this size into space stands in the trillions of trillions of dollars, basically ruining earth's economy for centuries. A more feasable solution was needed.

Roger Angel together with Dr. Basil Singer and the Delft Institute in Holland have developed a smaller light reflecting lens with the same properties. The new lenses are feather light, .04 ounces (1 gram) and inch in diameter, and will be able to perform the same function as the larger lens.

Once delivered into space the lenses would create a "cloud" 62.000 miles long, and be able to
defract some 2% of the sun's light, enough to lower global temperatures to pre-industrial levels.

The estimated cost of placing a payload into a position like the L1 is $20.000 per kilo payload using rockets. Even with the reduction in weight of the lenses, this make the project unfeasible.

The only other option available at present is the coil gun. The coil gun is also still in the developing stages. But the coil gun, according to Dr. Angel is still the best bet.

The Space Sunshield can do a lot of the work needed to influence the earth's natural cycles global warming, but it cannot stand alone, according to Dr. Angel. Reduction in greenhouse gases through lowered emissions is an additional must.