# Artificial Meteor Shower

• September 27th, 2017, 11:26 AM
JoeinCT
Artificial Meteor Shower
Take a shotgun and various shells to the ISS. The shells would be filled with various sizes and materials, copper, nickle, strontium, and calcium to name a few. Go outside, point the gun at earth and fire. Wouldn't the shot produce a spectacular, if brief, pseudo meteor shower? Would the various materials produce colored showers?
• September 27th, 2017, 02:46 PM
Genesis
Why not, faint burn outs sounds good to me. Mind you a shot gun on the space station. Not going to happen
• September 27th, 2017, 05:18 PM
Dywyddyr
Quote:

Originally Posted by Genesis
Mind you a shot gun on the space station. Not going to happen

If the Russians can fit a 23mm cannon on one of their satellites I don't see why a shotgun is hard to do.
• September 27th, 2017, 07:19 PM
Falconer360
Also didn't the Russians used to pack shotguns with their cosmonauts on their space missions?
• September 27th, 2017, 09:24 PM
Janus
A shot gun won't do it. A typical muzzle velocity for one is ~37m/s. It would take a delta v of ~87 m/s per sec just to get the pellets to upper limit of the Mesosphere( where most meteors appear). In order to get the pellets to enter the atmosphere, you have to remove enough of the 7.6 km/sec orbital velocity of the ISS to allow their new trajectory to enter the upper atmosphere.
• September 27th, 2017, 10:48 PM
JoeinCT
Quote:

Originally Posted by Janus
A typical muzzle velocity for one is ~37m/s.

I think your figure for the muzzle velocity is off by a factor of ten. Shotgun muzzle velocities are ca. 1200 fps.(366 mps). 37 m/s equals 121 fps.

They can go as high as 1600 fps. (487 m/s. See Wikipedia Shotgun entry.
• September 27th, 2017, 10:50 PM
Dywyddyr
Quote:

Originally Posted by Janus
A shot gun won't do it. A typical muzzle velocity for one is ~37m/s.

Conversion glitch?
A typical V0 is ~1200 fps = ~366 m/ sec.
• September 28th, 2017, 09:56 AM
Janus
Quote:

Originally Posted by Dywyddyr
Quote:

Originally Posted by Janus
A shot gun won't do it. A typical muzzle velocity for one is ~37m/s.

Conversion glitch?
A typical V0 is ~1200 fps = ~366 m/ sec.

Yep, somewhere along the way I misplaced my decimal point. So it does looks like a shotgun could de-orbit its shot by enough.
So the next question would be what kind of display would you expect to see?.
One factor to consider is that the pellets are going to hit the atmosphere at a speed that is not too different from the ISS orbital speed (7.6 km/sec) While a typical meteor is traveling at ~20 km/sec. This means, gram for gram, a typical meteor would have ~7 times the kinetic energy to dissipate than a shotgun pellet.
Then we would have to consider the spread of the pellets. A low end spread is ~ 1m per 40m range. If we just take the difference between the ISS altitude 400km and the top of the Mesosphere 100 km as the range, we get a spread of 7.5 km. From someone sitting on the surface of the Earth, this is a spot of ~4.3 degrees wide as the origin for our meteors. However, with orbital mechanics involved, this is probably not going to work out quite this simply. Each pellet, due to its initial spread velocity will be in a slightly different orbital trajectory. And depending on how the shotgun is aimed when fired, this could have a significant effect on the spread upon atmosphere entry.

I'm going to be out and about for most of the rest of today, so I won't be able to sit down and work out the particulars right now. Maybe I'll have some time tomorrow to give it a go.
• September 29th, 2017, 02:17 PM
Janus
Okay. I took some time to crunch the numbers. Assuming a muzzle velocity of 366 m/s and a spread of 1m per 40 m, I get the following answers:
The pellets will take ~866 sec to hit the top of the Mesosphere. They will strike at a fairly shallow angle, on a line ~4.5 degrees long and ~ 1.7 min of arc thick.
They will hit the Mesosphere stretched over a period of just under 1/2 sec.

The pellets will hit at ~7.93 Km/s or ~40% of the average speed of an meteor. They will thus have a bit less than 16% of the energy per gram compared to a meteor. The power needed to overcome drag increases by the cube of the velocity, so these pellets would dissipate energy ~6.4% the rate per gram of a typical meteor. Less energy to begin with, radiated away 6.4% as fast, might not lead to a very significant display, and considering the mass of shot gun pellets, might not even be naked-eye visible from the surface.
• May 7th, 2018, 10:54 PM
doitright
Dust particles are seen from the ground. As is satellite debris. The bigger the particle, and the more cohesive strength they have the grighter and longer they last and the longer the streak they make. The heat of the particle causes it to glow brightly white. Vaporized material is hot enough to ionize and produces a color but the atmosphere also ionizes and makes more light than the relatively small amount of ionized meteor material. That light is green because of the hydrogen and helium in the upper atmosphere. The size and material of the shot would have more effect on the display. Lead bird shot would make more shorter streaks than double 0 shot. Rock salt shot with large chunks with low cohesive strength would make short streaks and explode at the end.