KerikBalm

Well, my point is that while there is water there, you will need to process a lot of atmosphere to get a small amount of it. I am not saying that it is inaccessible, just that there is not that much per unit volume

*edit* oops, forgot what the thread title was: its not science and spaceflight facts, its just space facts Anyway, back to the main topic: Earth's life used to be mainly purple Our cold blooded semi-aquatic Crocodiles come from warm blooded fast terrestrial ancestors with a 4 chamber heart. There was probably pre- cellular life without DNA. We can't really construct any good phylogenetic trees for most of the viruses, and we don't know how they came about likely multiple independent events- but there is a good chance that some come from lineages that predate cellular life

The clouds would be quite safe, from radiation anyway

https://www.nature.com/articles/s41598-018-38180-4 I can't find anything about long term effects of large amounts of hydrogen gas, its clearly not noxic in small quantities... but I missed one really obvious thing.... and a large reason why you'd never be living in a dense hydrogen atmosphere for long periods of time: https://www.nap.edu/read/12032/chapter/9#152 Mixing hydrogen and oxygen in your habitat is a bad idea, even at just 4% oxygen (and 5 Bar!). So that leaves Helium... which means that you will need a very big temperature differential to float. Saturn is a similar situation. Yea, you're not going outside while floating in gas gianst, I guess.

I should also point out that if your goal is to blow the rock apart, a pulse laser could do what you want. While a continuous laser may cut by melting through, and a rapidly pulsed laser can "drill" through, a massive petawatt pulse laser will essentially make the rock explode at the surface, and will act very much like a chemical explosive detonating right on the surface. If you drill with a few small pulses, then set off a big pulse into the hole, its very much as if you just drilled a hole and detonated an explosive. As far as energy efficiency, a free electron laser might get 50%. A railgun... that depends on the material property. If the round goes clean through a rubble pile, with the shockwave scattering the rubble, you basically need to compare the KE of the railgun slug, to the KE imparted to the rubble. If its a more solid metal, and you fracture it, then well done. Anyway, as far as weaponized space lasers, I think people often underestimate the potential effects on the target. Vaporizing a significant amount of material right on the surface is literally like detonating an explosive on the surface... granted, against a tank, high explosive shells are ineffective, and you're not going to get the effect of a shaped charge /explosively formed penetrator - but it would still shred lightly built spacecraft, and the effect would primarily be kinetic, not thermal

Yes, you can't have acid without water, this gives the details that I was referring to: https://www.liebertpub.com/doi/full/10.1089/ast.2020.2244 Yea, I meant to end my post with: "dat gravity tho..." but I forgot by the time I was done with the gas discussion :p

and if you did, just do that step, without all these other intermediates!

