Northstar1989

There's another possibility, that would be rather cool- have a secondary star orbiting KERBOL at a large distance. I'm thinking a Red Dwarf, something like Nemesis - a hypothetical extremely dim Red/Brown Dwarf once thought to be orbiting Earth at approx 1.5 light-years (the idea was proposed in 1984, though later disproved). Smaller stars *ARE* capable of orbiting larger stars like this, even if it turned out not to be the case with Sol (the sun Earth orbits). 1.5 light-years isn't the minimum distance for a star, either. In fact, another Main Sequence star (one much like our own) Gliese 710 will pass just under a light-year away from Sol in 1,477,000 years. The effect of this- a mere 5% increase in the rate of comets entering the Inner Solar System from the Oort Cloud: http://en.wikipedia.org/wiki/List_of_nearest_stars#Future_and_past http://en.wikipedia.org/wiki/Gliese_710 So, you could easily have a Red or Brown Dwarf orbiting Kerbin at 1/11th (1 light-year scaled down to KSP-scale) of a light-year. Still a long way to travel, but with a ship traveling at 20 km/s (difficult but attainable in KSP- especially if they add VASIMR engines as late-game tech) that's "only" 497,712 days (1363.6 years) - 7.16 minutes at a 100,000,000 x time-warp. Interestingly enough, it makes me wonder if in 1.477 million years, when Gliese 710 is only a light-year away, we might not consider sending a manned mission to it in real life (if humans haven't nuked themselves by then...) If we've developed 0.1 C Alcubierre Drives by then (assuming we find a way to build them or something similar in 1.4 million years), we could reach it in "just" 10 years... (or as little as 1.2 months with a 10 C drive- which we might never find a way to pull off) Regards, Northstar P.S. 0.1 C is achievable even without an Acubierre Drive- though use of an Antimatter Rocket, for instance...

Re-entry of a Space-X style reusable launch stage (in order to make it work with the in-game disappearance of craft at 23 km, the launch stage has to launch "straight up" well above the atmosphere to give the reusable upper stage time to circularize before switching back to the launch stage) And, YES, despite the tiny parachutes (mostly to keep the engines pointed down and kill horizontal speed- they don't reduce the launch stage to a safe landing speed) the launch stage does make a soft powered-landing, like Space-X is currently attempting. I also deployed the parachutes a little early here- I didn't mean to deploy them while the rocket was still on fire. Re-entry of the reusable upper stage (zoomed MUCH closer in- it's 2/3 the diameter of the launch stage) The re-entry speed is super-high because I had JUST enough time to switch to the upper stage after landing the launch stage before the upper stage hit 23 km (the payload was a bit heavier than the nominal lifting capacity to an orbit at that altitude, but had its own engines, so the reusable rocket system didn't finish the circularization)

I present the final component of my Sentar Mission: A seaplane- yes, a friggin' seaplane! This is the mobility system for my exploration of Erin (the Laythe-like moon of Sentar). It's electrically powered, and designed to operate off the beamed power from the Mission Vehicle (although it has a great deal of battery capacity, and a few OX-STAT panels as a backup power system, VERY LITTLE light should penetrate through Erin's thick atmosphere at that great a distance from the Sun. Hmmm, maybe I should have attached some lights to it so the Kerbonauts can see where they're going- nahhh, they've got lights on their spacesuits! I wonder what the battery life on those lights are though...) The recovery of the Reusable Launch Stage (shown below) and reusable drop-tanks (shown above) went without a hitch: And recover of the Upper Stage was also successful (although MechJeb decided to blow all the fuel I was saving for a soft landing as soon as I activated Landing Guidance, it still had enough parachute mass to touchdown without breaking anything...) Now that all mission components have been launched to Kerbin orbit, it's time to assemble the Lander and Mission Vehicle with their respective transfer stages (due to its low mass, the Erin Seaplane launched already assembled with its own transfer stage), and get all the components to Sentar! The remainder of the Duna armada, meanwhile, also nears its destination. Among the components still en-route are the Duna Supplementary Equipment Vehicle (complete with a FUNCTIONAL DUNA ELECTRIC HELICOPTER!) and the Duna Heavy Equipment Platform (hopefully its Orbital Construction functionality still works- I'm almost afraid to test it after all the difficulties I've had with the Munar Spacedock... If it doesn't work, I guess I can poke around on the surface with multiple round-trips to the surface using my two spaceplanes in the armada, and waiting for the next transfer window home... Or maybe I'll just send contingency equipment on an Orion Nuclear Pulse Rocket- which has so much Delta-V it basically can ignore transfer windows...) Regards, Northstar

It's a slim hope that he'll see the post even if it's re-posted so he can see it, as he's not as active as he used to be. But it's worth suggesting legitimate ideas for the mod to FractalUK as long as they're made respectfully. My requests, ideas, comments, have been the very epitome of polite and curious. Although it's hard to get tone across in an electronic communication, why do you think I end every post with "Regards" in the signature? To show my respect for the reader. As for when FractalUK decided to ignore me, that was one particular moment when I got carried away with an idea/discussion because of my passion for it. Ignoring somebody is always a shame though- because you can't see anything more they do, including if they stop doing whatever was annoying you and go back to being calm, polite, agreeable, etc. A *good* idea gives potential directions for the growth and expansion of the mod. One person can't think of and research everything- which is why I choose to point out a technology he (and most people) have probably missed that would be a good fit for the mod. If he dislikes it, it's very easy for him to ignore it- he can't even see my posts, so all he has to do is ignore the idea. But if he *likes* the idea, maybe it'll even make its way into a future Release, and maybe he'll even consider un-blocking me so he can ask me more questions or to obtain more research on the idea for him (which I would be happy to do). Regards, Northstar

