brdavis

Yesterday, for the 45th anniversary of the Apollo 11 landing, I issued a challenge to my son: land your first career Mun mission on the anniversary of Apollo 11. He did that, and challenged me back: to land my first career Mun mission on the anniversary, and do it within 10 km of the Armstrong Memorial… touchdown was 400 m away. It felt… right.

Short answer: No. "Not even close" is not even close. Long answer: Google "Gravitational binding energy". There are ways (in theory) to disassemble a planet, but that energy is essentially the minimum.

Hmm… Scene: Squad conference room, tech tree development. "So, what about these wheels? Early or late in the tech tree?" "Continuously rotating high-torque electrical motors, with steering, and brakes, with lubricants that can function in a complete vacuum, no worries about degassing, and will remain functional at temperatures between -400° F and ~1500° F, all on a suspension system that can also function under those conditions? Yeah, we can put those right at the head of the tech tree, perfect fit; they'll slot in right before SRBs." Actually I'm not at all sure of that. At least for "real" rockets, that huge amount of fuel and oxidizer actually isn't the main driving cost. It's the engineering to contain it. Based on that, large tanks may still be expensive, but they'll be almost as expensive empty as they will be full. Capsules are not cheap, due to being complex (life support etc.). Engines are not cheap, due to being complex (injector plates, turbo pumps, etc.) as well as using exotic materials (regenerative LH2 cooling of actively ablating expansion nozzles… and we won't even thing about what's needed to get something like a NERVA working, at high-thrust, reliably). I'm not counting on the LV-N being cheap. And it will be a pain to recover as well (heavy to bring back, normally not attached to the crew areas). Then the question becomes, rebalance costs based on driving players towards an assumed set of strategies, or set costs to something realistic and see what happens? Should be interesting.

So… we're questioning the hierarchy of potential contracts, based on something seen in a brief video, on a version that hasn't been released yet, when the contract system is brand new & untested for even simply things like full functionality, not to mention balance. This isn't putting the cart in front of the horse. This is launching the cart to Duna after removing the wheels, then giving the horse a map that's upside down and telling him he needs to find the cart and land it on Tylo.

My first and so far only rescue was when Jeb put the third lunar landing mission down in a crater with too high a transverse velocity. The leading landing strut and side tank tore off and exploded, as did the ascent engine, but he was going just slow enough that the rest survived the crash - he even still had one solar panel (stowed for the landing). The problem was at that point there was no 3-man Munar lander, so the engineers had to invent one and the lift vehicle to get it there, then Doodsel had to perform a precision landing (also not tried before) to get to Jeb. Not only did they rescue him, but recovered science from the crashed mission, and set up an automated surface station. Really was a great feeling, bringing them back from the brink of disaster. Now I'm considering playing for TAC and Deadly Reentry. Things are going to get a little bit more interesting. Well, that or Kerbals are going to get a little bit more expendable, we'll see.

The actual video didn't seem to have as much "fuzziness" to my memory, but the "fishbowl" bending is an expected optical consequence of refraction in that dense (and varying density) air. The prediction is that the land would seem to curve upwards everywhere around you (like you were in a bowl), but there's some question as to if visibility would be good enough to see far enough for the effect to be prominent. It supposedly *is* present in the Venera images, but not at all obvious. As to what Venera would look like now… I'm not sure anybody knows. The surface is pretty calm, winds are low, but it's a very dense atmosphere there. Mechanical scouring isn't out of the question, nor is metal interactions with trace atmosphere constituents, or even metal-metal interactions (different metals at similar temperatures can have some interesting effects). I don't think corrosion is out of the question (I'm not even sure if at those temperatures and pressures some of those metals can be oxidized by CO2, leaving oxidized metals and carbon deposits). Chemistry under those conditions… is bound to be odd. As far as dissing soviet technology… forget it. That they landed anything there, and that it survived as long as it did, was really incredible. They had things like electric motors that wouldn't even fit together to tolerance until they were up above 500° C, and had (but did not deploy) a seismometer where the electronics could function under Venusian surface conditions: http://mentallandscape.com/V_Venera11.htm Yah, the idea of walking on the surface of Venus… is pretty much a non-starter. Aerostats floating in the atmosphere might be rather nice (plenty of solar energy a the same elevation where both pressure and temperature reach about Earth-normal. Not breathable, but that's just better living through chemistry. Not like there's not enough oxygen around). But the surface? Aim at Mars first. Then the moons of Jupiter and Saturn. As well as Mercury. Because (a) all of those are far easier, and ( if you want to actually terraform the surface of Venus, you're going to have to do things like strip-mine most of Mercury for elements like calcium, and import Saturnian moons just for the water. We could put long-term robotic missions there. Geoffery Landis has proposed a system based on what has to be the hottest isotopic power source ever seriously proposed, running a Stirling engine to generate power. I can't find the reference, but there was another multi-stage refrigeration system proposed earlier too… Here's another one to glance at. So… yeah, it's possible to put electronics there, and even have them function. But… a squishy, liquid-water-based low-efficiency system functionally derived to work in an radically different environment? Forget about it… I'll be hanging out in Valles Marinaris, planning a side-trip to Hellas.

