Snark

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Everything posted by Snark

  1. Not sure which "you", or which "it", you're referring to here? And are you in favor of having something dramatic happen when the craft passes Mach 1, or not? My own position on the matter is: Frankly, I don't care all that much about Mach 1 per se. I can live without any special effect that happens at the transition. But I'm also fine if they wanted to put one in. That said, I would not be fine with a ludicrously unrealistic, this-never-happens-even-in-movies effect like a "bang" right when it happens. If they did go with something, I don't need it to be hyper-realistic, just not laughably unrealistic. My favorite suggestion that I've heard thus far is @monstah's, since I gather (from my extensive research, consisting of watching The Right Stuff) that things get shaken up a bit as the craft's about to transition, and camera-shake would capture something of the flavor of that.
  2. You send energy in, you get totally random stuff out when it decays. If the energy you send in is modulated-- i.e., data-- then that's just gone. It's not as though the black hole remembers what the data was. Oh, I dunno. Given that the signal takes 1600 years to cross the distance anyway, it's probably okay if the message itself takes a decade or two to complete.
  3. There's no limit to how much power you transmit; you can spray as many or as few photons as you like. If you've got a kilowatt transmitter... or megawatt... gigawatt... terawatt... petawatt... no problem. However, there is a limit to how sharply focused the beam can be, due to diffraction. This is a function of the ratio between the wavelength of whatever you're sending (be it radio, microwaves, visible light, whatever) and the diameter of your transmission apparatus. Discussion here. For a circular aperture, the best you can do is a half-angle spread in radians equal to 1.22 times the wavelength, divided by the diameter. That said, if we're talking a distance of 3000 light years, I think that's doable with current technology and engineering. I forget the exact numbers, but I seem to recall reading that if we used the Arecibo telescope to transmit a message directly at another Arecibo-equivalent telescope pointed right at us, the max range would be something significantly bigger than that. ...did you leave out some zeroes somewhere? We've seen stars a whole lot farther than that. ^ I think that complete inability to send any information across it is kind of what the Schwartzchild radius is about.... Yes, but I don't think 3000 light years is all that un-doable. That's a small percentage of the width of the galaxy, and my impression is that two Arecibos pointed at each other could communicate across that distance. They'd have to be kinda patient, of course, but I don't think anyone's proposing this as a Netflix subscription mechanism. *rummage* *rummage* Ah, here we go. http://www.setileague.org/articles/oseti.htm Even the pessimistic estimate in this paper gives a communication range between two Arecibos as being on the order of 10,000 light years. The optimistic estimate is 26,000. So yeah, 3000 seems doable.
  4. Now that's a neat idea! Really like it. Done right, it could be very immersive to the player-- satisfies the "Hollywood factor", while having a close enough relationship to reality that it doesn't stick in my craw. Could make the "Mach shakes" proportional in some way to the atmospheric pressure, so you get shaken hard at Mach 0.99 near sea level, but it's a lot milder if you're doing it where the air is a lot thinner. I like the idea of a visceral "I've broken through!" feeling when the shakes suddenly smooth out to a continuous dull roar as you pass through Mach 1.
  5. Or maybe kerbals are actually blue (or red, or purple...), and it's just that there's an economically robust cosmetics industry on Kerbin that has managed to convince everybody via a dedicated decades-long marketing campaign that Green Is Beautiful. "There's no beautiful like KerbCorp beautiful! If you're not using KerbCorp Algae Cream to 'release your inner green', you're not looking your best!"
  6. Protective coloration? Mating display? Poor hygiene? There are plenty of green animals. Just not any photosynthetic ones.