That sufuric acid has very very very low water content. Venus is severely water deficient (see the thread about possible life/phosphine in the Venusian clouds), I doubt it. As for the gas giants, well, if you had a super-duper fusion reactor, you could fuse the hydrogen and helium into heavier elements. A CNO fusion cycle perhaps, you can make a lot of structures with various carbon polymers... but even fusing to Iron, much less heavier elements, assumes a very very powerful fusion reactor. Gas giants are most useful as hydrogen and helium sources, best taken by an orbiting spacecraft skimming hydrogen/helium off the top. Indeed, but that would be a similar issue with Venus. As long as its not too toxic, then a facemask with a decent seal is all you'd need. As for Jupiter,You'd also have to worry about decompression sickness if your habitat ascends, or you ever want to leave jupiter (or your spacecraft needs to be pressurized to 5 bar, requiring more dry mass, making getting away from jupiter even harder). I'm pretty sure hydrogen gas is not toxic, like N2, Helium certainly isn't. I don't know about the other traces, I think Ammonia is in there too though, which isn't great... You'd have to adjust the gas composition that you breathe, but it shouldn't be too different from scuba diving. At 40 meters below the ocean's surface, the pressure is already roughly 5 bar. https://space.stackexchange.com/questions/10895/maximum-survivable-atmospheric-pressure#:~:text=The maximum pressure for long,therefore is about 2.5 bar. Plenty of Helium available on Jupiter... so yea, a hab at 5 Bar, with a breathing gas composition of mainly helium with about 4% O2 would let you go outside... but.... Buoyancy of the hab would be a big problem though... trying to float in an atmosphere of mainly hydrogen and 10% helium? You'd need to float not by having a lower average molecular weight gas, but by having a warmer gas. If you've got a fusion reactor, there's plenty of fuel for it, and you can heat it indefnitely. The question then is how much would you need to heat the habitat's gas envelope? would you have a seperate heated envelope for buoyancy, such that the hab is at an altitude where you can go outside comfortably, or do you heat the atmosphere and internal volume of the habitat to produce buoyancy... what sort of temperature differential would you need, could you keep the hab at a relatively comfortable 27C (300K), and be able to float in a region of the atmosphere that still alows you to go outside and not freeze/have the problems of being on Titan? The denser the atmosphere, the more that cold temperature is going to freeze you faster. I guess I'd put the limit for an acceptable outside temperature as a first guess at -20 C. Bundle up... So, next question, how much buoyancy would you get from each m3 of a 96.5% H2, 3.5% O2 atmosphere at 300K and 5 Bar, vs a 90% H2, 10% He atmosphere at 253K and 5 bar? I could do the math, but don't want to right now :p Oh geez, you must mention such a spacecraft in like 75% of your posts in this subforum What? that sentence seems incomprehensible to me. Could you rephrase it? What? that sentence seems incomprehensible to me. Could you rephrase it? Yes, I agree with that analogy I don't think that's a good analogy, because with orbits the spacecraft doing the tighter circle is also the one moving faster. The spacecraft doing the wide circle (high SMA, low eccentricity orbit) is moving slower. You temporarily speed up (+ delta V) to go to a higher orbit, but end up going slower. A one time increase in speed raises apoapsis (raises SMA, raiss eccentricity), resulting in your craft sometimes moving faster than before (at Pe) and sometimes moving slower (at Ap), and always taking longer to complete an orbit (because SMA is higher). I don't think that translates well into an analogy of a plane turning.

No, it wasn't. No. Haven't you realized yet that you're not going to get around this, that the forces will always cancel out. Putting in more steps /intermediates doesn't change anything. Now you've just added air as an intermediate, but it changes nothing. Equal and opposite forces are exerted. A=B, B=C, C=D, A=B=C=D, thus A=D. Its really very very very simple math, the transitive property. Sticking steps B and C in between A and D change nothing. The force is equal and opposite... do you have any reason to think any given step does not have an equal an opposite reaction?

Under this system, the center of mass of your ship dors not move, but you may displace part of your ship - like the nose going forward as the plate goes back. But then the nose goes back as you retract the plate. All cycling this does is to shake the ship, and never move it anywhere. Center of mass never moves, the ship just shakes around it.

I was wondering if any of the gas giants would be suitable, knowing the atmosphere gets hot as you go deeper... nope: Also note that Venus is quite hot at 1 Bar. At the top of Mt Everest, air pressure is 0.3 Bar, and that is quite survivable... sure going up there without O2 will lead to low level brain damage... but... thats the lack of oxygen. Venus at 0.3 Bar is not too warm at all, and inside the habitat, you can pump up the percentage of O2, so that thehab is at ambient pressure, but the residents don't suffer hypoxia.

I would have the stars be visible, but not the planets. Then with some telescopes, you can figure out how many planets, and their bulk properties (radius, mass, atmosphere), but you need to visit the system to see surface details

oh god.... looks like I'll be sitting out of KSP2 for a while until all the DLC is out in a cheap bundle... already waiting for 2022, so, yea, whats another year or three.

Well, I already mentioned that PSM refueling will need more infrastructure.... although the resources (hydrogen) to manufacture it would not be rare at all. I also would not assume that the ISRU drills and refinery from KSP1 that work for KSP1's chemical rockets will make a return in KSP2, given the colony mechanic. So that leaves us with just the idea that you need higher level equipment to make PSM fuel, fine I see no reason why PSM engines cannot be made in similar small variants. Anyway, PSM should not be the main focus of this dicusion, but rather engines making use of beamed power, that should give similar to better performance, but be more complex to use ... I think the added complexity would make for more interesting gameplay, but it seems some people do not agree.

