Northstar1989

A lot of well thought-out points there, and indeed you're referring to technologies I've never heard of before (such as casaba-howitzer nuclear weapons)... I do persist in saying that space combat would occur mostly at relatively close range, however. One factor you may not have considered is the presence of minefields around important targets such as planets... The economics of mine warfare are extremely good on land, and I can only assume that by the time any major interstellar war might occur, the cost of bringing mass to orbit would have been brought seriously down... You wouldn't have to achieve very dense coverage of the orbits near a planet with mines- their main purpose would be to deter enemies from zipping in and out from around the planet on high-speed strafing runs, like was suggested earlier... If the mine were properly protected from sensors (passive stealth technology), and perhaps given a small but powerful engine to perform last-second boosts at nearby targets ("active" mines) to increase its effective range, you could make it far too dangerous to perform such high-speed tomfoolery... A slower target is easier to hit, and defensive forces would thus be able to seriously deter high-speed strafing runs on the planet's near orbits, while relying on heavily-armed and armored "stationary" defensive platforms (ones with very little engine mass or fuel storage besides a tiny amount for station-keeping) to defend against attacks on the planet... These platforms could be supplemented with drones or a few small unmanned escort-class starships for a low-maintenance defensive solution... (while I believe that in active fleets and invasion forces, manned forces would prove superior; for garrison-type defensive duties, not having to pay salaries is always a much more worthwhile investment). Regards, Northstar

May I point out that you're looking at a laser that has to pass through a mile of seal-level atmosphere? That much air is going to dissipate a LOT of the laser's energy long before it reaches the target. Lasers work much better in space... Also, this was using the electrical systems of a standard, chemical-powered warship. In order for weaponized lasers to ever be truly useful, you would need the kind of power density you get from antimatter reactors... Your assumptions about the size of the craft vs. the size of the target are entirely based on conventional (not even nuclear) power densities. This is a huge mistake, and explains why you think lasers would never work... Regards, Northstar

Ahhh, but the defense systems you just outlines are likely to be complex and expensive. Whereas, efficient lasers are likely to be cheap someday... There are strong countermeasures to almost any conceivable weapons system. The point is to make your opponent spend more time/money/energy defending against just one possible weapons system than it's worth for the majority of his vessels- then he'll only equip a small portion of his ships with anti-laser defenses: which will still leave many vulnerable targets of opportunity... Alternatively, your opponent spends enormous time, money, and effort equipping his entire military with defenses against lasers, whereas you only spend a tiny amount of time/money/effort equipping a handful of your ships with a few lasers in addition to other types of weaponry... Similarly impervious defenses exist against missiles and kinetics. It's not like lasers are the only weapon type with possible effective counters in existence... Regards, Northstar

Just because it's not *CURRENTLY* happening doesn't mean it can't ever happen. You should know better than to make that argument... Yes, computers systems take a LOT of time to initially hack into. But you can prepare "back doors" and sleeper viruses/worms etc. ahead of time, that only activate at the worst possible moment for an enemy (such as on ALL their drone forces in the heat of a battle). Manned ships can easily avoid this possibility by not networking their computers, but unmanned ships don't really have this luxury available to them... Once again, a ship with only a very limited number of heavily-shielded semiconductor chips- not a ship without electricity. Many of the systems you named can easily be run on little besides a steady supply of electricity and analog controls. Life-support, for instance. The main component of that is water electrolysis to produce oxygen. You don't need *ANY* semiconductors to control that- all you need is a steady supply of current (you can perform electrolysis of water in a high school chemistry lab with nothing but a couple electrodes and a current- not computer chips are needed), a series of pressure gauges, and a few switches to adjust the current levels going into the electrolysis system- all of that can be done without computer chips... Rocket Engines can be controlled by just a handful of analog controls- you don't need a computer chip to set the rate of fuel flow into a giant combustion chamber- which is ultimately what determines thrust. Even weapons can easily be run without computer guidance as well. For instance, simple gun-style kinetics. Simply load in a shell, aim the barrel (you don't need to aim very WELL- if you triggered an EMP your unmanned opponents are just floating hunks of metal waiting to be shot to bits...), and trigger the firing mechanism. All of that can be done with valves on hydraulics, switches, etc.. Regards, Northstar

