Sir, - NASA has set October 6th, 1997 as the date to launch a probe to travel to Saturn on a discovery mission. Another great pioneering endeavour into space by humankind, one might say. Yes, but at what price? The electrical instruments aboard the Cassini probe require plutonium 238 to power them. This could, if released into Earth's atmosphere, according to nuclear physics professor Dr Michio Kaku of New York City University, cause "the most toxic chemical known to science" to "shower down with a tremendous tragedy for the people of the Earth".
Although NASA claims the risk is small, even if one pound of this extremely toxic substance were evenly distributed about the globe, it would be enough to give lung cancer to every living person.
There are two stages in the Cassini Mission when there is serious danger of radiation exposure. The first is at the launch of the Titan IV rocket, which has a failure contingency rate of between one in ten and one in twenty. The other is when the probe, voyaging from Venus, circles Earth to increase its velocity for the long journey to Saturn. If a miscalculation brings the vessel within our 75 mile-high atmosphere, the plutonium will be released when the probe disintegrates.
The European Space Agency estimated in 1995 that if it had the finance, solar cells could be developed which would be capable of sending a mission to Saturn within five years. This alternative is more viable and radically safer; in fact, it is the common sense option. It is imperative that we voice our horror now at both the unnecessary gamble that NASA is taking and the unimaginable consequences that could ensue if there is either a mechanical malfunction or human effort in calculation. Can we afford to play roulette with our lives by staying silent? - Yours, etc
Knocklyon, Dublin 16.