Post by rmarks1 on Aug 7, 2018 21:34:16 GMT -5
Is Humanity About To Accidentally Declare Interstellar War On Alien Civilizations?
So let's say we get it right. We develop the right material to reflect enough of the laser light that it doesn't incinerate the sail. We collimate the lasers well-enough and build a large-enough array to accelerate these starchip spacecrafts to their designed speeds of 20% the speed of light: ~60,000 km/s. And then we aim them at a planet around a potentially habitable star, such as Alpha Centauri A or Tau Ceti.
Perhaps we'll send an array of starchips to the same system, hoping to probe these systems and gain more information. After all, the main science goal, as it's been proposed, is to simply take data during arrival and transmit it back. But there are three huge problems with this plan, and combined, they could be tantamount to a declaration of interstellar war.
The first problem is that interstellar space is full of particles, most of which move relatively slowly (at a few hundred km/s) through the galaxy. When they strike this spacecraft, they'll blow holes into it, rendering it into cosmic swiss-cheese in short order.
The second is that there's no reasonable deceleration mechanism. When these spacecrafts arrive at their destination, they'll still be moving at roughly the speeds they took off at. There's no stopping to take data or a gentle orbital insertion. They move at the speeds they move at.
And the third is that aiming to the level-of-precision needed to pass close to (but not collide with) a target planet is virtually impossible. The "cone of uncertainty" for any trajectory will include the planet we're aiming for...
Even if we make this mass tiny, it's still going to cause some damage. A planet getting hit by a ~1 gram spacecraft moving at 60,000 km/s is going to experience the same level of catastrophic effects as a planet getting hit by a ~1 tonne asteroid moving at ~60 km/s, the equivalent of which happens on Earth just once per decade. Each strike would hit their world with the same energy that the Chelyabinsk meteorite struck Earth: the most energetic collision of the decade.
If you were an alien on this world that got struck by these relativistic masses, what would you conclude? You'd know that these were too massive and too fast-moving to be created naturally; they were made by an intelligent civilization. You'd know that you were being intentionally targeted; space is too vast for these to strike you by random chance. And — worst of all — you'd assume this civilization had a malicious intent. No benevolent aliens would launch something so recklessly and carelessly given the damage it would cause. If we're smart enough to send a spacecraft across the galaxy to another star, surely we can be wise enough to reckon the disastrous consequences of doing so.
www.forbes.com/sites/startswithabang/2018/08/07/is-humanity-about-to-accidentally-declare-interstellar-war-on-alien-civilizations/#37673acb26a9
So let's say we get it right. We develop the right material to reflect enough of the laser light that it doesn't incinerate the sail. We collimate the lasers well-enough and build a large-enough array to accelerate these starchip spacecrafts to their designed speeds of 20% the speed of light: ~60,000 km/s. And then we aim them at a planet around a potentially habitable star, such as Alpha Centauri A or Tau Ceti.
Perhaps we'll send an array of starchips to the same system, hoping to probe these systems and gain more information. After all, the main science goal, as it's been proposed, is to simply take data during arrival and transmit it back. But there are three huge problems with this plan, and combined, they could be tantamount to a declaration of interstellar war.
The first problem is that interstellar space is full of particles, most of which move relatively slowly (at a few hundred km/s) through the galaxy. When they strike this spacecraft, they'll blow holes into it, rendering it into cosmic swiss-cheese in short order.
The second is that there's no reasonable deceleration mechanism. When these spacecrafts arrive at their destination, they'll still be moving at roughly the speeds they took off at. There's no stopping to take data or a gentle orbital insertion. They move at the speeds they move at.
And the third is that aiming to the level-of-precision needed to pass close to (but not collide with) a target planet is virtually impossible. The "cone of uncertainty" for any trajectory will include the planet we're aiming for...
Even if we make this mass tiny, it's still going to cause some damage. A planet getting hit by a ~1 gram spacecraft moving at 60,000 km/s is going to experience the same level of catastrophic effects as a planet getting hit by a ~1 tonne asteroid moving at ~60 km/s, the equivalent of which happens on Earth just once per decade. Each strike would hit their world with the same energy that the Chelyabinsk meteorite struck Earth: the most energetic collision of the decade.
If you were an alien on this world that got struck by these relativistic masses, what would you conclude? You'd know that these were too massive and too fast-moving to be created naturally; they were made by an intelligent civilization. You'd know that you were being intentionally targeted; space is too vast for these to strike you by random chance. And — worst of all — you'd assume this civilization had a malicious intent. No benevolent aliens would launch something so recklessly and carelessly given the damage it would cause. If we're smart enough to send a spacecraft across the galaxy to another star, surely we can be wise enough to reckon the disastrous consequences of doing so.
www.forbes.com/sites/startswithabang/2018/08/07/is-humanity-about-to-accidentally-declare-interstellar-war-on-alien-civilizations/#37673acb26a9
Bob