Antimatter production is likely to increase exponentially in future decades. I don't see why we wouldn't have it in three or four centuries. Strong AI faces strong political opposition in some circles which is only likely to grow (and for good reason- we are basically talking about playing god and creating sentient slaves), so I doubt it will ever become a reality except through the work of rogue scientists... True, a spaceship glows like a torch in an asteroid field- but you could easily "fix" that problem by heating up nearby asteroids with some very low-powered lasers. How is the sensor going to tell which is the ship, and which is the asteroid, even if the two (or three, or five...) are a million kilometers apart? Let's just forget this conversation ever happened... KSP is supposed to be a warm, welcoming community... Glad you agree. You can't pack *too many* into a ship. Eventually they start interfering with each other's signals... On top of that, every additional antenna is going to reduce the ship's efficiency and performance... Nukes outdo capacitors, I don't doubt/dispute that. But capacitors are reusable, and can neutralize targets too close to your ship to make use of a nuclear weapon. Additionally, they can also be used for useful energy storage (try harvesting the energy from a thermonuclear warhead, outside of a nuclear pulse rocket like Project Orion...) Regards, Northstar

Who's to say lasers won't be improved in the future? I took a small class taught by a physics professor my freshman year of college who had made his entire research career that- improving the efficiency and cost of lasers. I strongly believe we'll be talking more like 90% efficient lasers some day in the future... Regards, Northstar

I did not say that hydraulics don't need power. Nor did I ever suggest a spaceship running without electricity (both concepts are equally absurd). I said without *electronics*, as in SEMICONDUCTORS- the part most vulnerable to EMP in a ship. There *are* ways to run spaceships without silicon chips. They're not exactly the most efficient, but they certainly work... And, as pointed out, we already have ways to shield electronics. I wasn't speaking of a complete absence of semiconductors either- just a very limited number of very heavily shielded silicon chips, so that a ship could safely run an EMP. Nukes are a great way to generate an EMP, I don't dispute that- I only said they're not strictly necessary- and in some cases are disadvantageous- to take out enemy drones in close proximity to your hull, for instance... Regards, Northstar

A long post, so I'll have to reply piecewise... You're falsely assuming most spacecraft would be equipped with small, extendable omni-directional antenna such as you see on old radios or primitive spacecraft in KSP. Much more likely, any antenna would be a long, winding one built into the hull close to the surface (similar to the built-in antennae on modern cell phones), or a dish-type signal transmitter/receiver. Either one makes a substantial target, and you need only break the winding antenna type in one place to disrupt its transmission ability... Antenna need to be located close to the surface of a spacecraft, as metal will interfere with their signal (read up on a "Gaussian Cage" if you're not familiar- it's impossible to transmit radio signals though a metal shell). Thus, they make highly vulnerable targets, as they can't be protected with thick armor like weapons, engines, or reactors can... The whole point is that your own ship is heavily shielded against EMP (including the sensors), and can have far fewer electronic systems to protect as it is manned (manned ships can make extensive use of valves, hydraulics, and other mechanical control-systems), so you won' lose functions like targeting yourself. It is also assumed that vessels would slow down to comparatively slow attack speeds before engaging their opponents. This is for a variety of reasons, but especially so that if you temporarily lost engine power (due to an enemy railgun barrage, for instance), you wouldn't end up slamming into the nearest planet or hurtling into a nearby star before you could regain control... These slower speeds make manual targeting feasible, even if EMP blew out your targeting systems. EMP doesn't require nuclear explosions. It can easily be delivered by high-powered capacitors. I referred to highly advanced and independent Artificial Intelligence systems that are sentient as quasi-magical (computerized sentience is still a LONG ways away, regardless of what Science Fiction tells you...), not to the ship's drives... Additionally, see what I said about "slowing to attack speed" before- manual targeting would be entirely feasible in many engagements... Plus, I've said this repeatedly- your own ship would be protected against EMP. That's the very reason you would go with a manned ship instead of an unmanned one in the first place- so you had fewer electronic systems to protect in the first place (no computer brain, and many control systems could work on valves and hydraulics- as those on real life spacecraft sometimes do...) Antimatter rectors aren't nearly as far off as sentient AI. Plus, humans fight and die for their country/state/nation because they have something to value and live for besides war. A sentient AI whose only purpose is to act as a combat machine is essentially a slave, and is probably going to turn on its masters at some point... (I recommend watching "Battlestar Galactica" and "Caprica"- not for the fake science or the acting, but because of the moral questions about what is human and how to treat computerized life... The Cylons were originally mass-produced purely as war machines, which is a big part of why they rebelled- as is examined in "Caprica"...) Did you actually *READ* half of my earlier post? I never claimed humans could outperform computer programs- in fact I acknowledges they couldn't. What I said is that humans aren't vulnerable to EMP, computer viruses, or many electronic countermeasures that computers are- which means that a properly-equipped (with EMP, jamming, and/or electronic countermeasures) manned ship could *EASILY* defeat a "superior" unmanned ship with ostensibly superior agility, targeting, firepower, etc... You're sounding more and more like a troll... Did you actually read what I wrote before? It doesn't matter if you have a million targeting computers or just one, an EMP will disable them all just the same. A human, on the other hand, can survive for days with life-support knocked out: as was revealed on the Apollo 13 mission (and a combat spacecraft would likely be much larger- extending the time until oxygen supplies ran low or CO2 levels became toxic without life support...) That should be plenty of time to repair a spacecraft after the battle is over, or pull into a safe spaceport somewhere utilizing the engines under manual control... Losing life support or habitat is really not relevant on the timeline of a space battle. The distances wouldn't be 1+ light second. That's the whole point I made before- did you read it? They'd be a hundred kilometers or so at the most. At that range, you can't dodge a laser... Of course. That's what I said the main niche of fighter-craft would be: patrol and recon duties. They wouldn't be very useful in pitched battles, however. I'm not sure what you're getting at here. I never suggested use of relativistic torchships would be common. The most likely propulsion system is Alcubierre Warp drives. I never said that future computer systems wouldn't be more advanced. I only made the point that we over-estimate drone effectiveness because of our own experiences hearing about Predator drone strikes- which only work half as well as they do because they're against a MUCH less advanced and prepared enemy. A little EMP, and those Predator drones would start falling from the sky... Regards, Northstar

