Power Limits of Advanced Propulsion

Phobos · 2002-06-26 18:30:29

I could stand some convincing about NERVA. But if anyone ever proposed using a nuclear Orion system for Earth launches, you would find me among the protestors chained to the launch pad.

Briefly exciting, but they won't find much of you -or the launch pad!

Well hopefully the people at the controls wouldn't press the launch button with people chained to the rocket!

Personally I don't like the idea of using nuclear pulse propulsion from the surface of the Earth either. I do like that idea of using a tether though to lift a nuclear rocket up into a safe area above Earth. With properly encapsulated nuclear explosives there'd be very little danger of nuclear material being leaked into the environment if the tether were to snap. You wouldn't have to worry about a chemical rocket exploding and potentially spreading all of those little bomblets all over the Atlantic.

John_Frazer · 2002-07-11 20:31:54

"Phobos" wrote:

... I do like that idea of using a tether though
to lift a nuclear rocket up into a safe area
above Earth. With properly encapsulated
nuclear explosives there'd be very little danger
of nuclear material being leaked into the
environment if the tether were to snap.

Or nuclear or solar thermal. whatever works (ED tethers are nice because they're a workable version of "magic" propulsion -no propellant mass being thrown backwards!)

I'm not entirely sure we understand each other in mentioning tethers.
First, you cannot use tethers to lift 100 tons, or even 20 tons from the ground... We still are stuck with chemical rockets for that. I doubt ED tethers are even strong enough (with reasonable mass/thrust ratios) to lift from a sub-orbital trajectory before it re-enters on the other side. (If a first stage gets something to orbital height, but not quite enough velocity, then 1/2 orbit later the perigee will be too low, and you lose it. A spinning tether can exchange orbital velocity with a comparatively much smaller load, raising the load's perigee above the atmosphere.)
A momentum exchange tether station could concievably do it in one throw, but if you can build, launch, and operate one capable of lifting a 20, 100, or 500+ ton load from a hypersonic suborbital trajectory to a high orbit above the magnetosphere, then you don't need anything else, because you can work miracles.
You must get your load into LEO, and extend solar panels or fire up a nuclear plant to power the ED tether, for a gradual boost, probably taking days.

You wouldn't have to worry about a chemical
rocket exploding and potentially spreading all of
those little bomblets all over the Atlantic.

Forget about vaporizing the bomb pits, even in a worst-case accident. If the packaging split, spilling the bomb pits or complete pulse units, they'd fall harmlessly to the bottom of the ocean (they are extremely dense, well built objects, and they wouldn't be broken up in a typical launch accident)
If it's a one-HLV launch, with the NPR engine being fired at the top of an arc, the bomb pits are in the middle of a 580 ton chunk of ship, so they'd be recovered intact from the wreckage at the bottom of the ocean. We'll package them to survive if they're cargo on a booster (in the case of a multiple HLV boosted, LEO constructed ship.

Sure, we have examples of RTGs burning up and spreading radioactive debris. I'll argue that they weren't designed properly...
These were not launch accidents, but re-entering satellites. By definition, a booster acident involves much less energy, and properly designed RTGs would be intact at the bottom of a hole in the ground, even if falling from orbit. (Yes, a booster malfunction involves lots of energy, but very little of the energy of a rapidly burning cloud of rocket fuel goes into the payload. Comparatively, falling from orbit is more stressful...)
Anything threatened by radioactive leakage would already be crushed by this dense mass falling from the sky!
A water tank from Skylab survived orbital re-entry mostly intact.
The crew of the Challenger survived the booster malfunction and vehicle breakup. They fell for 2.5 minutes, and the impact with the ocean is what killed them (no parachutes, airbags, or basically any kind of survival possibility on the Shuttle).
Hitting the water is something a properly designed container could survive. (Especially if we launched the pits in a recoverable "escape module" with parachutes, airbags, or the sort. Plutonium is valuable enough to go to the effort.) Booster malfunction, fuel mass-combustion, range safety charges, and all, we could ensure the safe recovery of the bombs (easier than people!).

An Ares boosts 120 tons to LEO, or ~65 tons without the second stage. The 2SSME variant of the Shuttle-C is the cheapest, nearest term HLV we could get, and it lifts ~40 tons, so that means 20+ tons of protective packaging for the bomb pits.