I'm not bugging him- it's a legitimate and well thought-out idea, with a link to back it up. FractalUK has shown in the past that he is open to listening to good, serious ideas. He even listened to and gave his thoughts on my own ideas back before I got a little too insistent with him on one particular idea (can't remember which, and have had a hard time locating the conversation it was so long ago). So, rather than attack me, why don't you actually look at my idea, seriously think about it, and consider re-posting it so it can be considered by FractalUK if you like it. Regards, Northstar

@Everyone I'm pretty sure FractalUK added me to his "Ignore" list a long time ago when I was bugging him on this thread a bit, so if you like the idea below, SOMEONE PLEASE RE-POST IT so he can see it. Simply copy-and-paste everything that follows: @FractalUK In my continuing quest to research up new and improved technologies that would be appropriate to KSP Interstellar, I came across the following propulsion system that would make a suitable upgrade to Thermal Receivers. The technology could/should act as an alternative (upgraded) configuration for the Thermal Receiver, in the same way as Direct Conversion Generators are alternative configurations for generators: CW Plasma Receiver (Based on the CW Plasma Thruster described at http://en.wikipedia.org/wiki/Laser_propulsion#CW_plasma_propulsion) Basically, this in an alternative way to turn beamed power into ThermalPower for Thermal Rockets and Thermal Turbojets (the described technology is for a thermal rocket using internal propellant- but with a little engineering you could definitely use air as the working mass instead). Rather than simply heating up a Heat Exchanger to heat the propellant, the propellant is exposed to a very intense laser beam to heat it up into a plasma as it passes through the device. This allows MUCH higher temperatures to be reached than with a Heat Exchanger (the technology in current Thermal Receivers), and thus much higher ISP ratings can be achieved (approximately 50% higher- an ISP of 1000s for hydrogen). This could act as a higher-ISP variant of the normal Thermal Receiver, possibly requiring electricity (or perhaps the rectennas to turn Microwave Beamed Power into electricity could be built right into the upgraded Thermal Receiver), but producing relatively less thrust for the power (per E = 1/2 * m * v^2) as well as engendering a certain level of inefficiency and WasteHeat production- much like a Plasma Thruster. It has some similarities to a plasma thruster, in that electricity is required to run the laser- but its internal workings, conceptual basis, and TWR/ISP are *MUCH* more similar to a Thermal Rocket. And, like any other thermal rocket, it can be used on virtually any propellant- including atmosphere in a Thermal Turbojet- not just those propellants which are easily ionized, like in a Plasma Thruster. I would suggest for simplicity' sake it just be an alternative form of the Thermal Receiver, that should become available at the same time as Gas/Plasma Core Fission Reactors (the technologies and conceptual basis are HIGHLY similar), and simply produces ThermalPower from Microwave Beamed Power at a much higher "Core Temperature" (for Thermal Rocketry ISP calculations- normalized to an ISP 50% greater than with traditional Thermal Receivers) than a normal Thermal Receiver, but much less efficiently than a standard Thermal Receiver (the laser could be assumed to produce WasteHeat, at a constant % of total power usage), and with possible issues of needing to dissipate WasteHeat production (though, then again, maybe not to a great extent- the heat from the laser could possibly be shunted to pre-heat the gas before it passes through the laser focus...) The main reason for this suggestion is that it would fill a gap- Beamed Power Thermal Rocketry becomes increasingly inefficient as you develop better and better reactors that leave its (relatively low) ISP values in the dust, despite just being another type of thermal rocketry that is theoretically capable of just as high ISP values with appropriate technologies (like this one), and an increasing availability of greater and greater levels of Beamed Power as players develop infrastructure based on the improved reactors. I suspect it would also be relatively easy to adapt existing code modules from the Thermal Receiver and Plasma Thruster to provide all the needed functions for this new (upgraded) variant of the Thermal Receiver. Regards, Northstar

I made some corrections to the numbers in this thread, and updated the explanations a bit. I hope it's still useful to you guys! Regards, Northstar