Well, due to the lack of details, we are engaging in speculation. I could also speculate that it just means that you need to land more material to start using PSM channeled by the colony for supply routes and new ships... Well, I mentioned fusion AND Fission. NTRs are certainly compact and will be included. It will be interesting if they require both propellant and occasional refueling with fissile material. Well, its a big fear of mine. The PSM engine seems like its just a straight up upgrade to chemical rockets, and I don't see how they can introduce any new challenge that the PSM engine solves, that couldn't be solved with chemical if you don't just tweak the gravity and celestial body radius numbers... It certanly seems to me like it will lead to the RPG example, whereas other techs can have mechanics that make unique challenges (balancing power generation and heat for the large interplanetary and interstellar drives, dealing with radiation, specifics of using the atmosphere and flight profiles in jet and air augmented rocket designs, etc). The only possible limitation I can see is how much infrastructure is needed to make the fuel, and that seems like it should be able to be solved (speculating) by just bringing more stuff when you first set up the colony. All these other techs have some quirk that separates them from just a drop in replacement for chemical rockets, and beamed power would follow that trend with its own unique gameplay restrictions When that can already be abstracted by setting up supply routes, I don't see how a drop in replacement for chemical rockets that just gives you better performance changes anything. It just makes getting to orbit (whatever the specifics of that challenge for a given body) easier. The power beaming aparatus would be infrastructure just like the PSM channeling infrastructure, so that part is more or less equivalent. It would create unique gameplay because (depending on your infrastructure), you'd have the improved performance only at specific parts of your flight. Look at various designs on atomic rockets. To go from surface/orbit where you have the power plant to a distant destination requires some sort of hybrid ship with a propulsion system that works at the destination (as seen in the interstellar ships in the fictional "Pandora universe"), whereas PSM drives just work anywhere, no restrictions. Depending on the location of your power station, its capabilities, and your receivers capabilities you'd experience variable power, which would be a unique gameplay challenge to deal with. It would also lend to more gameplay around orbital mechanics, perhaps PE kicking just the right amount so that your ejection burn is done when the craft is in optimal receiving position relative to the power station. You could even have designs that can also use high levels of solar irradiance, as some designs (similar to "solar steamers") could equally use sunlight or incoming laser light. Use a laser to depart kerbin, and plain old sunlight to do an orbital insertion (or at least orbital maneuvers if the power is still too low for a full capture burn) at Moho... or something like that Since a lot of the KSP2 gameplay will apparently balance power and heat, that can also apply to this drive as well. Operating at full transmission power requires balance not just at the transmitter, but also at the receiver, which may overheat if not properly designs and utilized, etc... It seems to me like it could provide many unique gameplay challenges. Some other tech just seems like a drop-in upgrade from chemical... which seems boring from a gameplay perspective, and when its not even based on reality, its not even a matter of compromising somewhere between gameplay and realism.

Two points: 1) I somewhat expect that chemical will still have some role in KSP2 despite the higher tech, when first establishing/bootstrapping a colony. Making hydrolox fuel would be relatively easy (electrolysis of water/ice), wherase one can expect that channeling purple space magic will require construction of elaborate temples for the rituals. Similarly, producing advanced fission and fusion drives will take more manufacturing capability than a chemical rocket - perhaps even giving pressure fed chemical (perhaps even monoprop) rockets a role, as they could be the first thing a growing colony can manufacture. 2) Just making a higher tech better than a lower tech in every way means that the new challenges are basically just reskins of the old challenges... I htink its poor game design, and reminscent of grindy RPGs from the '90s and early 2000s when higher level foes were basically reskins of earlier foes, with stats increased proportionately to match the improved stats of your character. For sure, there are many ways to implement it, but I don't see it being much more of a logistics hassle than using probes and dealing with probe control points and commnet limitations - with the change here that lower "signal strength" leads to less engine power, and power stations would act like probe control points that aren't multihop capable. Also, such a system could serve a variety of purposes. You could use beamed power for surface to orbit shuttles, as well as for the outgoing impulse of an interstellar ship, like the hypothetical breakthrough starshot or the fictional venture star ( https://james-camerons-avatar.fandom.com/wiki/Interstellar_Vehicle_Venture_Star ) which uses beamed power/a photon sail to leave earth, and an antimatter engine to decelerate at the destination. Beamed power wouldn't be a one trick pony to replace purple space magic. Nor would it be a true replacement. With beamed power you wouldn't need the elaborate temples on the surface to channel PSM, you could use more basic ISRU facilities for chemical propellent/hydrogen production as long as you have a power beaming ship/station in orbit (which could use solar panels and capacitors). In contrast a PSM powered shuttle would need the colony to be able to produce PSM for each trip, so when establishing a colony, it will either have to get by without PSM shuttles while it bootstraps, or you need to send enough equipment (and store enough channeled PSM for the shuttles to bring stuff down) to begin immediate channeling of PSM.

