The terrible death of the seven Columbia astronauts has left a coruscating, yet indelible, mark upon millions of minds worldwide.

There is something monumentally tragic and unjust about innocent people being incinerated to death in this way. We feel especially helpless because the event was so public, almost visible in the shuttle's trail, and yet nobody could do anything to stop it. Many will particularly mourn Kalpana Chawla, known for her spirit of adventure, humility and decency.

The Columbia mishap temporarily sets back the cause of exploring space and expanding the frontiers of knowledge. Regrettable as this is, the loss shouldn't be exaggerated. For, it's a mistake to think that NASA's programmes are entirely about science, and that actually existing space exploration can be divorced from military objectives.

Most space missions have 'dual use'. Sometimes, the military uses are overwhelming. In the US, the Pentagon increasingly "rides the NASA horse", says the Florida-based Global Network Against Weapons and Nuclear Power in Space.

There are other problems too. NASA has been putting ultra-hazardous materials into space. There are disturbing disclosures by the US National Public Radio that Columbia had radioactive material on board - a fact confirmed by the sheriff of Nacogdoches, Texas. People in debris-affected areas were given a 'list of priorities': anything resembling computer circuitry, or 'potentially radioactive materials' (AP). According to other reports, the mission carried three military projects, on which NASA is remarkably unforthcoming.

NASA plans to use more nuclear materials. Through 'Project Prometheus', it wants to broaden its $ 1 billion 'Nuclear Systems Initiative' to develop a nuclear-propelled rocket. It is also due to launch two rockets carrying Mars rovers, equipped with plutonium-powered heaters.

Some readers might recall the huge controversy back in the Seventies over recovering from the high Himalayas a plutonium pack planted by the US secret agencies, presumably to power spying equipment.

These poisonous materials have an unacceptably high probability of being released into space and the atmosphere. NASA's own Environmental Impact Statement says: "The overall chance of an accident (for each launch) is about 1 in 30 (and that of) any accident that releases radioactive material to the environment is about 1 in 230." Imagine people inhaling radionuclides from launches, and worse, a nuclear reactor breaking up over a city!

Reprehensibly, NASA has ignored both safety warnings and benign technologies (like solar) for energising space systems. NASA's 'partnership' with the military-nuclear complex seems to be the principal culprit here. Another is grant cuts, because of which NASA has increasingly turned to the Pentagon for funding.

The use of nuclear materials in spacecraft and rockets is part of the much larger, four-decade-long process of militarisation of space. This has happened through intelligence, communications and command satellites, sensors and other military-related equipment, and above all, through ballistic missiles. A typical long-range missile - and some 50,000 of these were around at the height of the Cold War - leaves the Earth's atmosphere and reenters it via space to hit its target.

The US aims to dominate space as 'the strategic high ground from which to project power', including developing lasers, 'kinetic-energy rods' or other weapons to attack spacecraft, missiles or ground targets.

A Defence Department Space Programme Over-view states: "Space has often been referred to as 'the high ground' giving its occupier a dominating view (and prospective control) of a potential battlefield. Space forces play an increasingly important role in prosecuting modern warfare. They provide surveillance, ballistic missile warning, precise navigation, secure communications, weather and intelligence They facilitate 'effective command and control'."

The US Space Command's motto, outlined in Vision for 2020, reads: "Dominating the space dimension of military operations to protect US interests and investments. Integrating Space Forces into warfighting capabilities across the full spectrum of conflict." The document lists 28 official agencies and 49 corporations like Boeing, Lockheed-Martin and TRW as 'shaping' our 'space capabilities'.

However, the greatest damage to space will come from the US's Ballistic Missile Defence (BMD) programme, approved by George Bush for deployment in 2004 in its first stage. This involves creating a shield against incoming missiles: by detecting their launch and intercepting them during their trajectory, including importantly, through space. This technology is, as of now, totally immature and unreliable. A majority of interceptor tests have failed: the chances of accurately hitting a bullet flying at 20,000 kmph with another flying at the same velocity are understandably low. Decoys can fool too.

The US has spent $ 120 billion on BMD - without significant results. In the mid-Seventies, it also built 'Safeguard' to protect missile silos. This cost $ 194 million in a day to operate, but didn't work.

Technological folly apart, even developing BMD will be a major menace. It will leave enormous debris in space, some toxic or radioactive. It will also mean placing dangerous lasers and directed-energy weapons on space platforms.

Three issues arise. Has anyone the moral right to pollute and desecrate space - even for 'national security'? Ethically, the unambiguous answer is no. It makes no sense to intrude into the extra-terrestrial universe and militarise or pollute it. Going by the mood among the vast majority of governments, politically too the answer is negative.

Secondly, militarisation of space will lead to a horrific, new, no-holds-barred arms race, destabilising global security, with destructive consequences for commercial, communication, verification and intelligence-oriented space-assets.

Finally, India, to its disgrace, lent uncritical support to America's BMD and was more loyal than the king in welcoming it in May, 2001. It calculates that servility will get it a slice of the (toxic) BMD cake. Isn't it time to think in less narrow, chauvinist and militarist terms - and help keep The Last Frontier free of lethal weapons?