A Cannon for Shooting Supplies into Space

"John Hunter wants to shoot stuff into space
with a 3,600-foot gun. And he’s dead serious—
he’s done the math. Making deliveries to an
orbital outpost on a rocket costs $5,000 per
pound, but using a space gun would cost just
$250 per pound."

See:

http://www.popsci.com/technology/art...supplies-space

wrote:
"John Hunter wants to shoot stuff into space
with a 3,600-foot gun. And he’s dead serious—
he’s done the math. Making deliveries to an
orbital outpost on a rocket costs $5,000 per
pound, but using a space gun would cost just
$250 per pound."

See:

http://www.popsci.com/technology/art...supplies-space

"the projectile shoots out of the gun at 13,000 mph."

Seems a tad slow.

Sylvia.

Sylvia Else wrote:
wrote:
"John Hunter wants to shoot stuff into space with a 3,600-foot
gun. And he?s dead serious? he?s done the math. Making deliveries
to an orbital outpost on a rocket costs $5,000 per pound, but
using a space gun would cost just $250 per pound."
See:

http://www.popsci.com/technology/art...supplies-space

"the projectile shoots out of the gun at 13,000 mph."

Seems a tad slow.

If you wade through the comments section, someone claims to have
watched a video pitch Hunter made to Google, where it was discussed
that the projective would be multiple stage. Still seems a bit "paper
rocket" to this peanut gallery type.

rick jones
--
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where do you want to be today?
these opinions are mine, all mine; HP might not want them anyway...
feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...

Rick Jones wrote:
Sylvia Else wrote:
wrote:
"John Hunter wants to shoot stuff into space with a 3,600-foot
gun. And he?s dead serious? he?s done the math. Making deliveries
to an orbital outpost on a rocket costs $5,000 per pound, but
using a space gun would cost just $250 per pound."
See:

http://www.popsci.com/technology/art...supplies-space

"the projectile shoots out of the gun at 13,000 mph."

Seems a tad slow.

If you wade through the comments section, someone claims to have
watched a video pitch Hunter made to Google, where it was discussed
that the projective would be multiple stage. Still seems a bit "paper
rocket" to this peanut gallery type.

Well, if the projectile is more than just the payload, then you're back
to throwing away valuable hardware, which would have to make the launch
cost estimates suspect.

Sylvia.

Pat Flannery wrote:
Sylvia Else wrote:
"the projectile shoots out of the gun at 13,000 mph."

Seems a tad slow.

The projectile may have an internal rocket to get the last 5,000 mph of
orbital velocity. Gerald Bull's "Martlet" gun-launched satellites were
intended to use a rocket motor in the projectile:
http://en.wikipedia.org/wiki/Project_HARP

Pat

It occurred to me later that such a system would have to have some
delta-v capability in the projectile anyway, because you cannot put
something into orbit by throwing it from the surface of the Earth.

Sylvia.

Pat Flannery wrote:
Sylvia Else wrote:
Well, if the projectile is more than just the payload, then you're
back to throwing away valuable hardware, which would have to make the
launch cost estimates suspect.

I'm pretty sure if you just fire it directly into orbit without changing
its orbit at some point via a rocket, its eliptical orbit is going to
have a perigee at sea level.

If you fire it horizontally, it would. Fire it at any other angle, and
its (unreachable) perigee is below the surface.

Sylvia.

wrote:
"John Hunter wants to shoot stuff into space
with a 3,600-foot gun. And he’s dead serious—
he’s done the math. Making deliveries to an
orbital outpost on a rocket costs $5,000 per
pound, but using a space gun would cost just
$250 per pound."

See:

http://www.popsci.com/technology/art...supplies-space

Well, at least he came up with a novel means of supporting it by
submerging it in the ocean.
Currents at different depths and storms could be real problems though.

Pat

Sylvia Else wrote:
"the projectile shoots out of the gun at 13,000 mph."

Seems a tad slow.

The projectile may have an internal rocket to get the last 5,000 mph of
orbital velocity. Gerald Bull's "Martlet" gun-launched satellites were
intended to use a rocket motor in the projectile:
http://en.wikipedia.org/wiki/Project_HARP

Pat

Sylvia Else wrote:
Well, if the projectile is more than just the payload, then you're back
to throwing away valuable hardware, which would have to make the launch
cost estimates suspect.

I'm pretty sure if you just fire it directly into orbit without changing
its orbit at some point via a rocket, its eliptical orbit is going to
have a perigee at sea level.

Pat

"Sylvia Else" wrote in message
...
wrote:
"John Hunter wants to shoot stuff into space
with a 3,600-foot gun. And he’s dead serious—
he’s done the math. Making deliveries to an
orbital outpost on a rocket costs $5,000 per
pound, but using a space gun would cost just
$250 per pound."

See:

http://www.popsci.com/technology/art...supplies-space

"the projectile shoots out of the gun at 13,000 mph."

Seems a tad slow.

You'd likely need a couple of solid stages to actually go into orbit. One
to get up to orbital speeds, and one to circularize the orbit.

This isn't something that violates physics, but it's likely that you're
going to need *A LOT* of R&D to make this work reliably. That and you can't
launch much more than really durable cargo with this thing (e.g. food,
water, LOX, LN2, LH3, and etc.).

Jeff
--
"Take heart amid the deepening gloom
that your dog is finally getting enough cheese" - Deteriorata - National
Lampoon