John_Frazer · 2002-07-11 20:41:50

I wrote:

Somebody mentioned fusion only (nuclear explosives).
We've got to convince the DOD to declassify some
of their new R&D for such things. If we could
guarantee that there are no long-lived isotopes
-or short lived but highly radioactive ones which
may be worse-, would it be such a problem?

There's some debate over whether this is possible today. I don't pretend to know, but it is interesting.
Somebody once suggested neutron bombs to me: No or very little lingering radioactivity or fallout sounds like exactly what we need. The prompt pulse of neutrons from a 84km altitude string of blasts of only .1kt ech, over the middle of the ocean coudn't hurt anything. Eliminate the enhanced neutrons, but keep the "clean" nature, and we're more than halfway there. Eliminate the gamma rays, and what little fear of EMP there is from such a tiny blast also disappears.

Take these to the extreme, and maybe a Big One could be ground launched.(?) That's a dream-prospect: 10,000 tons at liftoff, more than 50% of that being cargo to Mars on a trip of less than 2 months...

If you can't accept the possibility of making
clean bombs, or even the acceptabillity of such
zero-impact launches politically (if possible),
then there's always the hard way. 5-6 Ares
or Energia launches does it.

Lift the parts to LEO to be assembled. I like the ability NPR gives to mission designers to build parts massively. Think of a typical merchant ship -if not a battleship- rather than a fragile aerospace construction. Simple, dumb connections could hopefully eliminate much of the difficulty of EVA assembly work.

Send the Pu pits for the pulse units (bombs)
up in a separate launch, with tremendous care
taken to preserve & protect the Pu in case of a
launch accident...If the booster malfunctions,
the Pu itself is preserved as well as a crew
would be!

The version of the Shuttle-C with 2 SSMEs on the cargo pod is arguably the cheapest near-term booster we could get. It puts ~40 tons into LEO. This allows for some pretty robust packaging. If this isn't enough, the Ares puts ~120 tons into LEO, or ~65 without the upper stage.
I think we can practically guarantee that the plutonium bomb pits could survive, and be readily recovered.

Use ED tethers or something to lift the apogee
above the Van Allen belts before the NPR
engine is fired.

This points out another way that the immense capability of NPR simplifies things: You don't need to scrimp propulsive effect by firing the NPR engine at perigee (the closest approach to Earth) for the best effect. Go ahead and fire it off while at the weak, lowest velocity (highest altitude) portion of your elliptical orbit.
Really, the performance available from this engine changes your way of thinking about spaceflight.

the propellant to be vaporised by the blast and
directed at the ship's pusher plate is ~90% of the
mass of the pulse units.

This from a quote from Dyson, while discussing water resources in space. The (rough) figure of 45% of the IMLEO being cargo at Mars doesn't include this capability. Eliminate 90% of the mass of the return delta-V "bombs", and fill up with Diemos water, CH4, NH3, or whatever ices are most handy (It arguably being easier to get at such resources at Diemos than on Mars itself)

Phobos · 2002-07-12 00:32:07

I'm not entirely sure we understand each other in mentioning tethers.
First, you cannot use tethers to lift 100 tons, or even 20 tons from the ground... We still are stuck with chemical rockets for that. I doubt ED tethers are even strong enough (with reasonable mass/thrust ratios) to lift from a sub-orbital trajectory before it re-enters on the other side. (If a first stage gets something to orbital height, but not quite enough velocity, then 1/2 orbit later the perigee will be too low, and you lose it. A spinning tether can exchange orbital velocity with a comparatively much smaller load, raising the load's perigee above the atmosphere.)

My motivation for building the nuclear spacecraft was more for speed than for lifting capability. I was thinking we could use tethers to lift a nuclear spacecraft into orbit. Or if we couldn't lift the whole thing at once (which makes a lot more sense now that you mention it ) we could use tethers to lift its parts and assemble them in orbit. Really though, it's a shame that we can't use Orion style spacecraft to lift payloads into space. Going to the moon or Mars would be way cheaper kilogram for kilogram with an Orion than half-baked chemical rockets. Why does the best stuff always have to be so damn forbidden and hazardous?