Fewer electronic systems to protect. You don't need a probe core on a manned craft- just the actual controls themselves. This leaves less to EMP-shield, and they can also be built using non-electronic methods such as valves and hydraulic systems (both of which are in fact have seen use in real-life space programs...) You don't have to use fly-by-wire controls for your spacecraft.

It's also been pointed out to me an alternative strategy for making maximal use of Duna's atmosphere when trying to reach a more distant location such as Jool, or Sentar (an even more distant gas giant with rings- a Saturn analog from Krag's Planet Factory) to save fuel. This works best in combination with In-Situ-Resource Utilization, as it costs quite a bit of fuel for the refueling base on Duna... (1) Instead of aerocapturing to a low orbit, or to Ike orbit, aerocapture to a highly elliptical orbit with an apoapsis close to the edge of Duna's SOI. DO NOT unthinkingly make your aerocapture into a prograde orbit relative to Duna's rotation, or you might end up waiting a longer time to make your eventual ejection burn. Make your atmospheric pass on whichever side of Duna is closest to the sun (the orbital direction will thus vary depending on your approach trajectory- this aerocapture will place you into a retrograde orbit if approaching from behind Duna relative to its orbit, but a prograde orbit if approaching from in front...) (2) Raise the periapsis of your orbit above the atmosphere. You won't want an additional atmospheric pass slowing you down. If you have enough fuel, this is also a good time to make a phase shift to your orbit by making a low-intensity burn radially outward from Duna at apoapsis, or radially inward at periapsis. Your phase shift should change the major axis of your obit so it points more in the direction of Duna's movement relative to the sun. (3) To refuel the spacecraft, send a tanker from Duna or Ike orbit. It will cost quite a bit of fuel for the tanker, but will save fuel on the ejection burn of the main vessel vs. aerocapturing to a lower circular orbit around Duna or Ike. (4) Eject the newly refueled interplanetary vessel from Duna's orbit, making the majority of the burn at periapsis with Duna to make maximal use of the Oberth Effect. For bonus fuel savings, and awesomeness, grab a gravity assist from Ike. The major axis of your elliptical orbit will be pointed mostly radially outward away from the sun, and perhaps also a bit retrograde relative to Duna's orbit around Kerbol, so you will need to either perform a phase shift first to shift the direction of your major axis (burn radially outward near apoapsis, or radially inward near periapsis- though be careful, it's easy to accidentally introduce a component in other directions to your burn during the phase shift, creating accidental undesirable orbit changes), or correct for the degree to which your major axis is off by introducing an extra prograde or radial inward/outward component to your ejection burn. The main benefit of this method is, as you can see, is that it saves you a LOT of Delta-V on your ejection burn (up to about 500 m/s worth- if you remember, the base cost of the two part transfer is only 450 m/s more if you make the 2nd burn FROM LOW DUNA ORBIT- so you make up the cost difference this way even before you account for some of the other sources of fuel savings such as shorter and more accurate ejection burns...) HOWEVER, it can take a very long time compared to other methods, is rather complex, and can easily be messed up by unplanned encounters with Ike. Thus, I don't particularly recommend this method, but only thought I'd put it out there for any of you gutsy enough to give it a try- or who had heard of it before, and were curious about some of the details on how to actually do it (which, even now, I've painted in rather broad strokes...) Regards, Northstar