  7. Not impossible. Just very, very improbable.
  8. And also pointless, from a scientific point of view, since if he wanted an omnidirectional broadcast across the galaxy, he might as well just broadcast omnidirectionally. Sure, if it's a marketing stunt, "mumble mumble black hole mumble mumble" sounds pretty cool, and there's nothing wrong with that. But if all one is interested in is sounding cool without any scientific justification, why bother asking here in the first place? Sure, for an observer who happens to be sitting in exactly the right spot. And, by extension, observers outside of that spot would get less of a signal. Since the volume of space where the signal intensity would go down is vastly, hugely, literally astronomically bigger than the volume of space where it would go up, then on the whole, beaming towards a black hole would be a net negative if your objective is to get somebody to receive the signal. The original post I was responding to, though, didn't say "focus"-- it said "amplify", and also used the term "slingshot", which seemed to be implying that the black hole would actually be adding energy to the signal, which is not the case. It also was saying that it would scatter the signal (which it would), which is the exact opposite of focusing, and would make the signal harder to receive. And the post was saying that a black hole would be a good target, whereas it would actually be a direction best avoided.
  9. Nope. Scatter, yes. Amplify, absolutely not. That portion of the transmission that doesn't actually intersect the Schwartzchild radius can get bent every which way, but it's not really any different than if it hit a curved mirror. And if you wanted an omnidirectional broadcast, why bother focusing your initial transmission in the first place? Certainly the black hole wouldn't add any energy to the signal simply by virtue of passing by it. The light would gain energy falling towards it, then lose that energy as it recedes again. It's not as if the light beam is performing an Oberth maneuver, or something. At most you might get some dopplering up (or down) if the black hole's motion relative to you has a significant radial component, but again, that's not any different than if it were a mirror moving towards or away from you. Scattering = not concentrated = lower signal strength = harder to receive. So it would do the exact opposite of "amplifying".
  10. Nope, not to any degree that matters. Remember, we're talking multiple orders of magnitude here. Photosynthesis does not work for animals. Really. Not even close. If it did, they'd be doing it already. If a kerbal were human-sized, but shaped like a thin sheet of paper so they had a human's surface area but weighed only a few ounces, and if they went around completely naked and spent all their time sunbathing, then they could live on photosynthesis, as long as they lie still all the time and never move. But then they wouldn't be a kerbal anymore, they'd be a banana leaf.
  11. Sure, in the sense that they get 99.9% of their calories from "snacks" and 0.1% from photosynthesis. Any contribution that photosynthesis makes would be an insignificantly small amount. Photosynthesis has a very low energy production rate, relative to animal metabolisms. We're talking multiple orders of magnitude, here. It's just not meaningfully possible for a large multicellular animal to generate any significant proportion of its own food supply via photosynthesis. There's a reason plants just sit there and don't go walking around. Unless, of course, you want to get all sci-fi with it, such as
  12. Well, not really. It can only be received by a mobile device that's already in front of the signal, which of course excludes you or any other person who was around at the time & place of transmission, because the signal is fleeing from all of us at the speed of light and therefore none of us can never catch up to it. So you'd basically be limited to some hypothetical alien being that, 1. is in the right direction to receive the signal, 2. is far enough away that it's already in front of the signal when the signal arrives, 3. happens to be listening, and 4. can figure out how to decode the signal. But within those limitations, sure. ...yes... but thus the question, why a black hole. As opposed to just beaming it towards some random point in the sky, or towards a star cluster, or something. Sending data into a black hole is sending it to literally the worst possible place in the universe if you want it to be received by anything. It's basically the equivalent of being on a desert island and wanting to send a "message in a bottle", so I write the message down, then burn the paper and grind the ashes into powder and then put the powder into a blast furnace to decompose it to its individual molecules. Very dramatic, sure, but not super effective as a way of getting the message to anyone.
  13. Some very detailed explanations above ... but just to summarize in case this important detail got lost in the shuffle: it doesn't matter which one is more powerful. Because a better antenna is more powerful to transmit, but also more sensitive to receive. It's symmetric. To find the max range at which two antennas can communicate with each other, it's sqrt(A*B). That is, take A's power, multiply by B's power, and take the square root of that. That's the max range, for communication in both directions. You can boost the antenna power of a vessel, somewhat, by stacking multiple antennas. The Communotron-16S doesn't stack. The Communotron-16 stacks linearly (that is, if you have N of them on a vessel, it's N times more powerful.) All other stock antennas are stackable, but with diminishing returns. If you have N of them, they will be N0.75 times more powerful than having just one. There's an enormous quantum leap in power from the HG-5 to the next level up of antenna; it's a factor of 400. So you can use the HG-5 for exploring Mun and Minmus, if you have a direct LOS to Kerbin. If you stack a few HG-5 antennas, then you can communicate from one ship to another between Kerbin and the Mun. But that's pretty much it-- you need better antennas to go interplanetary.