Tyr · 2002-09-18 15:18:50

these links might help

http://roadrunner.com/~mrpbar/rocket.html

http://www.astronautix.com/engines/rd600.htm

sethmckiness · 2002-09-24 14:07:24

While it is a lot less weight then talked about a B-1B Lancer could carry in excess of 20,000 Kg to over 50,000ft up to or in excess of Mach 1

A C-5 Can carry atleast 270,000 lbs to atleast 40,000 ft approaching Mach .77

This could theoretically save on same energy requirments, but something like a B-70 would need to be used to get any true benefit, It was capable of flying in excess of 70,000 ft with over 50,000 lbs at over Mach 3. (again weight may not be enough to prove useful. This plane was designed in the 1950's so I imagine it would be possible to have a plane that goes in excess of Mach 1 at over 70,000 feet lifting well over 100,000 lbs that could prove as a somewhat efficient reusable first stage...

Also, any good books that I could read to get myself up to speed on Orbital Mechanics?

thanks

TJohn · 2002-09-25 06:10:15

Check this site out and tell me what you think about it.

http://www.stardrivedevice.com

If it is a good as it states, we could get to interstellar space in no time.

Shaun Barrett · 2002-09-26 01:43:21

Hello TJohn!
The author of your starship book is evidently familiar with much of the latest conjecture in physics. His terminology has enough of the 'buzz words' in it to sound like genuine tech-talk, but my impression is that he's selling generalisations and notions with a few equations thrown in as seasoning.
He seems to think that if his craft can approach very close to light-speed( a mighty big IF !! ), its relativistic mass will climb past the Chandrasekhar limit of 1.4 solar masses and that, somehow, this will create a warp in space. As far as I can tell, the craft is presumed safe from the fate of effectively disappearing up its own fundamental orifice, as long as Lorentzian contraction doesn't reduce its line-of-travel dimension to the Schwarzschild radius for a body of that mass! (He cheerfully skirts around the fact that his vessel is not a sphere, so it doesn't really have a meaningful radius for these purposes, by emphasising that everything he says is only a rough approximation - "largely illustrative and instructional in nature")
He claims he's been given a patent for this contraption. I'm not sure what that really means. If a patent is granted, does it mean people with sufficient background in this kind of physics have checked out the mathematics and found it to be legitimate?
The bottom line is, I strongly suspect it's all hogwash! But if someone out there with the right tools for the job can confirm that suspicion, I'd be interested to hear from them. And I guess TJohn would be too!

TJohn · 2002-09-27 11:39:45

I found another site. This one may have been posted before joining.

http://www.androidspub.com

They even go as far as accepting reservations for the first trip!

space_psibrain · 2002-09-29 23:40:16

There is a little known technology called the Inertial Drive, which converts the angular momentum of splitting matter into forward thrust. It requires no fuel, merely electrical energy, is capable of huge thrust output, and can lift itself off of earth. The technology was demonstrated to companies such as Boeing in the year 1999, and they are considering whether or not to acquire the technology from the inventor.

Phobos · 2002-09-30 20:30:22

There is a little known technology called the Inertial Drive, which converts the angular momentum of splitting matter into forward thrust. It requires no fuel, merely electrical energy, is capable of huge thrust output, and can lift itself off of earth.

Maybe I'm misunderstanding something, but if the inertial drive breaks apart matter to create thrust, wouldn't it need to carry some kind of "fuel" to break apart with electrical energy? Or would it be able to just suck in air and break that apart?

space_psibrain · 2002-10-01 22:30:52

It is known as the CIP, or Cook Inertial Propulsion...look it up. Its actually quite fascinating

nebob2 · 2002-10-08 23:05:11

I think this falls into the "I'll believe it when I see it catigory". Outragous claims like this have been made before, with litrealy thousands of inertial propulsion machines patented. I have a feeling we will be left with chemical boosters for a very long time.

dickbill · 2002-10-09 15:11:34

Hi all,

since chemical boosters still seem the only practical solution to send important mass into orbit, what about the recent advances in chemical propellant ? Is there no promissing advances possibles ?

Is the couple H2/O2 cryogenic or H2/O2 atmospheric still the best combination for specific impulsion ?
What about heavier highly unstable, semi fissile, molecules encaged into carbon cage buckminsterfullerenes, like polyanion/cation Uranium complex, which could oxydize/detonate and partly go into a chemically drive fission reaction. It would be nice to add the atomic energy to the molecular oxidization. Is there no such molecules synthetized in the purpose to serve at rocket propellant ? I am sure the US have done some research in that area (51) , but maybe it's top secret and restricted to the US air force usage....