Huh. I just realized I have no idea how to actually view the plaques. How do I do that? Looking through my persistence file… Name: First Landing "Here Kerbalkind first set foot upon the Mun... and it was sort of soft and squishy. But dry." Name: Conyon Scientific Station (OK, so Bill can't spell, but he can land!) "2nd landing, first deployed AMSEP (Alice Munar Surface Experiment Package). Magnificent Desolation." Name: Desolation Point "Site of Jeb's crash-landing of Alicia 4. If I'm lucky, it will also be the site of a rescue." Name: Midland Crater AMSEP "A rather more elaborate AMSEP" Name: Duna Landing "Here Kerbalkind first set foot upon the... hey, that's a pretty rock over there... I wonder what's over that hill…"

Imagine this place: Astronomers find "Mega-Earth" Note that while it almost certainly has *some* atmosphere, probably a pretty significant one at that (Venusian at least?), it's certain *not* a gas giant with a density like that. Talk about a challenge…

Thank you all - some of these I already knew, some were new. I've manually changed the conic type and zoomed in on the SOI to see what the result was, but the problem is trying to keep that up and visible and still have access to all the handles on the node itself (which may be quite far away, or as another mentioned "seen through the Sun"). I ended up adding PreciseNode and Kerbal Alarm Clock, both of which *greatly* decrease the frustration. MechJeb would probably be good… but like some others, it's not my style of play. AlexMoon's calculator is great as well (combining that with PreciseNode let me set up a Jool intercept from 100 km Kerbin orbit the very first time… impressive use of both tools!).

I'm a physicist, so I've got a reasonable grasp on how to do an interplanetary transfer; and the maneuver nodes make setting things up pretty easy (yes, I'd like ejection angle readouts too; but I'll deal with it ). But one thing that bugs me is trying to see the effects of adjusting a maneuver node where the proposed trajectory intersects a distant SOI. As an example, I was 4 days out from intersection Kerbin's SOI on a Duna return trajectory and about all that could be seen was that things were changing… I had to fine-tune my entry trajectory by tweaking the maneuver node while mousing back over the Kerbin periapsis marker to figure out if at was getting smaller or larger… and then when I found the minimum in one axis (say, pro/retrograde) I'd have to repeat the searching in a different axis (up/down or radial). It's like a nearly blind optimization search of a five-dimensional phase space (X/Y/Z time of maneuver and delta-v magnitude). Suggestions? Tips? Tricks? Up until now I've often used the inefficient method of multiple maneuvers (boost to orbit ==> eject to edge of SOI ==> adjust inclination ==> transfer to Hohmann transfer orbit, etc.). I know that's inefficient, but the frustration of not being able to "see" what effect I have in the (often distant in both time and space) SOI is really a difficulty. I don't use MechJeb or Engineer (although the Edu mod does give you some of Kerbal Engineer functionality, and I'm testing that), so I'm looking for the best way (not the perfect way) to do this with a mostly stock install. Oh yeah, RCS makes interplanetary orbital refinements much more enjoyable….

I had serious thoughts of photoshopping little glowing lines on it, but the coincidence of the floating boulder coupled with the view of Ike… no, KSP reality was better.

Playing Career in 0.23.5, had number of firsts. First Duna landing (& return) with leg room (at least two seats for every Kerbal for those long, dull, interplanetary voyages; even included some extra snacks by attaching KAS containers to the transfer stage), and simultaneously first robotic one-way Eeloo mission (with Kethan scanner). Bill and Bob learned a lot, including what happens during Duna ascent when one side runs out of fuel first, how to get to low Duna orbit on RCS, and docking, not to mention the first use of AlexMoon's calculator (I've been doing them all by hand… this has probably switched me). Two simultaneous missions is… interesting. Bill & Bob landed near the mouth of a canyon system, with Ike just hovering over the horizon, and set up a nice DSEP (Duna Surface Experiment Package) as well as took a couple of multi-kilometer hikes. Found some very odd, interesting boulders too… Landing site with Ike over the horizon, and the KAS-constructed DSEP in the right foreground. They made sure the drop tanks weren't going to pulverize it on ascent too. Bob encounters a rather interesting rock (First time linking images in, let's see if that works)

Yes. It's been talked about and hinted a couple of times. No.

