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Inventor to Launch Pop Bottle Rocket into Space
DrButts writes "An inventor in British Columbia wants to be the first to launch a pop bottle rocket into space. 'This could be impossible, but the CEO of AntiGravity Research already holds the altitude record for boosting an elongated plastic pop bottle — propelled by a bicycle pump, water and a bit of soap — into the air. Firing the ubiquitous, two-litre plastic container usually consigned to the recycle bin into space might create a whole new definition for space junk, but the dream keeps Schellenberg going.'"
Only 79.8 km (out of 80...) left to go, if you take the lowest recognized definition of outer space.
Isn't it "sine qua non," or have I been using the phrase incorrectly my entire life? A quick search for "sin qua non" leads to nothing but "sine" versions of it.
If you dropped a pop bottle onto Earth from a great height, say a million miles, it would splat (air resistance excluded) at about 25,000 MPH. Seven miles per second. Analogously, if you wanted to reverse the course of the pop bottle, you'd have to launch it from the Earth's surface at a similar speed. Now IIRC at about Mach 1.5, aluminum begins to soften. I suspect the plastic in a pop bottle melts at a somewhat lower temperature. So even if you could get enough dry ice or Mentos to launch the bottle at seven miles per second, it would probably melt in about two seconds. Not to mention that air resistance would slow it down considerably on its upward journey, so it's unlikely to have enough speed for the long run.
To actually achieve orbit, not only does it need to reach this altitude, but also move horizontally at probably over 20,000 miles per hours once it gets there.
"I have never let my schooling interfere with my education." - Mark Twain
Has he even broken Mach 1 yet?
There's actually not much in the way of a rule that says something going into orbit has to reach 'escape velocity'.
That's a barrier for barking huge spacecraft, but if you went slowly, and gradually kept up the acceleration, you'd get into space, and with a little assistance from Earth's own gravitational well you could slingshot out and away into interplanetary space.
We don't dump our satellites in your recycling bin, please don't shoot your pop bottles into our space.
Nah, putting them in the recyling bin would be far too orderly, NASA has the military shoot them down with missiles and lets God sort out where the pieces end up.
Maybe we should combine our desires and use pop bottles to take out your failing satellites. Of course then the military doesn't get to use their toys... so that won't work.
You're calculating the speed it would need to start at if all thrust were exerted at ground level and it had to coast up to space (again excluding air resistance). If on the other hand you apply thrust throughout the flight, space can be achieved without ever approaching 25,000 MPH. For instance, Space Ship One never flew 25,000 MPH yet it made it to space.
Also note that I don't believe he'll make it either, and I've always considered 80km to not really be space flight. Just pointing out that the facts you mentioned won't necessarily be the ones that stop the adventure.
He's getting rather old, but he's a good mouse.
The guy's web site. I did a google search on "Mr Widget" bottle rocket and the results were all from news sites to do with this story. Searching on antigravity research was better.
Loose lips lose spit.
No, but you have to get almost there. Low Earth Orbit is 7.8km/s, escape velocity is 11.2km/s. In addition, any non-escape ballistic trajectory that starts from the earth will form an ellipse that will eventually intersect the earth, meaning your rocket must accelerate sideways a fair bit once it's up there.
You need much less speed to merely reach space and fall back down, but the article clearly said 'orbit'.
Um, not quite. Admittedly, if you had a very high lift wing (or a big balloon) you could make it to the upper atmosphere that way, but once past the atmosphere at some point you would have to get to orbital velocity, well in excess of Mach 1 at ground level (past the atmosphere Mach numbers have no meaning). A rocket has a fixed delta v which it has to expend to get where it's going, the more of it that it expends to cancel gravitational acceleration the more fuel is wasted. Once in a reasonably high orbit, one could use a slow thrust method like a solar sail to get out of the gravity well.
As for an unpowered slingshot assist, totally impossible. Slingshot assists operate by following a trajectory from outside the gravity well, into it, transferring a bit of the momentum of the planet to the spacecraft.
They did not worship the bottle that fell from the sky. Being the hardest substance ever encountered by them (glass) and having a whole host of uses, it introduced the concept of possessions, envy, and subsequently violence to their society. The people decided it was an evil thing and their leader took it to the end of the earth (a massive cliff) and threw it off.
It is by the juice of the coffee bean that thoughts acquire speed, the teeth acquire stains. The stains become a warning
Impossible. It took about sixty to lift Kari.
Les Miserables Volume 1 now up with my reading of
The first space trips (even those by manned capsules) were suborbital flights (not a stable orbit)
Wouldn't filling the bottle with hydrogen peroxide under pressure and expanded and then using some for of catalyst like Nickel to react with the peroxide work just effectively?
I know theory and practice often make fun of each other, but I would think that he could use the same type of metrics but with a soft bladder or something separating the peroxide from the catalyst and held in place by pumping the pressure on the opposite side to equalize the effects of the peroxide. Liquid isn't really compressible but the bottle's expansion could be the pressure point. And once it is launched by traditional air or air-liquid launch, the pressure drops on one side allowing the peroxide to flow through then the heat generation could and pressure would hold it back but still allowing it to expand as it hits the catalyst and effectively creating a rocket engine.
I don't know how much pressure could be harnessed this way but it is essentially the same concept of a jet pack. Except the weight to thrust ratio would be extremely different. You could end up with 4 or 5 pounds of fuel to a quarter pound object or to put it more excitingly, some older jetpacks or rocket belts generate about 185 lbs 280-300 lbs of thrust for over 21 seconds. In contrast and using some number conversions for impressively big numbers, that could be around 4800 onces of thrust for a 4-12 once object before fuel weight.
Of course I could be off here a bit, and I don't know how to translate thrust and burn time to distance covered. I suspect that has to do a lot with the total weight and some way to account for the loss from fuel spent and specific thrust sizes and pulses and all that jazz. And I'm also not sure if this type of fuel would be effective at altitude. And while this isn't technically burning, it might not be what he is looking for.
Considering that things like nitrogen and oxygen molecules have trouble staying together at that height what makes you think a cloud of hydrazine, which is highly reactive and thermally decomposes at o K, would survive long enough to precipate out over, "several hundred square miles"? Would ~454kg (1,000 lbs.) of hydrazine even be toxic spread over an area of that size?
But when you finally got into space, you'd be (very nearly) moving at escape velocity. That's how we define escape velocity, after all: it's the speed required to overcome the earth's gravitational attraction. The difference between your actual speed and escape velocity will be negligible once you're far enough away, but you have to get there or you can't escape. It's easy to show mathematically.
Legalize it.
The Kármán line. I was just reading about it last week. The air is so thin at 100 km than an airplane would have to travel at a speed greater than orbital velocity in order to generate sufficient lift, and if it's traveling that fast, it doesn't need lift.
fixed link: http://en.wikipedia.org/wiki/K%C3%A1rm%C3%A1n_line