Lots more going on- my Sentar System Mission (SSM, in future abbreviations) is finally shaping up and most of the components have now been launched to Kerbin orbit... First of all, there is the Sentar Transfer Vehicle (STV) Mk1- which is to be used to transport the Sentar Mission Vehicle (SMV) to its destination, as well as to return the Return Module (the SMV splits in half- leaving the reactor, microwave transceivers -the transfer vehicle has its own receivers- and some empty fuel tanks behind while the rest of the vehicle heads back for Kerbin) when the mission is complete. Here it is blasting off from Kerbin: The STV was so over-engineered it acted as an SSTO (minus the disposable Solid Rocket Boosters), however- so I had to dump the launch stage in a "graveyard" orbit at around 900 km, since the full vehicle is too long and high part-count to safely transfer the SMV without ripping apart... The SMV will be rendezvousing with the transfer vehicle in an even higher orbit (to keep the launch stage out of loading-range) in order to initiate hard-dock and make the transfer to Sentar. Second, I launched the Sentar System Lander module- which includes a reusable lander (designed for use on Erin, Skelton, and Pock- it doesn't have enough Delta-V to ascend back to orbit from the surface of Ringle or Thud without a separate fuel-lander), a service module to transport the lander around and refuel it between landings, and a disposable fuel-tank which also improves the aerodynamic profile of the rocket for aesthetic/roleplaying reasons (as I am not running FAR yet). All launched atop a single Heavy Reusable Thermal Launch Platform- which now has a much greater lifting capacity thanks to my 2nd Reactor Cart: The recovery of the launch and upper stages of the Heavy Reusable Launch Platform: Note that the launch stage did a weird bouncing-act where it kept bouncing sideways along the (relatively level) ground and GAINING speed while it did so, despite my attempted use of engines to put it to a stop. I'm going to ignore this (totally unrealistic and physically-impossible IRL) bug, and treat it as a fully-successful touchdown for roleplaying reasons... The upper stage touched down HARD though- at something like 17 m/s (sorry, no screenshots of most of the landing), due to making an unpowered descent. I'm surprised the landing legs sufficiently cushioned the impact (they've failed to in similar landings before), and no parts broke. I guess that just shows how robust and over-engineered my designs are though! The SSM Lander Module (shown below) and STV Mk1 (not shown) then deployed their Microwave Transceivers in Relay Mode so as to provide additional relay-points for the launch of the remaining modules of my Sentar Armada, ensuring sustained access to beamed power, and the shortest-possible relay path lengths (to minimize distance-losses) Third, I launched the Sentar Transfer Vehicle Mk2- an entirely redesigned version of the basic STV Mk1 that relies MUCH more heavily on ion thrusters for the later part of its transfer (an engine cluster of: two KSP Interstellar plasma thrusters, four NearFuture dual-stage four-grid ion thrusters, and a single 1.25 meter thermal receiver form its final stage propulsion system). It may, depending on remaining fuel budgets and Delta-V predictions for the return, form the transfer stage for the Return Vehicle instead of the STV Mk1's final stage. A lot depends on how the capture and lander-missions go. That's not all though! I also made the ejection burn for the second Sentar/Inaccessible Probe. As this was performed at the closest-approach of a Kerbin-dive following a Munar gravity-assist, the final trajectory was radically different from the first probe- likely setting it up for different flyby maneuvers when it dives back inwards on the Kerbol system. It also likely consumed less fuel than the first probe in setting up its trajectory- due to the Munar gravity-assist, the benefits of the Oberth Effect, and the fact that it made only the minimal burn necessary to escape Kerbin's gravity well... (the first probe made a much faster and higher-energy escape burn with reduced eccentricity) And, finally, the upper stage of the Medium Reusable Launch Platform that I had in orbit made a recovery to the KSC launchpad (quite literally- it landed back on the launchpad), to be re-used in the future for one of the final components of my Sentar armada (a mobility system for Erin- but its precise nature is a surprise for now...) Regards, Northstar

That's HUGE- how did you get it away from the Runway/Launchpad without it breaking apart on the slightest bump? I used the LARGE rover wheels for my rover, with "only" 5 reactors and 3 generators (your design is highly inefficient for Solid Bed Reactors, by the way- two reactors can "share" a single generator), and I had trouble with even TINY bumps in the terrain causing it to explode! I think I mentioned the cost as well, yak know? But I wouldn't consider a Construction Time plugin fun or realistic by any means- a "real" space program would have its mission planned out years in advance- but that's simply too much to ask of a single KSP player... The cost should (in theory) be worth it however- unlike sticking those reactors on a rocket, you get to reuse them ad-infinitum if you keep them on the ground (with only a possible small cost for new reactor fuel- which you could easily produce from centrifuging the oceans of Kerbin for Uranium and water, and producing the Ammonia needed to make Uaranium Nitride from the atmosphere- or, just using TAC Fuel Balancer). And, if the devs include a recovery mechanic to the Budgets system, then the ability to build high-performance reusable rockets will be well worth it. Regards, Northstar

It's Wikipedia. What do you expect? Half the time articles end up with [Citation Needed] tags because a link breaks (a non-stable URL is used), and then gets deleted as a result- and then later editors come around and label it as lacking citations... This isn't a problem unique to Wikipedia by any means, actually- it was less than a year ago that as many as half the URL's referenced in US Supreme Court decisions were broken as well: http://www.nytimes.com/2013/09/24/us/politics/in-supreme-court-opinions-clicks-that-lead-nowhere.html?_r=0 That's with LASER-based beamed power that you have that possibility (and, despite using the name "Microwave Power Plant", that's what the only thing the disaster in SimCity could have plausibly represented...) The power plant and disaster was in SimCity 3000, not SimCity 4 (which cut out all futuristic power technologies, and had a highly inaccurate cost-model where Wind and Solar cost MORE in running-costs than Coal, and were cheap to build), by the way. If a long-beam MICROWAVE transmission misses its target, it's almost completely harmless- long beam microwaves like those proposed for use in power transmission systems don't interact strongly with everyday matter- only metals to a weak extent, kind of like X-rays. It takes large, specially-designed rectenna device to intercept them- if they missed their target, and hit somewhere else in a city, they might fry a few radios and other devices with antennas, but they certainly wouldn't cause fires or explode sections of a city like in the game... Of course, the rectennas to intercept long-beam microwaves, such as those that would be used for powering cities, are roughly a kilometer in diameter. While they can be built in folding layers into a hull, kind of like internal antennas, they are still are going to have much lower efficiencies with spacecraft use than the ones seen in KSP-Interstellar (think 5-10% efficiency with dishes at least four times the size of the ones currently used). Long-beam arrays also experience greater power-loss over transmission distance (but almost negligible atmospheric interference). More likely, the Microwave Power system in KSP-Interstellar represents short-beam arrays, such as you can generate with magnetrons (the devices in your microwave ovens) instead of gyrotrons (much more expensive devices currently used in high-tech applications and heavy industries such as metallurgy). While THIS wavelength is short enough, and experiences enough interaction with everyday matter, that a mis-targeted beam could cause fires in a city in the dozen-Gigawatt power range or above (though devastation on the level of the SimCity disaster would take a beam in at least the hundreds of Gigawatts- MUCH more powerful than what that power plant provides in-game), it can be reasonably used with transmitter and receiver dishes on the kind of scale seen in KSP-Interstellar... The problem with short-wavelength microwave beams like that is that they also have relatively strong interaction with the atmosphere- which is why you experience such strong power-loss when transmitting through Kerbin's (or worse, Eve or Jool's) atmosphere. Not nearly as bad as a laser-based system on a cloudy day (which can reach over 99% power-loss), but still nothing to sneeze at- especially if clouds get in the way... That's entirely a matter of opinion. I think a 15% improvement is worth the cost and effort- SRB's are still MUCH cheaper than liquid-fuel rockets per ton of propellant, and I would be perfectly willing to use air-augmented SRB's for the ISP levels (500+) that actually exceed that (400+) of LHX/LOX rocketry (even if the extra ducting weight means that the performance is still inferior to LH2/LOX). It would be especially useful once budgets come out- as a middle ground in terms of cost-effectiveness between traditional SRB's and liquid-fuel rockets (if they get the cost-relation between LFO and SRB's right with Budgets, which is unlikely- more likely the cost difference between the two will be MUCH less than in real-life in the game...) Air-augmented liquid-fuel rockets also outperform their traditional liquid-fuel counterparts in ISP by a large margin, and, despite their extra weight, have a significant niche in potential spaceplane design (which is where they have received the most focus IRL). While heavier than rockets (which are MUCH lighter IRL compared to jet engines IRL than in KSP), they are still lighter than jet engines, and have an ISP intermediate between the two. Their main utility is, as stated, spaceplanes- where extra mass is less of a penalty because wings/lift are used to counteract gravity instead of thrust, the engines can be reused after recovery of the spaceplane (lowering the impact of initial engine cost), and the plane spends a much longer period of time in the atmosphere than a rocket- to build up speed. And, like I said, their TWR is still better than a jet engine (which is abysmal IRL, but great in KSP). Come to think of it, maybe LFO air-augmented rockets DON'T have much of a use in KSP, because the niche they would fill is already occupied by jet engines (which are FAR TOO POWERFUL, and have an effective ISP roughly 15-16 times their listed ISP, due to the game incorrectly accounting IntakeAir in the fuel-consumption calculations...) I still stand by the potential utility of air-augmented SRB's (intermediate performance between "normal" SRB's and the LFO engines) once budgets comes out, however. Regards, Northstar

