4 ms·

Lasers are the only workable option, I think. But locating a small object at some km altitude would be nontrivial. And hitting one with a laser would be ~imposs

Lasers are the only workable option, I think. But locating a small object at some km altitude would be nontrivial. And hitting one with a laser would be ~impossible. Also, it would see scattered light long before you hit it directly. And even if it had an autonomous targeting system, there'd be a record of its movements. So it would be very hard so stay anonymous.

anigbrowl 7y ago
Atmospheric scattering seems like a big problem, but not location or targeting. People find satellites by doing long exposures (ideally in the infrared) and then looking for movement that doesn't match the rotation of the earth - indeed, I think it's quasi-automated by now. It's rather astonishing what you can pick up with modern glass - there's videos on YouTube of the space station shot from the ground, and while it just looks like a little squiggly letter H, it's the freaking space station, in space, being imaged on relatively affordable prosumer technology. I know nothing about the power side of lasers and imagine you'd need a decent size truck to hold one capable of setting something on fire at distance and its power supply, but it doesn't seem beyond the bounds of feasibility. Of course, it would be 'easier' to hijack the balloon's guidance system but I assume that about 5 minutes after you started broadcasting on restricted radio frequencies people would be looking for you.
- mirimir 7y ago
  OK. But small balloons at 15-20 km? That don't reflect much light? Seems iffy to me. But maybe so. I wasn't thinking of massive physical damage. Just nuking the FPAs. Or perhaps small rockets. But guidance systems are hugely illegal to develop. Chaff might work to mask movements temporarily. Or wildfires, I suppose. Not that anyone sane would do that.
  - mgamache 7y ago
    "guidance systems are hugely illegal to develop" Curious what laws cover this? I am sure they exist, just not explored this at all. Isn't GPS a 'guidance system'?
    - mirimir 7y ago
      I've seen reference in a few articles about model rocketry.
    - pintxo 7y ago
      > The U.S. government controls the export of some civilian receivers. All GPS receivers capable of functioning above 18 km (59,000 ft) above sea level and 515 m/s (1,000 kn; 2,000 km/h; 1,000 mph), or designed or modified for use with unmanned missiles and aircraft, are classified as munitions (weapons)—which means they require State Department export licenses. [1] [1] https://en.wikipedia.org/wiki/Global_Positioning_System#Restrictions_on_civilian_use https://en.wikipedia.org/wiki/Global_Positioning_System#Rest...
craftinator 7y ago
High velocity, heavy caliber hunting right with accentuated rifling, attached to a heavy servo gimble or robotic arm, telescopic lens, laser range finder. Should be able to shoot these down all day long.
- mirimir 7y ago
  A hunting rifle can reach 10-15 km altitude?
  - galangalalgol 7y ago
    not even close, and none of this is civil disobedience. civil would be to have a movement put multispectral bright lights on top of every car boat plane train bicycle ball cap dog collar and then scatter them everywhere at intersections and parks etc. not sure how bright they would need to be to saturate enough to hide the car or dog. you could track the bright spot till they intersect but then I would be iffy to keep them apart at slow intersections I think.
    - mirimir 7y ago
      This is a great idea! Prices of bright LEDs have dropped considerably in recent years. So it wouldn't require that much energy. With enough bright spots, scatter would complicate tracking anything specific. Also, that'd provide cover for the occasional targeted high-energy laser pulse.
raxxorrax 7y ago
It is easier to find the control room and drop the pants of operators.
dredmorbius 7y ago
Blinding sensors, disabling transmitters (beamed energy / emp burst?), disrupting transmissions, or disabling the platform itself (balloon) would be the most obvious choices. Legal challenges.
ptero 7y ago
Location and targeting are trivial (as others said balloons will likely have ADS-B or similar transponders). But your laser (prep and action) will be super easy to detect, too.

anigbrowl 7y ago

Atmospheric scattering seems like a big problem, but not location or targeting. People find satellites by doing long exposures (ideally in the infrared) and then looking for movement that doesn't match the rotation of the earth - indeed, I think it's quasi-automated by now. It's rather astonishing what you can pick up with modern glass - there's videos on YouTube of the space station shot from the ground, and while it just looks like a little squiggly letter H, it's the freaking space station, in space, being imaged on relatively affordable prosumer technology. I know nothing about the power side of lasers and imagine you'd need a decent size truck to hold one capable of setting something on fire at distance and its power supply, but it doesn't seem beyond the bounds of feasibility. Of course, it would be 'easier' to hijack the balloon's guidance system but I assume that about 5 minutes after you started broadcasting on restricted radio frequencies people would be looking for you.

mirimir 7y ago
OK. But small balloons at 15-20 km? That don't reflect much light? Seems iffy to me. But maybe so. I wasn't thinking of massive physical damage. Just nuking the FPAs. Or perhaps small rockets. But guidance systems are hugely illegal to develop. Chaff might work to mask movements temporarily. Or wildfires, I suppose. Not that anyone sane would do that.
- mgamache 7y ago
  "guidance systems are hugely illegal to develop" Curious what laws cover this? I am sure they exist, just not explored this at all. Isn't GPS a 'guidance system'?
  - mirimir 7y ago
    I've seen reference in a few articles about model rocketry.
  - pintxo 7y ago
    > The U.S. government controls the export of some civilian receivers. All GPS receivers capable of functioning above 18 km (59,000 ft) above sea level and 515 m/s (1,000 kn; 2,000 km/h; 1,000 mph), or designed or modified for use with unmanned missiles and aircraft, are classified as munitions (weapons)—which means they require State Department export licenses. [1] [1] https://en.wikipedia.org/wiki/Global_Positioning_System#Restrictions_on_civilian_use https://en.wikipedia.org/wiki/Global_Positioning_System#Rest...

craftinator 7y ago

High velocity, heavy caliber hunting right with accentuated rifling, attached to a heavy servo gimble or robotic arm, telescopic lens, laser range finder. Should be able to shoot these down all day long.

mirimir 7y ago
A hunting rifle can reach 10-15 km altitude?
- galangalalgol 7y ago
  not even close, and none of this is civil disobedience. civil would be to have a movement put multispectral bright lights on top of every car boat plane train bicycle ball cap dog collar and then scatter them everywhere at intersections and parks etc. not sure how bright they would need to be to saturate enough to hide the car or dog. you could track the bright spot till they intersect but then I would be iffy to keep them apart at slow intersections I think.
  - mirimir 7y ago
    This is a great idea! Prices of bright LEDs have dropped considerably in recent years. So it wouldn't require that much energy. With enough bright spots, scatter would complicate tracking anything specific. Also, that'd provide cover for the occasional targeted high-energy laser pulse.

raxxorrax 7y ago

It is easier to find the control room and drop the pants of operators.

dredmorbius 7y ago

Blinding sensors, disabling transmitters (beamed energy / emp burst?), disrupting transmissions, or disabling the platform itself (balloon) would be the most obvious choices. Legal challenges.

ptero 7y ago

Location and targeting are trivial (as others said balloons will likely have ADS-B or similar transponders). But your laser (prep and action) will be super easy to detect, too.