Search found 267 matches

by zapkitty
Wed Jun 16, 2010 8:35 pm
Forum: General
Topic: A good Post On the Deepwater Horizon Accident
Replies: 111
Views: 62156

In that case, I would say the contrary is the case. If you can shatter the pipe with explosives so that the silt collapses back onto the pipe, then (a) it will return to as it was before the pipe was there, (b) it is impossible to shatter silt! But the silt is insufficient to contain the blowout, a...
by zapkitty
Wed Jun 16, 2010 11:21 am
Forum: General
Topic: A good Post On the Deepwater Horizon Accident
Replies: 111
Views: 62156

Not exactly my specialty but from what I've gathered from the Oil Drum et al over the past month the sea floor ain't a floor... it's silt for a long way down gradually giving way to a friable rock that will someday become sedimentary rock... when it's had a few more aeons to set. And you have multip...
by zapkitty
Tue Jun 15, 2010 11:05 am
Forum: News
Topic: Elon got his rocket up ...
Replies: 118
Views: 45018

Anything one does to make a sweeper big enough to catch a useful amount of space junk is also going to generate so much drag that it will deorbit itself long before it enough material to be useful. First, anything impacting the sweeper at orbital velocities is going to become plasma and fragments.....
by zapkitty
Sat Jun 12, 2010 7:05 pm
Forum: News
Topic: Elon got his rocket up ...
Replies: 118
Views: 45018

Problem with a cloth sheet for a sweeper is it may become a trampoline. We want to remove the debris, not knock it flying somewhere else. With an impact velocity often measured in kilometers per second that's not going to be a primary design driver. The design driver will be that the "sheet" sheds ...
by zapkitty
Sat Jun 12, 2010 6:48 pm
Forum: News
Topic: Elon got his rocket up ...
Replies: 118
Views: 45018

One could maybe clear some defined orbits, like streets. You would probably still have debris coming in from other orbits though. In fact that's the primary collision geometry. But even a "glancing" blow takes place at orbital velocities... so imagining them as if they were like cars in merging lan...
by zapkitty
Sat Jun 12, 2010 9:22 am
Forum: News
Topic: Elon got his rocket up ...
Replies: 118
Views: 45018

Rearranged the order of your statements a bit... Actually, most LEO space junk is small. Quite true... but this part... Most LEO space junk is things like nuts and washers. ... not quite. Most OD is smaller than 1mm in diameter and consists of solidified metal droplets from explosions and solid rock...
by zapkitty
Fri Jun 11, 2010 8:34 pm
Forum: News
Topic: Elon got his rocket up ...
Replies: 118
Views: 45018

Some fear an orbital debris chain reaction (sort of like fission). http://www.denverpost.com/headlines/ci_5165772 Actually, a Kessler cascade is happening even as we type at each other. Kessler Syndrome does not necessarily posit a single collision that initiates a chain reaction that renders LEO u...
by zapkitty
Fri Jun 11, 2010 6:26 pm
Forum: News
Topic: Elon got his rocket up ...
Replies: 118
Views: 45018

Space junk becomes a problem. If you have people putting up lots of cheap stuff that breaks down the whole time, you get to the point where you'll lose track of it, and where it interferes with most launch trajectories. Actually, doing that would be illegal in most countries. Yes, it's more of that...
by zapkitty
Fri Jun 11, 2010 1:06 pm
Forum: Design
Topic: Using atmosphere as propellant
Replies: 151
Views: 151834

Re: Using atmosphere as propellant

This is true for traditional chemical propulsion, where you have to get to orbit in a hurry before you run out of cryogenic or hydrocarbon propellants. This is not true for a winged Polywell-powered flying machine using relatively small amounts of H and B11 to heat atmosphere as propellant. Propuls...
by zapkitty
Tue Jun 08, 2010 5:30 am
Forum: Implications
Topic: Polywell, ITER and the Helium Supply
Replies: 31
Views: 56248

kcdodd wrote:It is hard to imagine we have so little helium, considering 1/4 of the universe is made of it.
On Earth it tends to migrate up and out when liberated...
by zapkitty
Mon Jun 07, 2010 11:37 pm
Forum: Implications
Topic: Polywell, ITER and the Helium Supply
Replies: 31
Views: 56248

Is there any significant amount of helium available in things like Oil Shale, or the Oil Sands of Canada, where we might be able to recover large amounts of helium from such resources which are mostly un-exploited at present, simply because they are not as cheap as drilling for crude? Don't know of...
by zapkitty
Mon Jun 07, 2010 11:25 pm
Forum: Implications
Topic: Wiffle-Ball as a weapon of terror?
Replies: 16
Views: 28645

kcdodd wrote:How about just an unshielded suitcase x-ray machine.
... but... but... that won't give the powers that be an excuse to place a chokehold on alt fusion research...
by zapkitty
Mon Jun 07, 2010 2:02 am
Forum: General
Topic: In Obama's America we don't Do hard
Replies: 100
Views: 26093

[[Aside: Did you know that there is , in fact, a spare solar array, as well as a spare radiator assembly? They don't have a ride up. If they're needed, and the Shuttle isn't flying, that's just too bad.]] I wondered if that 5th PVR Lockmart et al had listed was a spare ... (eyes radiator speculativ...
by zapkitty
Sun Jun 06, 2010 10:27 am
Forum: Design
Topic: Orbitec's VCCW thrust chamber and Polywell
Replies: 6
Views: 8898

If you're using air augmentation then, while you may use the vortex to keep the plasma from eating your nozzles, you are still going to be moving a lot of air that while hotter than jet exhaust won't be heated to anywhere near plasma temperatures... so could that cooler air be used to cool the nozzl...
by zapkitty
Sat Jun 05, 2010 7:21 pm
Forum: News
Topic: Elon got his rocket up ...
Replies: 118
Views: 45018

SpaceX is already in talks with NASA about super heavy! I read that, but at the time I assumed that it would be "just" the falcon 9 heavy version. Basically two identical booster stages mounted side by side with the core stage. Is the "super heavy" going to be even bigger? In the past Elon Musk has...