Austin Stanley · 2002-10-13 02:51:36

While far out there anti-matter is also an option. With its obscenely high conversion efficency you could use it to heat your propelent far more than any other other option could possibly begin to. However, producing it difficult (and expensive) and contaning it is next to impossible (and very, very expensive). But heck if you want matter to produce you some energy, anti-matter has by far the highest possible returns. Probably the highest possible, if true total conversion of matter is impossible. Of course cost wise, a fusion rocket would probably beat it pants of unless a (much) cheap method if found of producing it.

Another fundemental issue to consider is this. No matter how efficent you engine is. Lifting and accelerating large amounts of matter into orbit requires a set amount of energy. You can change the timeframe on which this is released but you can't change the amount. Anytime you assemble this amount of energy in one place you must also consider the risk that it might accidently go off in a critical manner (ie. all at once). And when you're dealing with such large amounts of energy, you have to be careful that you don't blow the place your launch pad is in off the map.

Also, anytime your dealing with heating a propelent. You also have to find a way to deal with the wasted heat this will build up on your rocket. Unless you want it to melt, which you probably don't. This tends to be the limiting factor for many types of engines (NTR, ect...). If you find a better way to deal with that wast heat you can generaly heat your propelent faster and thus have a higher ISP.

Preston · 2002-10-13 09:56:55

Interstingly enough, there's a rocket that attempts to address a few of the issues in your (Stanley's) post. I think the design is called AIM-star. It's an antimatter initiated fusion rocket, and it uses a storage ring to store the antimatter (so it's in a plasma state, and I would think they need to put positrons in there too, but maybe it's not necessary?). The ring uses magnetic confinement. The heat removal system is interesting. What I've seen for systems like NTR is several 'fins' surrounding the engine that radiate the heat away. In AIM-star, there's a liquid drop radiator. They pump the engine coolant (or transfer the heat to some radiating fluid first) and send it to the front of the ship. Then it's expelled in droplet form along a sort of pipe that's perpendicular to the acceleration of the ship, so that the droplets accelerate to the back of the ship in a sheet-like formation, where they are collected by a similar 'pipe.' They even have quantitative stuff on this.

There's an address for a paper on this rocket, but I checked out Penn State's physics site and it says they're reorganizing stuff. Here's the link anyway in case it starts working:
http://antimatter.phys.psu.edu/Papers/AIMStar_99.pdf

John_Frazer · 2002-10-23 00:41:19

While far out there anti-matter is also an option... However, producing it difficult (and expensive) and contaning it is next to impossible (and very, very expensive).

Yes, that Penn St. article covers antimatter pretty well.
Specifically, it's another form of nuclear pulse (Ion beam Compressed ANtimatter, or ICAN is another name), where pico-grams of anti protons are injected into a HEU target to induce micro-fission/fusion via production of neutrons.
The articles state that only a few milligrams of anti protons are needed for the entire mission (~500 tons in LEO puts a few hundred tons to Mars on a 45 day trajectory. ~120 km/sec delta-V!).
The amount of anti protons is entirely within reason; modest improvements in what we do today would make the entire mission's fuel in 1 year, so we only need ~18 month storage (for a 6 month duration mission; increase this by any surface exploration time past 30 days...), and they talk favorably about improvements in Penning traps & storage devices.

... Lifting and accelerating large amounts of matter into orbit requires a set amount of energy. You can change the timeframe on which this is released but you can't change the amount. Anytime you assemble this amount of energy in one place you must also consider the risk that it might accidently go off...all at once...you have to be careful that you don't blow...your launch pad...off the map.
...You also have to find a way to deal with the wasted heat this will build up on your rocket. Unless you want it to melt, which you probably don't...

In any case, it's interplanetary applications where this is used, instead of getting to LEO.

I like the Sea Dragon for lifting things up (an entire ICAN or Orion ship lifted up to where it can fire the nuclear engine, for instance), but the Shuttle-C or Ares works, too.

mauk2 · 2002-12-10 17:22:56

I completely agree with the topic starter on one thing: You can imagine all of the wonderful deep-space drives for getting to Mars you want, but until we can get off the Earth, they are simply fantasies.

So, how do we do that? As has been written in this thread, normal chemical fuels have reached just about the end of their development. Metastable and/or high energy chemicals are WAY out, if ever. The only likely near-term candidate left for a heavy lift booster is the Nuclear Thermal Rocket (NTR).

Now, the NTR is a potent beast indeed. As has been mentioned in this thread, the Isp of an NTR is dependent on the exhaust speed. To get sufficient speed, extremely high temperatures are required, such that even a reactor core of uranium tri-carbide would melt. To get those temperatures with high thrust takes huge power outputs, which is also difficult for a solid core to do.