A few minor things I kept busy with in my latest play session... First of all, I brought the Light Munar Fuel Lander back to the Munar Spacedock, and recycled it with the Scrapper Ship there. I got some fuel from doing so, but didn't appear to obtain any RocketParts from the scrapped ship for some reason... Then, I put some of that fuel to immediate use launching an impactor probe at the Munar surface, and transmitted the data for a bit more !Science! Looks like it's going to be fun times seeing what happens when the rest of my Duna armada arrives. Hopefully I don't encounter the bug I did before with not receiving any RocketParts from recycled vessels... (this is a significant problem if it occurs when setting up my Duna colony- my strategy relies heavily on reusing some of the RocketParts from the armada to set up initial mining/refining/base infrastructure. I do have enough RocketParts between the DHEDP and Orion RocketParts Tanker to get by without recycling, however...) Regards, Northstar

If a mod that's supposed to add "realism" makes it so the default state of things is more unrealistic than without the mod (unmodded, at least Kerbals won't die under a few seconds at 15 g's), then the mod doesn't really do what it thinks it's doing- regardless of whether configs allow you to set things straight. Regards, Northstar

Excellent insight- it all comes down to cost in the end. Any space navy is likely to be heavily reliant on railguns for precisely this reason- they pack a large punch for a small cost. 'Fighters', manned or unmanned, are likely only to be useful for scouting/recon missions (a *little* armament on a scout allows it to attack unarmed targets of opportunity). Dodging projectiles fired at you isn't really very feasible in space combat- with no atmosphere to slow the projectiles down, you can easily fire projectiles at any 'fighter' type craft at incredibly high velocities that no fighter could conceivably dodge. Automated targeting systems and high-speed railguns would simply work too well for fighters to ever be cost-effective. The advantage of railguns over missiles or fighters is obvious- you don't have to manufacture an expensive propulsion system for each and every projectile, you simply give the payload all its velocity while it's still on the ship firing/launching it. Propel it fast enough, and dodging it becomes next to impossible. Missiles are slow and easy to intercept (ironically, the best system to destroy a missile is probably a precisely-targeted railgun, not offensive chaff/flak) by comparison... Lasers carry this same concept to an even greater superiority (there's no dodging a well-aimed laser in real life- it will reach any target in such a short time that it can't possibly move before impact...) Given that the main weapons would be railguns or lasers, now what about propulsion? I would assume that for interplantetary warfare to ever occur in the first place, we would probably need a lot more advanced propulsion systems than we have now to colonize other planets in the first place... Forget chemical rockets, forget ion engines- for a warship you're most likely talking antimatter reactors coupled to thermal rockets, or Alcubierre Warp Drives (the only type of warp drive that is probably mathematically/physically feasible). If you can warp right next to your enemy, or approach them at an enormous enough speed with antimatter thermal rocket propulsion to slow you down at your target, then "long range" becomes an antiquated notion. Spacecraft will be capable of traveling from Earth to Mars at significant fractions of the speed of light (or faster than light)- so detecting these craft far enough ahead of time to launch missiles or interceptors becomes next to impossible- another reason combat will take place mainly between large ships with railguns or lasers... Large vessels would have the advantage of having less surface area relative to volume- which makes armoring them much more cost-effective... Especially given the element of surprise, armor becomes invaluable for most ships. You want to ensure your enemy can't destroy you before you even have time to note their presence. Not conventional armor, mind you- a few dozen centimeters of steel does nothing to repel a high-powered railgun. Instead, armor would be largely magnetic (for kinetics) or absorptive (or lasers). Your goal would not to be to present an impenetrable substrate enemy weapons cannot pierce, but rather to reflect and absorb as much enemy firepower as possible... Predictive plating becomes a necessity, due to the projectile energies involved- it's far easier to reflect a kinetic projectile if the armor plate it impacts rotates to create a smaller angle of impact (think of it like skipping stones on a pond)- and the effective armor thickness (should the magnetic systems