Newt

Solidworks is looking, to me, to be the best option; there would appear to be several formats that we can import and export between (I am not certain of all of their capabilities) between the different software we have been discussing, but importantly, we have access to simulations, through delijr15, above and beyond what we otherwise would have access to. That alone, might be reason to go that route, for those simulations will be likely very valuable in analyzing our satellite's behavior, and thus designing it better. If we can edit it in other software, that would be great, but I think the access to those simulations should be paramount. Greetings DarthWahl and Vetrox! Glad to have you onboard.

There are other proposals for the dichotomy between North and South on Mars. Giant impact, for instance. I am not really sure that simply wetness would explain the full difference between the two halves of the planet. Something caused a difference, but I really do not think that oceans are widely taken as an answer. Maybe that will change. P.S. You are not alone in recognizing that sort of thing here:wink:, Upsilon.

Yeah. It is essentially the force (okay, psuedoforce) that enables an orbit. You can do calculations for orbital period and that sort of thing using the same equations as for centrifugal force, although with non circles, complexity builds.

I will be sure to see it. I also can try to help if you need it, but am unsure of regular avaliability. (Rather I am sure of irregular availability).

No it does not. It is to me looking as though we may well be able to transfer files between Sketchup, Solidworks, and Blender (which I use). We just need to test it and see.

We should probably be somewhat easy on Nicholander; this would seem to be his first ever model in this software, and it was put together pretty quickly. But it is helpful to look at nonetheless. It really is such a small space that the magnetorquer needs to be either up against the computer or the cameras or the radio or all of them really, 10cm^3 is tiny. I have been wondering about the heating system. Might not the computers/magnetorquer not only heat up the satellite, but bake it if we are not careful? I am uncertain that we will need something specific to keep the thing warm, considering the hardware we have already. We might really need to be looking for where to put the radiators.

That looks mostly fine to me. Are you basing it on actual proportions or general guesses? I threw together a quick Blender model based on your image, but I guess that I need an imgur account or something to that effect to post pictures here.

That looks like sketchup to me, Nicholander. Do you mean of all the things decided, or all the things needed? I would say your model need to have batteries, maneuvering control of some sort, solar panels, et cetera. But, I guess it has the essence of the design as I know it. (Opening a new scene in Blender).

The torquer sheet comes after the weight volume title, and vice versa.

Well, about Solidworks, though I am sure it is a valuable tool, it looses out to Sketchup in the vital area of cost. And it is easier to learn than other free 3d software (Blender for instance), albeit more basic. (Anything, is better than drawing in MS paint:rolleyes:). As for price, the value I cited may have also included the cost of labor, which we are not dealing with here, and other similar cubesats may also circumvent with volunteers. And placeholders certainly make the total cost value a number to eye carefully. It will change very much in the future. About the computer, the Raspberry Pi is not going to be on all the time, and mostly will deal with data transmission and gathering, won't it? It will remain off most of the time, so power concerns about it can be limited. MBobrik: I think that the URL's for spreadsheets that you linked need to be switched.

You do not need number tables, you need equations. It will save your code a good deal of space, as you can use the same essential algorithms for each object, not just Kerbin but all the planets and moons in the system. There are many good books on the subject of orbital mechanics, and I am sure people here can help with the math if you need it.

That, is a difficult one, RobotEngineer. There are a couple of things that make it so. We know that it got to Saturn, that it entered Saturn orbit without apparent aerocapture, and we know that it took about two years to do this. It is possible to calculate such an orbit, and how much ∆v is needed to do so. Off the top of my head I have not calculated that, but let me tell you that it is a lot of acceleration. Cassini spent seven years going to Saturn, and slower most often is cheaper. When it gets really difficult is when they go through the wormhole, on the water planet the ship did station keeping for about 20 years. That is not much, but I am sure it adds up, and without good information about the local environment, ship's interaction et cetera and drag parameters, it is essentially impossible to do. Further, they fly about between these different planets, of unknown orbital parameters, of to us unknown positions, and around a black hole, the mass of which we can speculate but not know for sure. We also do not know how efficient of orbits were used for this purpose, although aerocapture and gravity assist maneuvers appeared to not be performed. Finally, they somehow blasted themselves into a doomed orbit around the black hole, after the horrible docking event. This changed the mass of the ship, may have cost them fuel, and probably impacted performance to some degree. But really, that does not make that part of the calculation any more difficult, we knew so little before. Other ways to do it seem difficult to do. We know neither how much fuel they had, nor what sort of fuel it was, really. It did not seem to be nuclear, or ion, but perhaps chemical of some sort. But who knows? We may be able to estimate a lower limit of the ∆v, by adding up some actual numbers and estimations, but I think that really the film gave us too little information to do something that can be answered with any certainty. Thus in sum, the Endurance had a ton of ∆v. More than any spacecraft to date. But how much is a very speculative matter. I think that your best bet is to peer at some screens during the film and try to see if any of them give better data than the audience was given directly.