The solution is to go with a reactor core that is already melted and extract the energy from the core using a radiative process, not a conductive one. That is how a Gas Core Nuclear Reactor (GCNR) works. The huge problem with the GCNR is that the uranium fuel is unconfined, and will leak out the exhaust.

Luckily, some very smart people back in the 60's figured out a way to stop that, by using a fused silica bulb to enclose the fission core.

I have taken the liberty of designing (crudely) a SSTO heavy lift booster, using 7 very powerful GCNR thrusters with LH2 as reaction mass. This launcher design, which I have christened the Liberty Ship, is fully reusable, has the same takeoff mass as a Saturn V, and can deliver 2,000,000 pounds of cargo to LEO per launch.

I have been working on it on the forums at www.nuclearspace.com , and would be pleased if any or all of the smart folks here would come and take a look at it. All nitpicks happily accepted, criticisms carefully considered, and suggestions gleefully incorporated.

The url for the main thread where the folks at Nuclearspace have been chewing on the Liberty Ship is :

http://pub97.ezboard.com/fnuclea....3.topic

See what you think of it!

Phobos · 2002-12-10 20:31:36

I have taken the liberty of designing (crudely) a SSTO heavy lift booster, using 7 very powerful GCNR thrusters with LH2 as reaction mass. This launcher design, which I have christened the Liberty Ship, is fully reusable, has the same takeoff mass as a Saturn V, and can deliver 2,000,000 pounds of cargo to LEO per launch.

I like the idea but what happens if the rocket malfunctions and comes crashing back down to Earth. You can design an RTG to survive a mishap like that but I'm not sure about nuclear propelled rockets. Don't get the idea I'm anti-nuclear but I worry about the safety problems if such a rocket were to explode or even just tip over on the launchpad. I might be overestimating the size of these engines though. Perhaps it would be possible to contain the fuel itself in a mishap like that somehow?

mauk2 · 2002-12-10 23:17:06

phobos: Yes, I have indeed taken fairly extreme measures to ensure the vehicle is safe.

The launch weight is 6 million pounds. The thrusters produce 80 gigawatts of thermal output each, which translates to 1,200,000 pounds of thrust at an Isp of 3060.

First: Since the engines produce 1.2 million pounds of thrust each, we could launch it with only 5 engines. Since we have the POWER OF THE ATOM on our side, the first precaution I take is to add two extra thrusters! What this means is that even if you lose an engine at launch, or two, you can still safely launch the vehicle to orbit. Heck, after the first 60 seconds of flight, when the vehicle is high enough to lay over above the atmosphere, you can lose every engine but one and still make orbit just fine.

Second: The fissile fuel is in the form of a gas. When the fuel is not actually being used, it is stored in an aluminum/boron fuel vault, completely sealed, and that vault is sturdy enough to survive any conceivable re-entry stress.

Third: The actual thruster itself has multiple scram systems, including one that is completely passive. If anything goes wrong, the nuclear reaction is killed/poisoned and the fuel mass is placed into the fuel vault for safekeeping.

Fourth: Once in orbit, the spent radioactive fuel is fired into space, combining an orbital circularization burn with a waste disposal manuever. Given the 30 km/sec velocity of the exhaust gases, the spent fuel can either be shot into interstellar space, or dropped into the Sun.

Fifth: The launch site is a semi-submersible tender ship, and that ship is placed in the US territorial waters of Baker Island. Looking east from Baker Island, there is no land for over 6000 kilometers. The Liberty Ship spends its entire powered flight regime over the deep Pacific. Even if there is a total loss of the entire vehicle, the release of radiation is only equal to twice the inventory released from Chernobyl. Now, that sounds bad, but you have to recall that US nuclear tests in the Pacific in the 50's released inventory equal to hundreds upon hundreds of times the radiation that Chernobyl did, and the mighty Pacific absorbed and diluted it all to undetectability.

So, I think it is plenty safe.

If you have more questions, I ask you humbly to go read the thread I have linked above, and please, nitpick away! The more hostile review the design gets, the better it becomes.

Frankly, I am astonished at how easily the design is coming together, materials problems that I would have sworn were impossible prove to be quite do-able with todays technology.

We are more advanced than we know, folks!

Let's get off this rock!

Shaun Barrett · 2002-12-12 07:02:22

Hi Mauk2!