fail) becomes much thicker. Automated systems to control the predictive plating would of course also be necessary... Which brings me to my final point- automation. It's not quite as valuable as you think... True, an unmanned vessel can be lighter, faster, and more agile than a manned one. And, even on large ships which would probably carry a small repair crew (to repair damage to the vessel between engagements) you would theoretically still want to automate as many systems as possible... However, theory doesn't always match practice. The fact is, unmanned vessels/systems introduce several weaknesses and vulnerabilities that manned ones do not... The first of these, is an extraordinary vulnerability to EMP. All an enemy has to do to fry an entirely unmanned enemy fleet is let off a strong enough Electromagnetic Pulse. If this pulse is strong enough, it can permanently disable enemy electronics. You would expect to see specialized vessels with highly shielded systems themselves built precisely for this purpose- but shielding every single unmanned system and vessel you build to a sufficient level would be extremely expensive, and greatly reduce the mass and cost benefits of unmanned systems versus manned ones. Manned vessels, with their reduced reliance on electronics, and capability to switch many automated functions over to "manual control", would be far cheaper and easier to protect against such an EMP system... The second of these is these weaknesses is a reliance on outside transmissions to control an unmanned vessel. Excepting the development of quasi-magical fully independent advanced AI, which is still a long ways off (and blurs the line on what is human or manned anyways), most unmanned systems would be remote-control. True, you could give an unmanned vessel relatively simple programming to engage enemy vessels, and hope it works. But there are a variety of electronic countermeasures and systems to fool the target-identifications systems of such a vessel that could make this strategy nigh-useless, not the least of which is because such programs would likely have to identify enemies by transmitted signals which could easily be faked or jammed rather than appearance or behavior... If a system is remote-control, then your best weapon against it becomes attempting to imitate the real control system and issue commands telling it to do things like self-destruct or attack allies. Even if this proves impossible, general (and already well-understood) signal-jamming techniques can render a drone a worthless hunk of metal to be blown into pieces at leisure... Should NONE of these approaches work, a remote-control vessel can be most effectively disabled not by targeting its engines, weapons, or reactor- but by targeting its antenna. Destroy this relatively fragile and exposed piece of equipment, and once again, a RC drone just becomes a worthless hunk of metal... And, as a last-resort, you can always destroy the drone-control center (if there are no backup control centers to take over), Phantom Menace-style; though that really only works when it would take minutes or hours for signals to arrive from the next closest control center... As you can see, unmanned systems have a number of vulnerabilities. So in practice, they wouldn't be used that much- or the first interplanetary or interstellar power to use them in symmetrical warfare- rather than asymmetrical warfare against a massively-outmatched opponent (which is the only reason things like drones have worked as well as they have in the modern era- not to be stereotypical, but comparatively primitive Arabs in the desert being attacked by a Predator Drone don't have things like powerful EMP or sophisticated electronic countermeasures to co-opt its command and control systems...) would be in for a massive surprise, when their "superior" drone force would quickly be defeated by a manned force using things like EMP and electronic countermeasures to their best advantage... I hope we never see warfare in space. It's my dream that we can reach some sort of world government BEFORE we go off setting up too large a presence among the stars. But, if this should happen, these are some trends to be aware of... Regards, Northstar

Indeed. Deadly Re-Entry definitely makes Kerbals far too fragile (more so than their real-life counterparts). That's one reason I don't use it. All you need to do is place your astro(Kerbo)nauts in an "eyeballs in" position, and they can realistically sustain short (10 second) peaks of 20 G's. Pulling that many G's with DRE would kill your Kerbals. It's simply not a realistic mod- it's another one of those mods that overdoes "realism", and actually makes the game less forgiving than real-life. Every game has them- mods by cynics who don't actually understand real-life: and DRE is just KSP's version. Regards, Northstar