  14. Alas, the math on that just doesn't work out; there's simply not enough energy available from photosynthesis to fuel a critter that can move around on its own power. And by "not enough," I mean not enough by orders of magnitude, even if you make some very generous fictitious assumptions about the efficiency of kerbal photosynthesis, or the radiant flux of their sun. There's a reason why plants have elaborate fractal shapes and very thin leaves to generate scads and scads of surface area for the least possible biomass, while having a metabolism so slow (relative to animals) that they just sit there unmoving. And why the biomass of plants in any ecosystem has to be many orders of magnitude bigger than the biomass of animals that it can support. Photosynthesis is hard.
  15. ^ This. I do it for two reasons: I don't want a TWR that's too high, since that can lead to problems such as wasting dV to excessive aerodynamic drag, or hitting plasma blackout on the ascent and losing control of my ship (if it's uncrewed). I generally like to take off with a TWR that's exactly the same for every rocket. It makes for predictable launches-- I start my gravity turn right off the pad, and if the rockets all have the same TWR, it makes it a lot easier to decide how many degrees to tip so that I nail the gravity turn just right. So I tune my SRBs, and leave liquid-fueled engines alone.
  16. Yep. The thing that's confusing you is that the tracking station on Kerbin is so much stronger than any of the low-end antennas. It can talk to them when they're way far out, but two low-end antennas talking to each other (rather than to Kerbin) have a much, much smaller range. Even the base level-1 tracking station is literally four hundred times more powerful than an HG-5. Not quite. HG-5 can reach to the Mun, if you stack a few of them. The Mun orbits 12M meters out. The HG-5 has a power of 5M; if you stack four of them on a ship, its power will be 40.75 * 5M = 14.14M. So if you have a satellite with four HG-5's on it in a Kerbin orbit under 1400 km or so, it can talk to a ship on (or in low orbit around) the Mun which also has four HG-5's on it. But HG5-to-HG5 connection going any farther than the Mun (without spamming truly ridiculous numbers of them)? Yeah, forget it. Or you could use this. Nope, it's just the sqrt(a * b). There's no extra term.
  17. What @steve_v said. Also, moving to Kerbal Network, since this is about the forum rather than about KSP itself.
  18. Really? Got an example? An example where the audience viewpoint, in the jet (and not sitting on the ground somewhere watching the jet fly past), actually has a boom sound on the soundtrack? I've seen plenty of action movies involving fighter jets, and whenever they're in the cockpit of the jet (even in the midst of combat on full afterburner), the only sound I recall hearing is a generalized roar of the engine. In fact, your own example calls out the discrepancy-- that the people in the tower (not on the jet) get the boom. And it's not because the jet just happened to accelerate past Mach 1 just as it's whizzing over the runway, but because it was already going that fast and the tower gets the boom when the jet flies past it. I'm trying to think of where I've seen a movie scene where there was an actual sonic boom, and it was called out as such in the movie. The main example I can think of is from The Right Stuff, in the scene early in the movie where Chuck Yeager breaks the sound barrier for the first time. And they make a point that everyone on the ground heard the boom (and got really sad, because nobody back then knew what a sonic boom was, so they all assumed that the noise meant that he must have exploded), whereas Chuck's up there zooming gleefully through the sky, with no idea that everyone on the ground thinks he's dead. I disagree. It would give the user a "what the heck was that noise?" response. Admittedly, my reasons for strenuously not wanting a "boom" sound are due somewhat to "realism" arguments... but even if you want to apply movie physics, I contend that even the movies don't do that. ...because? What "muffled thump" ever showed up at that moment, in any TV or movie? Seems to me it would just add confusion, not immersion. If you really want the user to have some notification of when they pass Mach 1, there are other ways to do that. For example, have a brief electronic "bweeeeeee" coupled by a flash of a little red "MACH 1" indicator somewhere in the HUD. Or something along those lines. I don't particularly need it myself, but I can believe that some users might like that.