I hare to burst your bubble man, but 64-bit is probably never going to happen with KSP. Unity is simply too slow to adapt, too archaic, to ever fix the problems with their program that make it unreliable for 64-bit for a program like KSP... If you look at the poll at the top of that thread, 1 in 4 people who attempted to install that 64-bit hack of KSP ended up with the game crashing/breaking. Something like that would be completely unacceptable for the official version of the game sanctioned by Squad, and unfortunately is nothing Squad can fix, as it's mainly a problem with Unity itself... So unless Unity gets its act together at some point, and starts upgrading their program to work better with things like 64-bit and OpenGL (which is unlikely), don't expect any major improvements to the basic architecture of KSP anytime soon... That being said, there ARE a lot of optimizations they could make with a dedicated and experienced performance-optimizer on the dev team (the kinds of things in Active Texture Management are just one example)- but Squad seems to have their heart set on keeping the dev team small and in-house, and probably isn't going to ever bring anyone on like that despite the potential benefits... Regards, Northstar

ARE YOU KIDDING ME? Are you seriously trying to pull my chain? There's nothing any more theoretical about Solar Thermal Rocketry than there is about Microwave Beamed Power or Molten Salt Reactors (the still under-development in real-life reactors you use for your BASIC fission reactors in KSP Interstellar!) In fact, it's basically the same concept as a concentrating solar power plant- only the thermal energy is used to power a thermal rocket (already in KSP Interstellar, and already a real life technology that was demonstrated with nuclear thermal rockets) instead of to generate electricity. There's nothing in the linked articles that even mentions airships, so what are you talking about? Plus, even if it were a propulsive system that was looked at for airships, there's nothing about the propulsive technique that in any way limits or restricts it to airships. That's about the equivalent of saying that because propellers were looked at for use on airships, they must be a technology specific to them... You *do* realize that jet engines require a bunch of ducting as well, and we still use them. And, as the article states: "leading to greater effective thrust for any given amount of fuel than either the rocket or a ramjet alone" Air-augmented rockets are strictly superior in terms of TWR to Liquid Air Cycle Engines, as they require less additional mass, and yet those were used at one time as well, before the shift to rockets over early attempts at spaceplanes... As the Wikipedia article points out, a large portion of modern missiles (weaponry) are in face air-augmented rockets. So I don't have to justify or defend the technology- the proof is in the pudding, so to speak. The ducting might be heavy, but the ISP is *doubled* for an SRB. If you do your research, you will see the widely-cited figure of a roughly 15% performance increase from air-augmentation of SRB's. This is certainly less than a 100% increase, but it does mean that the technology works. Regards, Northstar

Ahhh yes, but some of the most valuable real-estate in the solar-system is closest to the Sun. Not only is there an abundance of solar energy (just IMAGINE the potential from huge farms of reflecting mirrors in near-Kerbol orbit shining onto a single craft's thermal receiver with a plugin basis similar to Microwave Beamed Power- the ThermalPower would be ENORMOUS- and could also be turned into electricity at a surface area efficiency roughly comparable to using PV panels in the first place using a generator on that craft, if need be- but without having to send nearly as much mass to low Kerbol orbit as with PV-based solar farms) but there is also an abundance of ISRU resources on Eve, including antimatter in its orbit; and it actually takes LESS Delta-V to get from Eve to Jool or further out in the solar system, due to the Oberth Effect, than it does from Kerbin... I'm well aware of that (I've probably been using KSP Interstellar long than you have), but solar sails have VERY low thrust, because they don't have any working mass other than the "mass" of a photon. Thermal Rockets powered by collecting mirrors have a huge thrust advantage because they have actual mass to propel with than energy... Regards, Northstar