The saga continues... So, as planned, the Duna Science Module lowered it periapsis to 12 km. However several F5/F9 *cough* "simulations" revealed that was far too low, so when the Duna Science Module was close to Duna, I raised the periapsis to 16 km: Then, on the way out of the aerobrake, I decided to circularize the orbit then and there: Why, you might ask? I had an idea. A brilliant idea. A most conspicuous idea! I was to land the Duna Science Module on the surface of Duna here and now! And, after many, many, many attempts to perform the entire landing with MechJeb, I realized an automated landing was all but impossible (MechJeb did everything from literally landing ON TOP OF the decommissioned probe used to mark the landing site to starting the deceleration burn late and smashing into the ground at 256 m/s to landing a couple dozen meters away at 36 m/s...), and ended up performing a hybrid landing where I took over the final part myself. I did manage to capture some nice screenshots before I took over though: This constituted my first manned interplanetary landing! Though I had already sent an interplanetary mission to Jool before in a previous save right before an update forced me to abandon the mission (the poor Kerbals got to the system, but never got to use the landers...) Further, this should also allow the 2.5 meter inline radiators of the Duna Science Module to effectively dissipate the heat from its reactors- heat convection is much more effective than heat radiation, but requires atmosphere. Although the original plan had been for the radiators to dissipate the heat in space, an early bug or a later nerf to the inline radiators allowed them to dissipate the heat at first, but then suddenly proved inadequate for prolonged use in space after the Duna Science Module was already en-route to Duna... So, we'll just say that this was the plan all along... In accordance with my newly-found ability to run the Duna Science Module's reactors and electrical generators as long as I want, I now claim POWER, UNLIMITED POWER! In all seriousness though, this does finally allow me to run the Science Lab, on Duna, AS LONG AS I WANT! Or... until the nuclear fuel runs out. Though, with nuclear fuel reprocessing at the same said Science Lab, that's going to be a LONNNGGGGG time from now... (by which time I should at the very least have a Uranium or Thorium-mining infrastructure up on Duna...) The Duna Science Module doesn't have enough fuel to make it back to orbit again now, unfortunately... But that's not really a problem, seeing as it's already in the location where I plan to build my first Duna base... (when I'm done with it, I'll just recycle it with an appropriately-equipped rover) The Kerbals can get back to orbit on one of my two Duna spaceplanes when they arrive, if so desired (though neither has room for more than one passenger, so it would take at least two trips...) Or, on a rocket built on Dunn- as the spaceplanes have had some issues with buggy collision boxes when loading/unloading passengers (don't forget the poor Kerbal strapped to the front of that fuel tanker, riding to Duna that way as a result of just such a bug...) So long Kerbals! Talk to you again in a week or two when you have some results to transmit! Regards, Northstar

OK, so more news on my Duna operations! First of all, the Duna Science Module got an Ike encounter near apoapsis that decreased the eccentricity a bit and pulled the periapsis back above the atmosphere: I actually kind of figured this would happen at some points- I just kind of hoped it wouldn't be quite so soon... Regardless, I was getting impatient with how long the aerobraking was taking... Here's the Duna Crew Module after yet ANOTHER aerobrake pass: So I decided to just screw efficiency and waste a bit of fuel lowering the periapsis further so I could get this over with already: It looks like I lowered the periapse a bit too far though. Below the DCM is having to *RAISE* its apoapsis on the way back out of the Dunan atmosphere after it became apparent that at the rate its orbital velocity was decaying, it wasn't even going to make it back out... (Duna's atmosphere is far too soupy compared to real life Mars- Duna's atmosphere is 20% as think as Kerbin's at sea level. Mars' is only 1% as thick as Earth's at sea level, by comparison. Duna does have a reduced scale height compared to Kerbin though- whereas in real life, Mars' atmosphere falls off more gradually than Earth's...) I also plotted a maneuver node to bring the Duna Science Module's periapsis back within the atmosphere, this time much lower than before: I decided to circularize the Duna Crew Module's orbit at about 100 km (though I changed the maneuver node to circularize at 104 after thinking a bit: so that I could maintain a constant 100 km+ time-warp factor with the vessel loaded) After seeing how the Duna Crew Module played out with a 14 km periapsis, I might want to re-consider utilizing a 12 km periapsis for the Duna Science Module. Then again, its apoapsis *IS* much higher, so it has a lot more velocity to bleed off, and I don't necessarily mind spending a bit of extra fuel (I'll think of it as compensating for KSP parts, the lack of budget restrictions, and Kerbal's current lack of need for life support being a bit OP'd at times), but I *DO* mind spending a bit more time on this aerobrake... I do *NOT* want to have to go in for another pass after this one... Regards, Northstar