Well, no. Time from the perspective of a moving object constantly adjusts itself such that the speed of light relative to that moving object is constant. Though it is impossible, a hypothetical spacecraft (or bouncy ball ), moving at the speed of light, would perceive time to stop. This would mean that between the bouncy ball and a hypothetical photon near by it (or on the other side of the universe), there would be no increase or decrease in distance at all. But that would have to be taken with the understanding that no time has elapsed for the bouncy ball, so the distance (0m) divided by the time (0s) really does not go at all against that limit of velocity, as velocity's measurement mandates the passage of time. You could do the same evaluation for me sitting at my computer. If time were to freeze, the distance between myself and any photon would remain constant and static. @Otis: N_Las provided a few good sources for you. You have to remember for this, that we routinely accelerate particles to nearly the speed of light in particle accelerators. @Derpen Wolf: That is an interesting thought. I am thinking it might have something to do with the time dilation, and an apparent mass change not a physical one. But I am thinking about it, and would be curious for any other ideas.

If I get the question right, it is not asking about the symptoms, of increasing mass, or nonavailability of infinite energy, rather about really why. Why does the mass increase with the velocity of an object? Why does the Universe pay so much heed to that one speed? I agree that there is a possibility of getting very deep into this, and trying to evaluate why with fancy maths and theoretical physics, but the real answer for now is probably best that no one knows. We have evidence that it does this, it makes sense based on many experiments, based on much observational evidence, but ultimately it is yet unanswered. Then again, you can also maybe be satisfied by the idea of multiple reference frames. You can go faster, and a ship that fires its engines, launching from another ship will be going clearly slightly faster to both parties involved, the one at .9999999c, and the one at .9999998c. Time will just be going differently for the two vehicles, and for the people watching from a nearby star system, making it look to each, as though relative to them, c is constant.

Well, the NASA CubeSat Initiative page (linked in the OP) says that they weigh ''about three pounds''. That concurs with mass limitations on pages linked by that page (the fact sheets): No more than 1.3kg per 1U cubesat. Of course, if we want to reduce that to less than that, it is up to us. But we are not the ones launching the thing; we get no more control over our orbit by dropping mass. Many thanks for the table, MBobrik, it seems to put this in a lot better perspective for me. And, Nicholander, so far that is about 91,330USD. Bear in mind that that fails to account for many parts, and that at this stage many of the costs are as far as I know, conjecture. I have heard that a common lower threshold cost for one of these is about 250,000USD.

That sounds fun. My fist interplanetary flight was a trip to Jool, using a tiny ion drive probe, in .18. Needless to say, there were no Kerbals onboard, as the ions were too weak (and it was a secondary payload anyway). Welcome to the forums!

I am pretty sure the shuttle ones had been previously painted white (why I do not know), but the decision was made to leave them orange, as to save mass.

Well, the first post I made was in the Orion Launch thread earlier this week. Need to figure out how to post images still, but I had intended to add an edited view of Bill, Bob and Jeb in the corner of one of the digital animation views. But the first thread that I really remember was a page for a mod with an absurd number of absurd engines mostly. Engine nozzles thirty meters tall, brightly painted purple, or designed to look like warp nacelles. It was, interesting, strange, and a fun bit of exposure to what could be done with the game, so I came back. I imagine it was lost in the Great Kraken Attack of April, and I do not recall seeing it again.

There was a study in the late sixties (I believe the sixties) that examined the possibility of blocking an object (not as big as Pallas) from an impact with the Earth. The conclusion was centered around the launch of several Saturn V's (those were the days) armed with nukes. These would fly close to the object, and detonate at a range so as to dislodge a large mass of presumed regolith from the surface, as reaction mass. After each detonation, the results would be examined, and plans tweaked to ensure that they do the course change right, and as a last ditch effort, there was the possibility of blasting the thing to bits, and hoping that most of it vaporizes. We no longer have the Saturn V's, of course, but advances in propulsion technology, computer technology, and nuclear weapons technology might would simplify this deflection. Also, they were saying that there was one year, not four.

Okay everyone. Pictures are (if all goes well) coming. The adventure described above was two years and one computer transfer ago. But my space agency's archivists are packing their bags for a long expedition to the catacombs. We will see what they turn up with.

It is essential to look at how these things will all work together, though. Mr0nak raises a good point in that we should be well, a little more down to earth. All of the parts will interact, and if we at least had a basic sketch of what the hypothetical satellite looks like, how big everything should be inside of it, and a ballpark guess of what it will mass, that would keep things a bit more in perspective, and keep us from wandering too far from possibility. Maybe it can even give us some ideas? I would be willing to try to put together a model of all of this, but really do not know if there is enough decided on at this point. Perhaps we should try to get that sorted out, so if we are too big, we figure that out sooner rather than later. The document linked at page 1 has a list of parts more or less, but does not get into size, really (yet). EDIT: Mazon, I was addressing the proposal that the ring itself spin, which seems mostly to have been shot down now. I had the page open for a while, and got somewhat lost in what was being said while I was not pressing f5. Still trying to sort out all the order.... Regarding gforce changes during camera spin, it was said that we would probably be spinning very fast (more than 50RPM). At .05m radius, at 50RPM, we should have about 1.37ms^-2, at 51RPM, 1.426ms^-2. Not too much difference, but worth noting. Also, as has been mentioned, we can take our time taking pictures and swiveling the camera, so 1RPM might be excessive. If you are refering to just the speed increase for the ring, my understanding is that the ring will be affected by the satellite rotation. But again, we are usually in no hurry to orient. One issue I just thought of was that of our Center of Mass. If that is not spot on, we might get serious gravity differences from what we had hoped for.