  19. Hi, and welcome to the forums! My understanding is that the answer to your question is: technically yes, but in practice, no, and it never will. It's been asked before, and what it boils down to is this: RO forces you to use engines in a way that's fundamentally different from how KSP works with engines normally, and which completely defeats BetterBurnTime. The issue is that RO has minimum throttle for engines, even liquid-fueled ones (i.e. you can't throttle an engine down to zero). RO players cope with that restriction by not staging the engine until it's time for a burn. And that completely defeats BetterBurnTime, because of course it ignores any inactive (i.e. not-staged-yet) engines. An inactive engine doesn't exist, as far as BBT is concerned; it only takes active engines into account. And there are very deep, strong reasons why BetterBurnTime has to be that way. For a detailed explanation about "why is that?", please see here and here, but the TL;DR is "because reasons, and I will never add a feature that changes that restriction, so don't ask." I'm sorry about that-- I wish I could oblige you. But RO is just too odd of a duck for BBT to cope with.
  20. What it does It tweaks the "estimated burn time" display on the navball so that it will be reliable and accurate. It takes into account increasing acceleration as fuel mass is burned. When the ship is in vacuum and on a collision course with the ground, it will automatically show time-to-impact, and the estimated burn time to kill your velocity at ground level. When the ship is in orbit and has an upcoming rendezvous with a target ship, it will automatically show time-to-closest-approach, and the estimated burn time to match velocity to the target. When the ship is on a course to enter or exit atmosphere in the next few minutes, shows time until the transition. For maneuver nodes and closest-approach, it shows a countdown indicator to tell you when to start your burn. What this means for maneuver nodes: You will see a burn time that's accurate to the second. You will never see "N/A" unless your vessel actually can't run at all (e.g. is out of fuel or has no active engines). Shows a warning if the maneuver would require more fuel than you have (see Notes, below) What this means for landing on vacuum worlds: No more messing around with ground-level maneuver nodes to figure out when to start your retro-burn. Download from SpaceDock License: CC-BY-NC-ND 4.0 Source code Why? The "estimated burn time" indicator provided by stock KSP is very rudimentary. It just keeps track of the maximum acceleration observed for the current ship in the current flight session, and then assumes that. This has several drawbacks: You just see "N/A" until the first time you do acceleration in the flight session. It doesn't take into account the fact that your acceleration will get better as you burn fuel It doesn't deal with engines running out of fuel, being deactivated, etc. It happily tells you an estimate even if you don't have the fuel to do the burn. You have to do mental math all the time to split the burn across the maneuver node. This mod addresses all the above problems. Summary below, see the README for full technical details. Notes The "countdown" indicator For maneuver nodes and closest-approach, the mod displays a "countdown" indicator. This is a little row of green dots, immediately below the estimated burn time. This row of dots counts down until it's time to start your burn: when the last dot disappears, start the burn. The display is logarithmic. The last three (biggest, leftmost) dots are in seconds: 3, 2, 1, go. After the first three dots, it's 5 seconds, 10 seconds, 15 seconds, then it doubles for each dot after that. Note: No countdown indicator is currently shown for the "time to impact" indicator; this is because "when should I start?" is more complex, depending on a lot of factors including your descent angle, TWR, etc. This feature may eventually be added, but until then, you're on your own. If you don't like this indicator, you can do any of the following (see mod page on SpaceDock for details): Customize its appearance Make it numeric rather than graphic (e.g. "Start burn in 43s" or "Burn-43s" or however you like) Turn it off completely The "insufficient fuel" warning Normally, the mod displays estimated burn time like this (48 seconds in this example): Est. Burn: 48s If the mod decides that you don't have enough dV to do the specified maneuver, it will display the time like this instead: Est. Burn: (~48s) Note that it won't do this if you have the "infinite fuel" cheat turned on (since then you always have enough dV!) The time-to-impact indicator Under the right circumstances, the mod will display a "time until impact" indicator (instead of "time until maneuver"), along with an estimated burn time which is how long your engine would need to kill your velocity at ground level. All of the following conditions must be met for this indicator to be displayed: The impact tracker isn't