Great job! And the KW 3.75m Docking Port is fine. Note that I said: "the docking port must be a Clamp-O-Tron Senior or larger". So a 3.75 meter port is definitely OK. Congratulations on setting the high score for the Challenge! And, a 1.2 kiloton rocket is what I consider a huge rocket. I don't know about you, but I rarely launch anything bigger than that- in fact I've only launched 3-4 rockets larger than that (all silly-enormous SSTO's) to date... 25% is a great payload fraction too- if you could design a rocket like that in real life, I'm sure NASA (or any contractor) would be happy to have you. Regards, Northstar

It's about the Delta-V of the transfer, not the distance to the destination, that determines the usefulness of the Oberth Effect. I feel the need to point out this distinction because, again, you don't *have to* use the lowest-energy transfer possible to get to Eve or Duna. If you're running a manned mission with a life-support mod, or playing for realism, it's very likely you'd want to eject with excess speed to get to your destination faster. In that case, a fast transfer to Eve or Duna can require just as much Delta-V (and benefit just as much from the Oberth Effect) as a slow transfer to Jool or Moho... In real life, NASA wants to wait on a Mars mission until it can develop propulsive systems that can get a manned mission to Mars in much less time than current chemical rockets allow. It's not desirable to make a minimum-energy transfer, and have a crew stuck in interstellar space (with the heavy radiation exposure that entails) for months at a time. That's a big part of why they're eying the VASIMR propulsive system so eagerly... (it could allow much faster transfers, thanks to its higher ISP, when scaled up to a multi-megawatt scale with sufficiently advanced nuclear reactors) Regards, Northstar

Great job! Cool-looking and elegant design too! Too bad there wasn't a bonus-point category for just looking totally badass... I'll add you to the Scoreboard. By the way, I've decided to add another week to the Challenge, so keep swinging by if you want to see the newer entries (or even try and snatch up that first-place spot for yourself). Regards, Northstar

The heavy lift rocket is supposed to be highly flexible. If it can lift a payload with a docking port, then it can life a payload without one. But not necessarily vice-versa. The payload doesn't actually have to do anything, so it should be easier than a real mission... Not at all. KSP-Interstellar fusion and antimatter reactors can easily be filled with TAC Fuel Balancer (which is on the list of allowed mods) while on the launchpad... And fusion reactors come with an initial load of Deuterium/Tritium, Helium 3, etc. for free. It's only if you need to provide them with additional nuclear fuel on another planet that you might find yourself gathering these resources in-situ... (and the only places you can gather Deuterium and Lithium for Tritium-breeding are those with oceans- Laythe, Kerbin, and Eve) The antimatter reactors may require some infrastructure (which is silly anyways- realistically you can produce the electricity needed to run a vacuum-laser for antimatter collection much more cost-effectively in ground-based research/industrial facilities than in small rocket-deployed labs built by a space program...), but you can also easily circumnavigate this with TAC Fuel Balancer. And besides, there are no rules against filling rockets/spaceplanes with resources on the launchpad or runway (or any alternative launch facility you built on Kerbin for that matter)- if you wanted to fly a spaceplane with Kethane jets for the atmospheric stage (as stupid as that sounds- they get terrible fuel-efficiency), and fill it on the runway, you could do that... Aerodynamic parts, when properly used, help you get the rocket/payload to orbit. You can use them on the rocket, but it would be unfair and make no sense to allow them on the payload- otherwise people could just launch a payload composed entirely of giant wings... Air intakes are banned on payload for the same reason- they help you get an air-breathing rocket into orbit. The weight limit it about [1] making sure people don't win the challenge (if you play for points) just by building behemoth rockets that weaker CPU's couldn't possibly handle (the part-count penalties are in place for the same reason, as well as to encourage simplicity and elegance of design), and [2] Encouraging players to maximize the efficiency of their rockets, rather than just adding "Moar Boosters!" What you said about "who can put the most of that 1.2 kilotons into payload" is precisely what it's being sought after. It's called "payload fraction", and is one of the most important factors sought after in real-life (as well as many KSP player-made) rocket designs... I've actually never heard of that mod before. It sounds interesting, and I might have considered allowing it on the mods list if I had seen it suggested earlier. However, as I understand it, that mod places no limits on the mass:volume ratio of the test payload- so you could easily make a tiny payload many times denser than lead, or an enormous payload less dense than a balloon. I'm not sure I like the implications of that, and it would certainly give players submitting entries after it were allowed an unfair advantage... It *IS* just about building a huge, powerful, and efficient lifter. There are size and part-count limits on the rocket as a whole, but when you get down to it, that doesn't change the basic nature of the challenge. And you keep mentioning "payload rules" as if there were several- but really there are only two: [1] Don't use parts in the payload that exploit aerodynamics to help get the rocket to orbit (like wings or air intakes) or otherwise help get the rocket to orbit (such as engines used during the flight) [2] Include at least one docking port of appropriate size on the bottom of the payload. Those rules aren't very complex, and other than some obvious clarifications to prevent players from doing things like transferring all their leftover fuel into an empty tank and then calling it payload (the point of this challenge, obviously, is that the lifter could be used for things other than just giant fuel tanks), there aren't really any other restrictions that apply to the payload... So, why don't you *stop* being a PITA about things, and go build a rocket already? I've decided to extend the challenge by an additional week like I mentioned before. This decision was actually prompted mainly by my attempts to build my own entry, which were met with KSP totally bugging out and causing my rockets to halfway disappear on the launchpad- but I'd also be more than happy to see what you have to submit to the challenge yourself. Regards, Northstar

