If an astronaut fired a shotgun at Earth from orbit....

[Aldebaran]

That plus the 1700 mph of an actual bullet is still short of 25,000 mph to 160,000 mph for a shooting star.

Not really. A meteor (sometimes called a shooting star) is actually any object that falls into the atmosphere. Some of it is debris from rocket launches (scrap metal, flecks of paint, etc) that ended up in orbit and eventually fell out of orbit. So those items would still only be doing about the 17,000 MPH required to be in orbit.

 

[timothyu]

Not really. A meteor (sometimes called a shooting star) is actually any object that falls into the atmosphere. Some of it is debris from rocket launches (scrap metal, flecks of paint, etc) that ended up in orbit and eventually fell out of orbit. So those items would still only be doing about the 17,000 MPH required to be in orbit.

True but does not light intensity (dull red glow to brilliant white light) relate to speed?

 

[durangodawood]

Just make sure you are over Texas, then you are covered.

They think they own the sky.

 

[timothyu]

They think they own the sky.

Doctor Who protects us.. even from ourselves.

 

[Aldebaran]

True but does not light intensity (dull red glow to brilliant white light) relate to speed?

It might. I know colors have to do with what the material burning up is. As for how bright, I don't know.

 

[timothyu]

As for how bright, I don't know.

Consider rocket stove compared to fireplace.

 

[Aldebaran]

Here's an even better idea than using a shotgun shell with less than 400 pellets:

Consider again that most meteors are the size of a grain of sand....

What if NASA hoisted a 5 gallon bucket full of sand up into orbit and then dropped into the atmosphere at the 17,000 MPH orbital speed? Upon entering the atmosphere, the bucket would burst open and about a billion grains of sand would quickly spread out and burn up. Even better if NASA would install a small explosive charge within the bucket to be detonated just before the bucket entered the atmosphere, which would disperse that billion grains of sand over a much larger area before they re-entered. The sky would light up with a billion little meteors, making an observer think the world was ending!

Then again, that explosive device would also send millions of sand grains into all levels of orbit as well, creating millions more little collision hazards for astronauts, the ISS and satellites for a very long time. But hey! It would be a sweet little light show for observers on the ground!

 

[timothyu]

There is enough pollution out there already methinks. And it gives new meaning to 'the sky is falling'.

 

[jayem]

Isn't it possible that pellets fired by an astronaut, who's orbiting the Earth, would also go into orbit? IIRC, the space shuttle orbits at about 220 miles up. It's still in the Earth's gravitational field, but it travels at a forward velocity that equals gravitational attraction at its altitude. The result is that it orbits the Earth, rather than falling. In fact, the shuttle returns to earth by firing its engine to slow it's velocity, which causes it to fall out of orbit. Shotgun pellets have a tiny fraction of the mass of a space vehicle. According to Newton's law, gravitational attraction is directly proportional to mass. (And inversely proportional to distance squared.) So even if they're fired straight down towards Earth, with their low mass, they still might have enough forward velocity to stay in orbit. At least for a while. To see them burn up might require they be fired at a lower altitude. Does this make sense?

 

[Aldebaran]

Isn't it possible that pellets fired by an astronaut, who's orbiting the Earth, would also go into orbit? IIRC, the space shuttle orbits at about 220 miles up. It's still in the Earth's gravitational field, but it travels at a forward velocity that equals gravitational attraction at its altitude. The result is that it orbits the Earth, rather than falling. In fact, the shuttle returns to earth by firing its engine to slow it's velocity, which causes it to fall out of orbit. Shotgun pellets have a tiny fraction of the mass of a space vehicle. According to Newton's law, gravitational attraction is directly proportional to mass. (And inversely proportional to distance squared.) So even if they're fired straight down towards Earth, with their low mass, they still might have enough forward velocity to stay in orbit. At least for a while. To see them burn up might require they be fired at a lower altitude. Does this make sense?

It does. One solution could be to fire the shotgun in the opposite direction of the orbit. That would make the pellets orbit at about 1,600FPS slower than the astronaut and whatever vehicle his is with. Converting FPS to MPH, 1600 FPS is the same as 1,091 MPH. So firing the shotgun "backwards" into the orbit, which is roughly 17,000 MPH, the pellets would be now going "only" 15,909 MPH. The pellets would fall toward Earth, although probably not all that fast. By the time they did, they'd probably be spread out quite a bit.

 

[Astrophile]

In a low earth orbit the shot will already be moving at 17,000 miles per hour before even being fired.

If the astronaut was in a circular orbit at 17,000 mph (7.6 km/s), the shot would move in a slightly elliptical orbit at essentially the same height as the astronaut, rather than entering the atmosphere and producing a meteor shower.

 

[Ophiolite]

If the astronaut was in a circular orbit at 17,000 mph (7.6 km/s), the shot would move in a slightly elliptical orbit at essentially the same height as the astronaut, rather than entering the atmosphere and producing a meteor shower.

Finally! Thank you.