@NeoArcario Actually, the Thermal Tubojet has a lower ISP and a higher thrust for the amount of ThermalPower used. But that doesn't matter, because the propellant mass is freely-available atmosphere instead of internal fuel... The Thermal Turbojet doesn't work once the air becomes thin in the upper atmosphere, though. I *have* been bugging FractalUK to include Air-Augmented rockets, which would basically be a middle ground between a Thermal Turbojet and a Thermal Rocket when applied to the thermal rocketry line (the technology also works for chemical rockets though)- using both air and internal fuel simultaneously rather than exclusively. Come to think of it, that would make a lot of sense as an additional propellant-mode on the Thermal Turbojet... http://en.wikipedia.org/wiki/Air-augmented_rocket Post something about it yourself if you want to see it, though- I'm pretty sure he somehow has blocked all my posts so he can't see them. Regards, Northstar

@FractalUK I've become convinced you can't (or won't) read anything I post here because you've blocked or ignored my posts or something, but in case you can, here's another idea for propulsion systems in KSP Interstellar I stumbled across, and this one wouldn't be very difficult to implement at all: Solar Thermal Rockets (the link: http://en.wikipedia.org/wiki/Solar_thermal_rocket#Propellants) This would be a more powerful than collecting solar energy with photovoltaics, beaming the power to another craft with a Thermal Receiver via Microwave Beamed Power, and then using that power for a Thermal Rocket- as instead of a Photovoltaic panel, what this would basically use is mirrors to concentrate sunlight directly onto a Thermal Receiver. Using mirrors eliminates the inefficiency factor of PV cells (mirrors can reflect close to 100% of the incoming visible light to be turned directly into heat at the thermal receiver, instead of peak 30-40% efficiencies with space-quality PV composite-cells), and thus attain around 3-4x the power production for a given collector surface area. Deployable mirrors are also much lighter than composite PV cells per square meter... Thermal Receivers already work fine for the technology- and have a NoSurfaceAttach rule already implemented, so line-of-sight to them would normally be expected- though you could implement a line of code requiring line-of-sight between the mirrors and Thermal Receivers if you wanted. All that would be needed is a concentrating mirror part- it would look a bit like a solar panel, except it would be thinner (more like a solar sail), reflective, much larger (to reflect useful amounts of sunlight), lighter, and have a parabolic shape. Ideally, one could create a part that simply looked like a huge static parabolic dish that would make a stack-attachment above the thermal receiver (to not interfere with its connection to a thermal rocket nozzle), and would provide ThermalPower to the receiver with an effectiveness based on its angle towards the sun... Also, deployable/movable mirrors that could be mounted on trusses away from the body of the rocket, and would angle such as to reflect sunlight towards the Thermal Receiver would work as well- but would be much more difficult to code I imagine... It would produce more thrust for the mass than PV cells coupled with Microwave Transmitters and Thermal Receivers, but of course it would weigh down the craft hosting the mirrors with a (small- much less than a comparable surface are of PV cells) amount of additional mass. Obviously, it would be most useful in the Inner Solar System- especially when sun-diving (simply turn the rocket's tail towards the sun with the static dish I described earlier, and obtain HUGE amounts of Thermal Power for thrust at minimal mass penalty). I could also imagine the ability to reflect sunlight towards a craft over longer distances (using similar coding to Microwave Beamed Power), for much better ThermalPower production than comparable-sized Photovoltaic satellites... (just IMAGINE what a handful of enormous mirror-satellites in low orbit around the sun could accomplish... and without the need for much radiator mass, since +90% of the sunlight is reflected, rather than absorbed) That would be an even more ambitious coding project, however... Regards, Northstar

One receiver can handle an infinite amount of power, but it doesn't capture an infinite fraction of the incoming power. I've tested this many times: two receivers will collect, in total, more power than one receiver of the same size. And larger receivers collect more power than smaller receivers. It caps out at a certain percentage of the total amount of power being beamed at the craft, of course. This increase in total power capture, and design constraints, still make twin thermal receivers useful sometimes- especially on aircraft. Heck, I even use three 1.25 meter Thermal Receivers on one of my rockets as they act as radial boosters around the edges of a HUGE 5 meter chemical rocket core (I'm still using basic fission power- so there's "only" 12.6 GW or so of Microwave Power being beamed at my rockets...) as I couldn't find a 2x symmetry design that fit correctly around my landing legs (it's a Space-X style reusable vehicle: the lower stage is recovered with a powered vertical landing after a straight-up vertical ascent) :sarcasm: Congratulations, you've discovered that basic chemical rockets are crap, and NASA is a bunch of fools for sticking with increasingly-large chemical rockets, when we've had the technology to power our rockets with Microwave Beamed Power since the 1960's... (when the rectenna was invented) The gyrotron-technology used for efficient long-wavelength microwave beamed power has been available since 2005, whereas the technology for short-wavelength power (most likely what is being simulated in KSP Interstellar, based on the relatively high rate of atmospheric attenuation) has been around since the late 1940's... It's a large sunk-cost, but there's no reason we couldn't have set up a large nuclear reactor (or heck, even an enormous solar array, wind farm, or fossil fuel power plant) near the Kennedy Space Center at the end of the Apollo-era, and have begun beaming Gigawatts of Microwave Beamed Power to power reusable rockets (with the higher ISP's achievable- as much as 1000s in vacuum using hydrogen for propellent- thermal rockets are vastly superior to chemical rockets- making reusable rockets EASILY achievable with enough beamed-power to provide good thrust) since about 1970 on... By now, such a launch site would have paid for its (HUGE, multi-billion dollar) cost many time over, from the cost-savings from the reusable rockets (or spaceplanes) it would have enabled, and the fuel-flexibility that thermal rocketry allows... (NASA's annual budget was $20 billion in 2011, to give just one example- and even more in today's money further back in the past- so this definitely would have been within NASA's means to do in 1970...) Regards, Northstar P.S. Don't believe me about the ISP values you can get with thermal rockets in real-life? Take a look at this article on Solar Thermal Rocketry: http://en.wikipedia.org/wiki/Solar_thermal_rocket#Propellants