disabled via settings (see "Settings", below) The planet/moon whose SoI you're in has no atmosphere. (Someday I may release an update to enable the impact indicator when it's in atmosphere, but not right now. It gets ugly and would significantly complicate the calculations.) You're on a trajectory that intersects the surface. You're falling by at least 2 m/s. The time of impact is no more than 120 seconds away (though you can tweak this with settings, see below). Note that the time-to-impact is based on the assumption that you don't do a retro-burn and just coast to your doom. So if you're figuring out "when do I start my retro-burn to land," you'll generally want to wait a little bit after the point at which time-to-impact equals estimated burn time. The time-to-closest-approach indicator Under the right circumstances, the mod will display a "time until closest approach" indicator (instead of "time until maneuver"), along with an estimated burn time to match velocity with the target. All of the following conditions must be met for this indicator to be displayed: The approach tracker isn't disabled via settings (see "Settings", below) You don't have a maneuver node set The impact tracker (see above) isn't displaying time-to-impact You have a target, which is a vessel (e.g. not a planet) Neither you nor your target is landed You have an upcoming approach within 10 km distance The closest approach is no more than 15 minutes from now You're not within 200 meters of the target and going under 10 m/s, or within 400 meters and going under 1 m/s To slow your craft to a halt when it's close to the target, you should start your burn when the time-until-closest-approach is about half of the estimated burn time shown. The time-to-atmosphere indicator If you're imminently about to enter or exit atmosphere, it shows time remaining. The atmosphere tracker only shows time until transition (there's no burn time or countdown dots). Note that for time-until-exit, it assumes a ballistic trajectory and makes no attempt whatsoever to account for drag. There are config options for this feature in config.xml. If you don't like the default behavior, you can adjust how far ahead of time it displays the warning, or turn the feature off completely if you prefer. Caveats A few things to know about how the mod works. Summary presented here; please see the README for full details. It doesn't know about staging. It assumes that all fuel will be consumed by your current stage. Therefore, the burn time estimate and dV warning indicator may be inaccurate if you're going to be staging in the middle of the burn. (After you stage, though, it will immediately update itself.) It doesn't know about fuel flow. It assumes that all your fuel will be available to all your engines throughout the burn. Therefore, if any of your engines are going to run dry before others during the burn, the time estimate will be optimistic. (After the engines run dry, though, it will immediately update itself.) It ignores electrical supply, so make sure your ion engine has enough power. Time to impact is very simplistic. It looks at the elevation directly under the ship, and at your current vertical speed. It corrects for the acceleration of gravity, but nothing else. This means that if you're flying over rough terrain, the time-to-impact indicator will be irregular (it will suddenly get shorter when you're flying over an ascending slope, or longer when you're flying over a descending slope). If you're hurtling horizontally and about to smack into the side of a mountain range looming up in front of you, the mod has no clue. Be warned. The time-to-impact estimate takes into account your current velocity and the acceleration of gravity, and that's it. It deliberately does not take into account the acceleration of your engines, if you're firing them. It's an estimate of "how long would I take to smash into the ground if I turned off all my engines." So when you're retro-burning to land, the actual time to reach the ground will be longer than the displayed estimate, depending on things such as your TWR, throttle setting, angle of approach, etc. So if you want to time your burn so that you reach zero velocity right when you get to ground level, you'll need to wait a little bit past the point where the estimated time to impact equals the estimated burn time. Also, be aware that this mod will tell you a shorter burn time than stock KSP would, since it takes into account your ship's increasing acceleration as it burns fuel. That's good (more accurate!)... but keep it in mind when judging safety margins (i.e. when to start your engine) when landing. If it tells you that you need 20 seconds to brake to a halt, you really need 20 seconds. Don't say I didn't warn you. Acknowledgments Thanks to @FullMetalMachinist for the excellent suggestion of using a row of dots to show the countdown-to-start-burn. Ask and ye shall receive! Thanks also to @Gen. Jack D. Ripper for usability suggestions on the countdown timer's appearance.