I haven't gone through your plans properly yet but in principle, if it can be made as safe as you say it can, I think it would have to be the next best thing to Orion.

The idea of having a reusable, 2 million pounds to LEO rocket sounds sweet indeed!

I'd be interested to hear what people like Robert Dyck have to say about it, since they seem to have appropriate expertise in this kind of stuff.
The usual problems with the 'nuclear = leprosy brigade' would arise, of course. But at least now the U.S. has an administration which is prepared to examine all the options - including nuclear.

Thanks for the fascinating idea!

I hope we hear more about it.

mauk2 · 2002-12-12 14:16:53

Thank you for the encouragement, Shaun, and I hope that folks with strong backgrounds in this sort of stuff do indeed go and take a look at it.

I am far from brilliant, and my math skills frankly suck. About the only thing I have going for me is a total lack of comprehension of how impossible this thing is, and a facility with finding oddball solutions to problems.

In other words, BF&MI will carry the day!

So, if there are any scientists, physicists, smart math folks, etc who want to kick holes in my reasoning, please, hit the link above and start poking holes in the design.

Also, a fellow over at www.nuclearspace.com was nice enough to make a cgi of the Liberty Ship, which I have posted at a ghetto webpage. If you want to look at some pictures, try http://www.angelfire.com/space/nuclearmauk2/

Whee!

TJohn · 2002-12-12 16:18:36

I may sound like a little kid, but those are some Awesome pictures!!! Good Job!!

soph · 2002-12-12 17:15:08

mauk, any way to make that horizontally taking off, like an airplane? it would allow us to use already existing facilities, and more often.

mauk2 · 2002-12-12 17:31:50

tjohn: LOL, A picture is worth a thousand words, isn't it? A fellow who goes by "nukepulse" at the nuclearspace forums made the pretty cgi's and they are awesome, indeed.

soph: In the giant thread over at the nuclearspace forums this same question was brought up, and I basically shot the idea down. Sorry.

You see, the empty mass of this launcher is a whopping 800 tons, no runway on Earth could hold the thing up. See, without wings, and with that heavy a mass, it would have to come in for a landing at a HIGH speed, to avoid stalling out. High speed plus huge landing mass = wrecked runway.

The Space Shuttle is tiny compared to this, and it has the highest landing speed of any vehicle on the planet. (I think that's right, the old X-15 had a really high landing speed, too.)

Now, it is possible to try and build it as a flying boat, but again, the speed of touchdown is going to make that problematic.

Instead, I simply put on enough fuel to give the loaded Liberty Ship a total deltaV at takeoff of 15 km/sec. The flight profile I have assumed is to use 10km/sec getting to orbit and dumping the ascent fuel into deep space or the Sun. For the flight back down, 6 or 7 km/sec of velocity is scrubbed using a nice gentle powered aerobraking manuever, and the last 2 or 3 km/sec is supplied by the thrusters as it flies down, tail-first, to land on the launch ship. Please note, that flight profile assumes it has 2,000,000 pounds of cargo going up, AND 2,000,000 pounds of cargo coming back!

If you are willing to run the safety margins during ascent a little thinner, the Liberty Ship could easily place 3,000,000 pounds or more into orbit, and simply fly back empty.

"Impressive, young Skywalker!"

For much more info, go read the thread at the nuclearspace forums. When I have a little time, I plan to neaten up all this info and present it as an article over there, and even if they turn me down, I'll stick it on my ghetto web page.

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#26 2002-06-26 18:30:29

Re: Power Limits of Advanced Propulsion

#27 2002-07-11 20:31:54

Re: Power Limits of Advanced Propulsion

#28 2002-07-11 20:41:50

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#29 2002-07-12 00:32:07

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#30 2002-09-18 15:18:50

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#32 2002-09-25 06:10:15

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#33 2002-09-26 01:43:21

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#34 2002-09-27 11:39:45

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#35 2002-09-29 23:40:16

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#37 2002-10-01 22:30:52

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#38 2002-10-08 23:05:11

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#39 2002-10-09 15:11:34

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#40 2002-10-13 02:51:36

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#41 2002-10-13 09:56:55

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#42 2002-10-23 00:41:19

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#43 2002-12-10 17:22:56

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#44 2002-12-10 20:31:36

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#45 2002-12-10 23:17:06

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#46 2002-12-12 07:02:22

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#47 2002-12-12 14:16:53

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#48 2002-12-12 16:18:36

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#49 2002-12-12 17:15:08

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