What? the change in velocity is 1948 what? meters per second? or 0.017 m/s (17 mm/s). Funny, I used a flea for propulsion on my craft, and it had a dV of neither 1948 m/s nor 0.017 m/s. Perchance you have made an error in your calculations?

From my perspective, it would be great gameplay, and really fit into the KSP2 theme. A lot of KSP2 seems to be about using future tech, and setting up infrastructure. Beamed power checks both of those boxes. It would add a commnet-like gameplay mechanic as an alternative to using nuclear engines (which have a radiation mechanic). In both cases there is a gameplay tradeoff for the performance gains over chemical propulsion. Or.... you know... just throw in purple magic and have something that requires no infrastructure to operate, has no radiation concerns, and gets you superior performance to chemical and solid core NTR... [sarcasm]yea, now that I type that, never mind, that last one sounds like better gameplay than beamed power[/sarcasm]

Please tell me how much dV is equivalent to 1000 watts... I want to know

Imo, beamed power to get the performance of mmH is far less cheaty then mmH, as it requires the reactor somewhere nearby(not an insignificant undertaking), line of sight, timing your flights r establishing something like comm-net, adding a gimballing receiver to your craft, etc... Or you can just have mmH that magically stores all the energy that you need. Plus, a fleet of motherships with power beaming equipment could easily be turned into warships :p which is a cool thought.

http://www.projectrho.com/public_html/rocket/surfaceorbit.php#laserlaunch https://en.m.wikipedia.org/wiki/Laser_propulsion I'm wondering if KSP2's engine can support some kind of beamed power propulsion, and if so, could it be included in the game? Once you have a colony all set up, you could build a large laser or similar and use it to power a variety of drives that could equal or exceed various types of fission propulsion, without the radiation issue... Likewise, an orbiting mother ship could do beamed power for a lander. Just a thought, it would be nice to see.

I don't know what is going on with your area, but the vast majority of scientific papers do so. For reference, a paper we just submitted with 315 positive cases from our testing center, then mean Ct value was 22.5. Also note that Ct values cannot be directly compared across different tests and sample preparation methods. Furthermore, if you get tested early in the incubation period (as part of contact tracing), the PCR result may be negative (that is, not detected even after 40 cycles). There are two sides to a peak, and Ct<35 doesn't just detect "old" infections - granted that the slope at the start of the infection is steeper than at the end.

No, asymptomatic spread is definitely a concern. Children and youth still shed similar amounts of virus, and at least one stdy found asymptomatic transmission accounts for 44% of new cases: He X, Lau EHY, Wu P, Deng X, Wang J, Hao X, et al. Temporal dynamics in viral shedding and transmissibility of COVID-19. Nature Medicine. mai 2020;26(5):672‑5.

I disagree, if you want to launch 2 missions simultaneously, then its needed. Some of us care about how much time passes in game and want to do missions in parallel. Not focused or not, KSP1 doesn't allow acceleration on rails. The big improvement is acceleration on rails, and when its on rails, it shouldn't really matter if it is focused or not.

so... 86 seconds on the starship = 100 seconds back at kerbin, I don't consider that huge ... granted, in another thread I mentioned I'd set the cutoff for acceptably ignoring time dialation at a 10% difference which is 0.4c not 0.5c. Atomic rockets on the other hand uses 1%, which would be 0.14c http://www.projectrho.com/public_html/rocket/slowerlight.php http://www.projectrho.com/public_html/rocket/slowerlight.php At .99c though, then its going to make huge differences in terms of time elapsed for the crew, changing the level of life support they'd need by an order of magnitude