  21. Hello, and welcome to the forums! ...I'm a bit confused by the question. It's not impossible to transmit information that far, merely very difficult-- it's an engineering problem, not some fundamental limitation of the laws of physics. There's also the question of what exactly do you mean by "data". But what really confuses me is the context. What do you mean by transmitting "into a black hole"? Once it goes in, it's not "data" anymore, it's just "energy." There's no "data" in a black hole; you're literally transmitting it into the one place in the universe where there is zero informational content. A black hole has a mass, an angular momentum, and an electric charge; that's basically it. Specify those three numbers and you've fully specified the hole, physically. There's no "data". So it's hard to see the point of such an operation, never mind the engineering difficulties. So... what's the idea behind the thought experiment, here?
  22. Great to see enthusiasm for a modder's excellent work, but let's remember that modders do all this hard work to give us these shiny toys for free, in their spare time, asking nothing in return. They don't owe you anything. Remember that modders are people, too. They have IRL responsibilities such as work, school, family, etc., just like the rest of us, and of course those responsibilities have to take priority over a hobby like modding. If a mod author has been quiet for a while, no doubt it means they're busy with something more important. The mod author will presumably post an update here if and when it suits their convenience to do so. It might be tomorrow. Or next week. Or next year. Or never. Regardless of when it might be, let's remember that they're doing this to give us shiny toys for free and don't owe anybody anything. We're lucky to get anything the author has been kind enough to give us, so it seems a poor return on their generosity to complain that the free cookies haven't been coming as fast as we'd like. All we can do is wait until the author has the time and inclination to update further. And, speaking as a mod author myself, who's friends with a fair number of other mod authors, I can assure you that nothing kills motivation faster than someone complaining about the free stuff you're giving them. So: I know everyone means well, and it's great that you're enthusiastic, but let's not get in the author's way by breathing down his neck and jostling his elbow, shall we? Thank you for your understanding.
  23. Well, derp. For the benefit of other folks in the thread, I shared the logs with KillAshley and he kindly and patiently pointed out that I did not, in fact, have Kopernicus 1.3.0-4 installed, but actually had 1.3.0-1. Ugh. No idea how that happened, I'm usually very meticulous about that sort of thing-- must have had a cached version of a file sitting somewhere or something. Anyway, mea culpa, totally my bad, NH is up and running fine now. Thanks all, and sorry for wasting your time. Looking forward to taking NH for a spin after a long hiatus.
  24. Moving to Add-on Discussions. Though not sure why this announcement is particularly needed here, since anyone who's interested in a mod can just go look at its mod thread. For example, in this case, If a modder wants to enable people to donate, they generally set up a link or something in the OP of their mod thread. I don't know of any such mechanism built into github.
  25. Hello, and welcome to the forums! Sorry to hear about your problem. This seems... very odd to me. By "building a new spacecraft", you mean you were in the vehicle editor in the VAB? If so... a game crash there shouldn't cause any problems with the save file at all. It ought to be physically impossible. My understanding is that KSP doesn't even have the save file open while you're in the VAB; I could imagine being left with a corrupt .craft file (so you can't open up that particular spacecraft), but not the career save itself. What exactly do you mean when you say "broken save file"? For example, ^ when does it say this? While starting up KSP? When trying to go to the "resume saved game" menu? When starting up the save and trying to go to the initial KSC view? When entering a particular building, such as the VAB? When trying to pop up the "load ships" menu? Something else? Also... have you done any quicksaves lately? (either the default F5 one, or a named save via alt+F5)