OK, well I didn't make it in under 20 minutes (even though my vessel was easily capable in making it in under 15 min with better piloting), but I did beat all the prior speed records. I present, the glory of a 20 Mn Nuclear Pulse Rocket (from Nyrath's Orion mod, which somebody mentioned earlier already) Touchdown a bit before 23:00, even though I didn't manage to grab a screenshot until 23:04. Put me down for 23:00 (might have quicksaved during descent- so can repeat it if you guys need the proof) EDIT: Loaded the quicksave, and managed to grab a couple screenshots before 23:02, even though I took it a bit slower landing this time. Also, managed to land on a rooftop for the win! Put me down for 23:00 Regards, Northstar

No rules? Prepare to see it done in under 20 minutes! (entry to come soon) - Northstar

Ahhh... OK. I hope you enjoyed the challenge! I was hoping to see a few more entries than this, but oh well... I might spice things up with an entry of my own, and give it another week. Regards, Northstar

I encourage you to submit an entry! The payload rules aren't complex actually. Basically, just use an appropriate-sized docking port for the size of the payload (now that I see how heavy some of the payload here are, maybe I should have given rules for 3.75 and 5-meter payloads as well- I guess I'll just tell you guys to practice common sense and build something that won't wobble like a wet noodle when docked at this point...), keep the payload separate from the stages used to ascend and circularize the orbit, and don't use things that are only of utility in-atmosphere as part of the payload (such as air intakes or wings). Other than that you've got pretty free-reign as to what is in your payload: you can even include solar panels or nuclear reactors (conventional fission only, please) in the payload if you want, and use the electricity to help drive KSP-Interstellar plasma engines in an upper stage to circularize the orbit, and maximize payload fraction... I would only ask that you throw a Microwave Beamed Power Transmitter onto the payload if you do this, so hauling the electrical equipment to orbit would at least have some conceivable justification... Regards, Northstar

Ahhh, I see- not sure how I missed those details before... I thought those were the engines, not docking ports, in the last screenshot- since it looks so similar to the 2nd-last screenshot. But now that you point out there are no engines on the staging tab... Where did the engines go from the 2nd-last screenshot though? (I don't see them floating nearby as debris- and without thrust or having used RCS, the rocket couldn't have moved far away from them...) Sorry about all that. I've been sick with first a cold and then a upper respiratory infection and cough most of this week (which has made it hard to sleep- thus making me tired and sleep-deprived), so I haven't been quite as keen on the details as usual... You're good, no changes needed. I'll enter you on the Scoreboard shortly... Regards, Northstar