I have been here posting for a few days only now, but I have been here reading for about 25 months. Yes. I got KSP in November 2012, visited this forum soon afterword, and have visited with fair regularity for about two years. I saw the Great April Purge, and all of that, but never posted. So now that is changed. For this thread, I thought I would post a story, as that seems a fine introduction: As I said, I got KSP in 2012. At that time the game was in several ways different, no career mode, for example. My first launch to orbit was mostly complicated by one thing. SAS. Kerbal computers at the time were less sophisticated than now, and SAS would be installed through a separate module. My first launch vehicle, by oversight and inexperience, had no such module. So my first launch attempts featured screaming Kerbals for a few hundred meters, who soon fell down to the ground on parachute. I was stubborn, and did not look too closely at the rocket, for I knew that it could make it to orbit, probably even to Munar orbit, from its size. And though I knew the concept of SAS, I did not know to add any. So I persisted. Progressively, the altitudes reached increased. I would spend my time dancing my fingers across the keyboard, almost not needing to check the fuel levels as I flew the rocket so many times, I knew when to eject the stages. I tried rolling the craft to maintain orientation, and it ended up spinning over. I tried flying in different directions. With different throttle settings. And most importantly just kept launching and practicing. From the ground, flights would be done in map mode only. I would watch the navball in exclusion, and check the fuel levels with my peripheral vision, staging when the acceleration dropped. I would check the altitude on occasion, and in some flights that would result in a loss of control, and abort. So I did it rarely. But eventually, as my fingers raced between the keys, I reached higher than before, gravity turn in progress. I watched as the pe flew up over 70,000, and as orbit was achieved. It was really fabulously relieving, and I let my concerned Kerbals (no longer Bill, Bob and Jeb, alas) float around for a few orbits, before the deorbit, which I was convinced would be their doom. Of course, it was surprisingly easy, and may concern was unfounded as the slowly dropped down in the ocean. I have other stories, my first commsat, turned Mun lander, turned Laythe orbiter. Or the time I discovered brakes, as a spaceplane landed less than 50m from the water. Or the time that I walked clear across the KSC continent. But I will save those for later. For now, Hello!

Mazon Del, Using servos to spin the thing also seems to pose several problems. For one, we will be pushing off of the rest of the vehicle, using it as reaction mass. We will thus need to hold it back from spinning by some other means. Additionally, the equilateral triangle design and the servo will, unless we get some way to disconnect, have a continual friction, imparting force to the main body, and slowing itself down. That will mean that much of the time we will need to have the servo running, just to prevent the centrifuge from stopping its motion. That will risk problems of heat dispersion, as we don not want baked moss and computers. So we need an exceptional servo, that can run for the duration of the primary mission with few if any pauses, and that puts out extremely little heat. Plus we will need to have an outer body control system that can deal with that force at all times, lest the satellite spin out of control, loosing radio contact and sunlight. Taking a photograph from a non-rotating camera of such a fast rotating target also seems to be of concern. If we are rotating at 100RPM, and taking a 1/300second exposure, the target will have spun 2 degrees before the shutter closes. That is pretty unacceptable, I think. How bright will the moss be lit up? I saw something about the possibility of a basic moss experiment trial, did that happen, how did it go?

Even if it were practical, which I highly doubt, we do not have a suitable lunar vehicle already designed, and for our interests here, the design of that vehicle would almost certainly take longer and be more difficult than an ordinary lander. To the 787, I am not sure exactly what you mean by dull and dangerous, especially if we could stick in a Venus flyby too, which has been the plan since the 60's. The next launch window:2021. Apollo VIII, was by no means dull.

Henryrasia: That makes sense, but I would be concerned about the influence of drag between the two parts, as well as the communication between the two. It seems likely that we would continually need to push the centrifuge faster, as it would impart its force to the main body, which would have its own need to counter the imparted velocity. It might work, and certainly if we could then use a passive means to point down we might ultimately save some power. But that fails to address the solar panels. We would also need a means of communication and power transfer most likely, which could be established by, for example, metal contacts along one axis, but I am unsure of reliability. Bounding Star, I would be most concerned, not about the moss' well being, but about the satellite. Moss is pretty resilient, from my experience, but being mashed and broken and shaken. Delicate wire connexions, not so much. MBobrik, there are several schemes to how to arrange your comm network, based on orbital inclination as well as a how you want to communicate with the satellite, many short windows, fewer long windows et cetera. Full equatorial coverage gives two windows/orbit, for example, whereas full 51N coverage, say gives only one, but takes fewer stations, and there are many more. Alas, this is really a discussion that can not go very far, considering that where we have the opportunity to establish a comm station, is really not up to us.