There's nothing you've done wrong- you've just taken the Kerbal philosophy of "MOAR POWER!" to an extreme... You *DO* realize that you just up a nuclear power array capable of transmitting 15.428% of the United States' annual electricity consumption (3,886,400 Gw-h/yr, equivalent to a constant production of roughly 443.4 Gigawatts), right? Considering the shear INSANE magnitude of a 68.4 GW array, you shouldn't be surprised AT ALL by the size of rockets you can lift to orbit. If we set up a Microwave Array like that in the real world, we'd be lifting 360-ton payloads to orbit like it was a cakewalk too... And once you upgrade, you'll be beaming more than half the United States' baseline power consumption (which is a lot lower than average consumption) to your rockets at any given time, even after the rather massive amounts of power you're losing to the system's minimum 15% inefficiency due to the shear size of your system... It's working as intended. You're just insane- and would NEVER be able to afford a Microwave Array like that once budgets is implemented... :Sarcasm: Really, you think? I'm surprised your rockets don't look like giant heat radiators with the amounts of WasteHeat that must be generating at any given time (15% inefficiency times 68.4 GW, hmmmmm- you're having to dissipate over 10.26 GW of WasteHeat when the receivers are active to keep things from exploding...) NO, attenuation should NOT be higher- it's quite high enough as is (currently corresponding to shorter-wavelength microwaves in real-life: longer-wavelength microwaves need much bigger receivers, but experience less power-loss when passing through atmosphere). There should just be some kind of sanity-check for people like you... I set up around 12.6 GW of beamed power TOTAL, to operate a series of Reusable Microwave Thermal Rockets using a Space-X style strategy for recovery of both the launch and upper stages, which I rationalized could pay for itself many times over in the higher payload fractions and reduced maintenance costs vs. the same fleet of lifters with chemical rocketry, and I thought *I* was overdoing it, and pushing the limits of realism... I'm pretty sure FractalUK based the current caps on what is theoretically achievable with the technologies. However I don't think he planned for players to get ahold of that much power on their spacecraft before they had at least discovered fusion power- by which point the technology might reasonably be thought to have come closer to its theoretical limits. Congratulations, you just achieved with 21st-century technology what probably won't be achieved until at least the 22nd-century in real-life... Regards, Northstar

I didn't realize before that ATO meant "Airship to Orbit". I thought you meant "Air Takeoff" or some other variety of mothership-launch platform, and was ready to dismiss your post the same way the one I did earlier about mothership launch platforms (don't get me wrong, mothership launch platforms are a GREAT use of current technology and resources, certainly an improvement over conventional launchpads at sea-level: but they're NEVER going to cut costs to the levels we need them to unless combined with something like Microwave Beamed Power and 100% reusable rockets...) This is why you REALLY need to always define your acronyms... Yeah, Orbital Airships (or Airship-To-Orbit) are a pretty great technology. They're particularly good with Microwave Beamed Power, since the airships accelerate slowly and are thus easy to track. They also can get by with a much lower TWR than a spaceplane or a rocket, which means you could get a MUCH heavier payload to orbit with, say, 200 MW of beamed power for an Air-Augmented Thermal Rocket on an Orbital Airship, than you could with the same thermal rocket on a spaceplane or rocket... 200 MW of Microwave Beamed Power is enough to get a multi-stage thermal rocket carrying a couple nanosatellites to orbit. Or to keep an aircraft with low wing-loading in the sky using Thermal Turbojets with an altitude ceiling roughly comparable to a B-52 Stratofortress (though the Microwave Array alone would cost about $200-400 million using 1 MW units: as much as four to eight B-52H's...), as Thermal Turbojets can obtain much better thrust for a given amount of Thermal Power than a Thermal Rocket, due to their low exhaust velocity and high working-mass... (and an aircraft using them doesn't have to carry any fuel, only a thermal power source, such as a nuclear reactor or Microwave Receiver!) I don't include any figures on spaceplanes, because there haven't been any built in real-life, aside from VTHL designs piggybacking or riding in the nose of disposable or semi-disposable rockets (like the Shuttle or X-37) However, that same 200 MW of thermal power could provide consistent acceleration to an orbital airship, at an ISP of approximately 1000 seconds with hydrogen or 650 seconds with ammonia (which is more easily stored without boil-off on the high-altitude aerostat station than an Orbital Airship would depart from, and is also space-storable) on a pure thermal rocket, sufficient to eventually bring a MUCH larger payload to orbit in a single launch. The ISP figures come from the Wikipedia articles on Solar Thermal and Laser Thermal propulsion: http://en.wikipedia.org/wiki/Thermal_rocket If you made use of an Air-Augmented Thermal Rocket, you could get EVEN HIGHER ISP: your exhaust velocity would go down, but only a portion of your working mass would actually come from internal fuel reserves (similar to how a turbofan engine has high ISP, but low exhaust velocity), so your "Effective Exhaust Velocity" would actually go UP... http://en.wikipedia.org/wiki/Air-augmented_rocket It's worth noting that you might be able to operate the Orbital Airship purely off Thermal Turbojets powered by Microwave Beamed Power, for essentially *UNLIMITED* ISP (as the propellant is the air around the ship) in the lower part of the ascent to orbit, before the airspeeds became too high and the atmosphere too thin for a Thermal Turbojet to any longer be effective, and you had to switch to Thermal Rockets... In short, an Orbital Airship would GREATLY increase the payload you could lift to orbit in each individual launch using Microwave Beamed Power. The beamed power could additionally be augmented by thin-film solar cells sprayed over the envelope of the airship (all that surface area is generating drag- might as well also put it to good use generating electricity for the airship) used to power, in order of increasing altitude ceiling and decreasing TWR: electric propellers, solar Thermal Turbojets, solar Air-Augmented Thermal Rockets, solar Thermal Rockets (same ISP as Air-Augmented Thermal Rockets in vacuum conditions, but with better TWR), or solar-powered Ion Engines. The cost of using this approach is that you wouldn't be able to launch as many payloads a year this way as with pure Microwave-Powered Thermal Rockets (no "3000 launches a year" using Microwave-Powered Orbital Airships- but the payload carried with each launch would be MUCH heavier). So, it's a question of fewer, heavier launches vs. a larger number of lighter launches, for the same payload to orbit. The preferable method would have to depend on the payload you want to get to orbit each year, and how much Microwave Beamed Power you provide: there's an optimal balance between the greater-efficiency of heavier launches (better ballistic coefficients, less man-hours at the control center, less mass wasted on guidance/navigation and other control systems, better ISP of larger rocket nozzles near sea-level) vs. the economies of scale of smaller launches (smaller rocket nozzles also get better vacuum ISP- though you can achieve the same effect on larger rockets with engine-clusters of many smaller nozzles...) OK, I've said enough for now. I'll have to remember to add Airship-to-Orbit to the Original Post, though... Regards, Northstar

