NASA Develops Comet Slaying Space Harpoon
NASA Articles 12/15/11
By: Chris Capps
The idea of harpooning a comet seems in some way similar to the story of Moby Dick and the Great White Whale. But as humanity's ambitions escalate to titanic proportions, a new development by NASA will make safe what would ordinarily be an extremely dangerous mission - the harpooning of an entire comet as it soars through space.
The idea of harpooning a comet seems awfully ambitious for a space agency that has now canceled its means of getting people off the ground and into orbit. But the new tool, which would be launched from an unmanned spacecraft up to a mile away from the comet it orbited would allow for scientists to collect samples from its surface within the comet and bring them back to suggest to scientists what the whole of the comet might look like - and how life might be formed in the future.
Of course getting near a comet is going to be difficult enough, but once the comet orbiting probe gets there it's going to have to find a way to actually aim the harpoon and then ultimately fire it. Aiming a harpoon might sound like an easy enough task on something roughly a mile in diameter, but keep in mind in the vacuum of space there have been only a limited number of tests on just how projectiles might work. Of course NASA will likely be conducting tests like these to discover how the devices will work.
At the moment the firing mechanism of the harpoon is very similar to a crossbow, like on Earth. While a bullet in space would likely work to propel the harpoon into the comet, effectively retrieving the sample, the action of the crossbow would drive the arrow into the comet in a controlled and hopefully predictable way with bull's eye accuracy before a small explosive charge on the end of the arrow detonated and launched the bolt away from the surface of the comet. The crossbow design is simple to make and requires fewer moving parts in the vacuum of space than a traditional cannon or rifle would.
Common sense suggests a bullet would not fire in space without the oxygen required to fire it, but most bullets contain all the ingredients necessary to fire even without oxygen around them, even on Earth. This is one of several reasons fires in ammunition factories can be a problem even long after smoke and other impurities are too dense to reliably provide oxygen for the bullets - as they will fire with or without the oxygen just with the gas contained within the primer.
Regardless, bullets are not on the menu for this first space weapon, instead favoring the more traditional look of a harpoon. Perhaps in time we will have a look at what the inside of a comet looks like, but it will be a long journey there and back - and it looks like NASA is ready with its comet slaying crossbow.