I have a college-level lab I wrote based on a small KSP craft in orbit; it was more basic than what people are talking about, because Newtonian physics needs to be the starting point, so I used it to study impulse, acceleration, and conservation of energy if I recall. I really need to post it, but I haven't yet. Do people want to see it? As far as the Edu version… it's nice. I've been testing it, and they are incorporating a lot of the things teachers can use in simple forms. Once I realized I could text-edit my way into orbit with a fueled ship designing lessons got a *lot* easier. Launching into orbit… is not, perhaps surprisingly, where I would start for a lesson. There's too much going on when you are trying to focus on the physics.

Grin. Yes. New feature in 0.23 (IMS). Hover the mouse over the "ring" of an expanded node, and when just the ring highlights, click and drag it along the orbit. Yes, it makes life much easier

There are some other potentially interesting aspects to the science lab with contracts. What if a contract specifies you need to return a certain amount of science from, say, Duna, in a narrow time window? A window too small to take a Hohmann transfer out, and one back, but one big enough to get out there and "process up" some data from landers to transmit back? Think the the 'space race' - getting there was only a part of the challenge, getting there *before someone else* was just as critical. I agree it might need more… and personally I *really* want an IVA for it, just because it's the largest stock habitable module around (are the round things windows? I want to look out of them!!). But I've used it at Minmus and really enjoyed it - it not only allowed me to feel like I was maximizing science (without spamming landers everywhere), but it just felt… *right*.

And lots of us that are content on-forums spend more time reading than talking about our exploits. I don't build big… but I try to build close to the margin. Nothing makes me happier than completing a mission to, say, Duna… except competing a mission to Duna and having next to no propellent margin

I was wondering how quickly this would pop up here - it was XKCD that first informed me of KSP… and now I'm using it to teach in my university physics labs. So… yeah, I have to agree with him. And I say that as a physicist

Thank you for the links! Now, I've just got to figure them out

Is there a tutorial on… writing tutorials? I know there are new ones coming out in 0.24, but I'm thinking it would be very nice to write some of my own, for teaching purposes… and while I'm sure this has been done, I've yet to find hints and tips. Can anybody direct me? Yeah, I'm just going to dig into the files, but I suspect I'm going to be reinventing the wheel here so I thought I'd ask.

High points are made to be exceeded… But I remember (dimly) my first orbit. I remember my first (Mun) landing and return (heck, even the unmanned probe that preceded it was exciting). And then came… My first docking on-orbit! I think I literally yelped when they snapped together and the POV shifted. I had put up an Agena analog, and then went through getting a small craft into orbit, figured out how to match inclination, then worked (oh lord, how I worked) on figuring out how to close the distance. But when I docked, wow, that was incredible. That one simple little lousy "station" is still my Facebook cover photo, although I've done far more since. But going beyond that, it would have to be an Apollo-style Duna lander and interplanetary transfer stage with drop tanks. Minimal, as I had no experience with heavy lift vehicles; you had to reconfigure the hardware half a dozen times during the mission, and I sweated every bit of it. I'd done the dV calculations by hand in detail, as well as the launch windows, orbital speeds, everything. Designed the mission down to the last 100th of a ton, with very little dV margin… and it all worked, exactly as planned, the very first time. Apollo 11 touching down could not have been more exciting to me at that moment.

I actually use (when teaching) pericentron and apocentron, although periapse and apoapse are just as well… but i never understood why anyone would use perigee (and perihelion, and pericynthion, and perijove, etc., etc…)

I decided I wanted to make a heavy lift vehicle that would put an orange tank into LKO. So… I worked out the math, on paper. I wanted to do a light-weight single-Kerbal mission to Duna… so, I worked out the math, every potential step of the way. Currently I'm aiming at going back to Duna with a two-Kerbal mission, including a Hitchhiker just so they have more room for the long trip, and they'll visit Ike as well… and working out all the math on paper. Including transfer windows, etc. Why not use Engineer or MechJeb? Nothing more than personal preference. If I choose to run a marathon, it's not because I have a requirement to arrive at a place 26.2 miles away… the fun isn't in the destination, but the path you choose to take to the destination.

And that's really one of the beauties of this game - I can do it any way I please . Personally I sort of agree with you - I'll play the ARM, but I might end up doing it with more stock than special parts. It's an Add-on, not part of the "stock" game in some sense, right?

I'm not positive… seriously, I've only had this since like 0.22, so newbie here… but I thought the idea of a gravity turn is to let gravity do all the turning: go straight up until you start the gravity turn (by nudging your nose maybe 5° eastward), and then let gravity turn the heading as it needs to. In one sense that requires very little control (Newton is in the driver's seat), but it does require figuring out when to start it. Try experimenting. As far as not leaving space junk… use the core stage to *almost* due to circularization burn, then dump it, and supply the last tiny bit using the on-orbit capsule. Or, hey, with tweakables, remove fuel from the stages