Like you said, it's very easy to track a relatively slowly-accelerating blimp as it attains orbital velocity with microwave transmitters compared to a rocket... The beauty of using orbital airships in combination with Microwave Beamed Power is that you can get a much heavier payload to orbit with the same amount of available beamed-power, or the same payload with less power, this way, since orbital airships don't require as high a TWR as a rocket or spaceplane (the buoyancy and lift prevents the vessel from simply falling back into the lower atmosphere, and allows all the thrust to be directed horizontally rather than vertically). Somewhere like a new Venus colony, where resources are likely to be even MORE limited than they are here on Earth, would benefit greatly from being able to get their payloads to orbit without having to maintain as powerful a system of Microwave Beamed Power this way... Regards, Northstar

Well, as always, the truth is more complex than I initially anticipated. Here's what I found after doing some research: it might be interesting to this mod: It turns out that, in vacuum and high-altitude flight, you want a LARGER nozzle cone relative to the enclosed area of the rocket nozzle and the size of the engine. To the point that there are actually patents for "extendable rocket nozzles" specifically designed to enlarge rocket nozzles as a rocket climbs in altitude... However, at lower altitude, a SMALLER nozzle is desirable, so as to prevent atmospheric pinching of the exhaust column. Aerospike engines use shock waves rather than changes in nozzle size to obtain optimal ISP throughout an ascent. What all this means for rescaling engines: Larger rocket engines of the same nozzle design have relatively smaller nozzles (as area of a circle = pi * radius^2, whereas circumference = 2 * pi * radius), and thus should obtain better ISP near sea-level, but inferior ISP at altitude. Smaller rocket engines of the same nozzle design have relatively larger nozzles, and thus should obtain better ISP in vacuum, but inferior ISP near sea-level. IN SUMMARY: What seems most appropriate (accurate/realistic) is not to blanket-cut ISP across-the-board for scaled-up rocket engines, but rather to shift their ISP curves slightly so they perform relatively better at sea-level and relatively worse in vacuum. As it so happens, that also corresponds best to how players will normally use larger rocket engines- for lower stages of atmospheric launches. Isn't it nice when things just work out the way they should? Tough luck for people looking to use a mod like this to scale up engines for reusable rockets in vacuum conditions, like I am for my planned Mun base, though. Regards, Northstar P.S. For those of you who didn't catch it, there following link was embedded in the post: http://www.google.com/patents/US4787559

Just a thought, but IRL, shouldn't ISP and TWR *INCREASE* when going to a larger diameter, regardless of what they do in-game? This would seem intuitive, since the amount of mass to make some parts of a rocket engine, such as the rocket nozzle, would decrease relative to the mass of the rocket engine when going to a larger size (a 2 meter circle has only twice the circumference of a 1 meter circle, but encloses 4 times the area), and the exhaust column of a wider rocket nozzle should be less subject to pinching or pluming compared to that of a smaller nozzle (see this article for a simple explanation of what I'm talking about), once again due to its better ratio of cross-sectional area to circumference... Regards, Northstar

Glad to have you onboard Marco! I hope you enjoy the game! Now get out there and launch some rockets if you haven't already! And remember, you can never have too many boosters! Regards, Northstar P.S. This is a shameless plug, but once you get familiar with the game a little, have landed a couple Kerbals on the Mun perhaps, and want to start dreaming bigger, feel free to take a look at my thread (http://forum.kerbalspaceprogram.com/threads/57509-Kerbin-and-Beyond-a-Maturing-Space-Program) for some ideas. Also, I'll be starting a new save from scratch soon with 0.24, maybe a week or two after it comes out (and some of the mods I've played with have updated to it), and documenting it from the *very beginning*, so that'll be an interesting tutorial in the early game if you haven't found much time to play KSP by then...

Whee, another update! Seriously though, progress continues. First of all, my LFO Tanker reached my Munar Spacedock and transferred over its fuel. My Kerbals also ripped off its OX-STAT solar panels, but I discovered that the Skycrane + ISRU Refinery had drifted too far away (10 km) for the Kerbals to easily EVA over and attach the panels without the aid of a navigational system. So I'll have to either wait until it drifts closer again (that *might* take a while) or have the panels and a Kerbal hitch a ride on the next ship to come through the refueling station... Second, I launched the first component of my mission to Sentar- the Sentar Mission/Return Vehicle. It launched first since it has a nuclear reactor (for electricity and propulsion out at Sentar distances where my Microwave Beamed Power network won't reach, and sunlight will be EXTREMELY weak, thanks to KSP-Interstellar's accurate implementation of an Inverse-Square Law for stellar radiation...) and two Microwave Beamed Power Deployable Transceivers- which allow it both to receive beamed power to help maneuver, and beam its excess power to other ships to help them get off the ground on Kerbin while itself sitting idle in orbit. The Sentar Mission Vehicle forms the heart of my Sentar Armada- its reactor will be beaming power to all the other ships for both electric/thermal propulsion (plasma engines and thermal rockets) and routine SAS/navigational use. It's an idea I'd been playing with in my head for a while, and it'll be interesting to see how it works out for this mission. Though, at a peak of only 54 MW of beamed power it can transmit to other ships (for short periods of time, until its reactor starts running hot and power output declines), it won't exactly be the (comparable) walk in the park using the system that maneuvering near Kerbin has become... I'm thinking I should have packed a bigger reactor. Third, my Supply Ship made its first aerobrake pass on Kerbin. Although mildly unrealistic, I might not load it up so physics apply for every pass- I have other things to do than waiting on this $@$% in-game, and the Supply Ship has nowhere else I need it to be since it turns out the Munar Spacedock is thoroughly and completely bugged when it comes to constructing other craft in-orbit. Luckily, Extraplanetary Launchpads' ground-based launchpads work fine, even if its space-based ones are still buggy for anything more than small probes- so eventually I'll land a launchpad on the Munar surface and ferry the RocketParts from the Munar Spacedock to the ground-based launchpad. Unfortunately, that will add greatly to the inefficiency of the whole process, as it will force all my rockets to interplanetary destinations to launch from the Mun before heading for their eventual destinations- adding greatly to rocket fuel and mass requirements. It's not the most realistic either- as theoretically it's easier to build big, bulky rockets in zero-gravity than on a moon's surface (although neither has actually been tried in real life AFAIK...) Next on the docket, the debris from my probe-launch towards the Sentar and Inaccessible systems before crashed into the Mun, generating !SCIENCE! Finally, my second Hydrazine ATTILA probe made a burn near the Mun. I know I originally talked about circularizing it and topping off its fuel there, but not only did I realize this would this be *EXTREMELY* inefficient (as it only spent 3 m/s of fuel since separating from its earlier stage), but I also discovered that I could easily set it to Kerbin-dive such that its periapsis would be properly set up for an ejection-burn towards Sentar- the ejection angle for which should ideally be approximately 161 degrees-to-prograde (according to the Launch Window Planner once programmed with values for Sentar). I will probably also be placing this probe on a trajectory that sets it on an escape-trajectory from Kerbol (much lower-speed than the other probe, but still eventually escaping the sun's gravity), thus allowing it to turn around and make a flyby of ANY body in the Kerbol system. I'll have to decide at some point where it's headed though... If it heads to Sentar, I might choose to aerocapture it there and have it wait for the remainder of my Sentar armada- its Hydrazine can also be used as fuel by the plasma thrusters of the other vehicles in the armada- although it only has Jr-sized docking ports, so I will have to remember to launch at least one vessel with appropriately-sized ports if I want this to remain an option... (or a KAS winch and an extra radial adapter- to basically drill a hole into the side of the probe and drain it's remaining Hydrazine...) Regards, Northstar

Delta-V would take some seriously hard math (which I'm really not familiar with). But here are the mass, radius, sidereal rotation period, Semi-Major Axis, inclination, and eccentricity values for each planet, which should give you a rough idea: Ablate mass = 8.94276895415044 E^18 kg radius = 13 km sidereal rotation period = 159300.265559099 seconds (2655 minutes- I *think* that's tidally-locked to the Sun) SMA = 910,000 km eccentricity = 0 inclination = 5.0 degrees Ascension mass = 1.90144081510339 E^19 kg radius = 14 km sidereal rotation period = 4040 seconds (67.3 minutes) SMA = 100,000,000 km eccentricity = 0.97 inclination = 19.0 degrees Inaccessible mass = 3.96868444710818 E^18 kg radius = 15 km sidereal rotation period = 440 seconds (7.33 minutes- NO THAT'S NOT A JOKE) SMA = 125,000,000 km eccentricity = 0.01 inclination = 2.0 degrees Sentar mass = 5.09314680671058 E^23 kg radius = 6,000 km sidereal rotation period = 36,000 seconds (10 hours) SMA = 160,000,000 km eccentricity = 0 inclination = 26.0 degrees Skelton (Moon of Sentar) mass = 4.51548115036107 E^21 kg (identical to Duna) radius = 320 km (identical to Duna) sidereal rotation period = 65517.859375 seconds (18.2 hours- identical to Duna) SMA = 50,000 km (from Sentar) eccentricity = 0 inclination = 160.0 degrees (yes, that's an inclined retrograde orbit) atmosphere: sort of (3 atmospheres THICK at sea-level in the valleys, but does not reach to the top of the mountains) oceans: no Erin (Moon of Sentar) mass = 2.9397663009231 E^22 kg (identical to Laythe) radius = 500 km (identical to Laythe) sidereal rotation period = 21600 seconds (6 hours- much faster than Laythe) SMA = 80,000 km (from Sentar) eccentricity = 0 inclination = 15.0 degrees atmosphere: yes (probably oxygenated) oceans: yes (like Laythe) Pock (Moon of Erin- yes, that's a moon of a moon) (coming soon) Ringle (Moon of Sentar) mass = 4.23326347332927E+22 radius = 600 km sidereal rotation period = 491383.972112887 seconds (136.50 hours- darn that's slow!) SMA = 120,000 km (from Sentar) eccentricity = 0 inclination = 15.0 degrees atmosphere: no Thud (Moon of Sentar) mass = 1.66155588852263 E^23 kg (that's 32.623% of the mass of the gas giant it's orbiting!) radius = 600 km sidereal rotation period = 1751403.30360751 seconds (20.27 days! With surface gravity that high, don't try landing here!) SMA = 280,000 km (from Sentar) eccentricity = 0.25 inclination = 20.0 degrees atmosphere: no Regards, Northstar