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    I don't build rockets, I develop space

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  1. Nice job, I always make a point of doing a close fly-by of that peak when I land a space-plane, it is quite impressive. At the risk of making you do a "why didn't I think of that" faceplant... I would just have slapped a few downward pointing RCS thrusters on it, or is that against the rules?
  2. Today, day 412 of year 5 marks the first day that I have 4 star crew available in the Kerbin system. I've had 4 star crew for quite a while, but they all earned their 4th while 'on assignment' and haven't been back yet since. It's also the day my first interplanetary tourist returned safely to Kerbin surface. I've brought plenty back from Mun, Minmus and Kerbol orbit but this one came from Eve/Gilly. Unfortunately I can't close the contract yet and get the reputation reward because one of her travel partners wants to go to Duna/Ike too, but the money has been paid. I accepted a juicy new contract: I figure if I build something that can do Kerbin-Moho, and can get down to and back up from Duna surface without parachutes, it should be able to do the rest too. I have refueling stations at every stop. This is what I came up with, simple enough, I did a test run on Duna and had no trouble putting it down and back up to 200km orbit with fuel to spare. The separate tank is to carry extra fuel for the hard transfer burns, it will stay at the local refueling station while the probe does its landing: My Ultimate Gilly 6 Voyage probe (fly-by of Mun, Minmus, Duna, Ike, Gilly and finally crash on Kerbin) is on its last leg, around 1.5 years left to go to Dres after which I can set it on its crash course. It's nice to have another long term challenge to replace it. Another flag-planting team building activity for new recruits. I'm not much of an easter egg hunter but lately I've been sending these trips to mysteries on the Mun and Minmus, just to clear them off the map They came across one of the new ones, too bad my science tree is already completed:
  3. They are developing "radioactive batteries" based on Selenium for pace-makers, essentially a micro-RTG suitable for wetware. Size and thickness of a penny and producing 16 nW at 0.9 V. My SI Standards book didn't list a conversion ratio for pennies to human body, but according to some googling a penny is about 0.35mL. Assuming the battery doesn't have a bass-relief and scientists tend to round favourable when talking to journalists, let's say 40 nW out of a mL, or 40 uW out of a liter, or around 3-4 mW out of an acceptable proportioned human body. That doesn't bode well... And that's assuming the entire body is made up out of these batteries. Let's forget the "must not sterilize every human in a 10 km radius" requirement for a moment... "The spacecraft [Cassini] also carried 82 strategically placed radioisotope heater units (RHUs), which provided focused warmth in the form of one watt of thermal power each using a pencil eraser-sized pellet of plutonium dioxide." Hmm, no mention in my SI units book about pencil erasers either, but it sure sounds more promising. I'd say a pencil eraser is around the same volume as a penny, since we already established there are around 3000 of those in a liter, at a 5% conversion to electrical that's 150W for a 'heart' of 1 liter. Not bad. Of course then you need the lead shielding, and a way to get rid of almost 3kW of waste heat. And I'm not sure how far you could push that stuff before you reach critical mass... Of course this is an RTG, not a 'nuclear reactor', however I'm pretty sure reactors don't come in a size anywhere near small enough to fit into a human body volume. The mentioned 150W should be enough though, in theory, after all biology got it done I would add to that that a LOT of our energy goes to keeping warm (which you won't need to worry about with 2.85 kW of waste heat) and to our digestive system which we could also scrap. So a beer can sized plutonium dioxide pellet might very well be enough just to drive the CPU, sensor package and actuators. I really need to get a new edition of this SI Standards book, no beer can volume in there either... I think all in all the problem is not so much to fit enough nuclear material to generate the needed energy, but handling all the side effects like heat and radiation. A rechargeable chemical energy source might be more efficient in the end (again, it's what biology came up with ) but of course makes the android vulnerable to simply running out of juice - just like its human templates.
  4. Guilty :s I loved how every shot of the moon later on in the show would have that 'defacement' but I always wondered how he was going to fit his whole name on there writing that large...
  5. Welcome (back) @Andrew Jolly, yes hinges! As it happens I just gave them a little workout, see below So my idea to extend my Gilly mining rig arrived, here some pictures of the arrival and assembly. I've spoilered them because there's quite a lot.
  6. Love the parasols, I will steal that idea at some point
  7. 8 new recruits on a team building trip. My Minmus lander only carries 7 but my station had some space in the fuel tanks, so I sent my tanker along with it for an extra 2 seats: In the background (ltr) the "Rock o' Max", a fuel depot/highrise living sponsored by Rockomax Corp, the Jeb's Junkyard Bike Garage/Workshop, and the main Jeb's Junkyard spire flanked by its rovers. In the foreground my mobile refinery, the tanker, Ferford Kerbin planting a flag, and the 7 seat lander. I've also done the transfer burn for my Pol convoy, all night side burns unfortunately. The tanker with the rig attached, 1 Rhino and 6 Wolfhounds: 5 Vectors on the station segments: And a single Rhino for an orbital tug with a crew transporter/lander on top: About a year to their plane correction burn, then 2 more until arrival.
  8. Dang, I seem to have picked at an open nerve, sorry about that I'm going to assume that none of you have really thought through this idea of retrieving Hubble because frankly, the alternative explanations are a lot more unpleasant. Let me spell it out for you: this is a mission that would require extensive, days long, possibly weeks long EVA activities by multiple astronauts handling an 11 ton metal monolith in 0g, performing welding and cutting operations, and probably handling dangerous and pressurized materials in the process. I'm not aware of any nuclear material on Hubble but even without that there is plenty of stuff that can go woosh, crack or boom. It's not like Starship can fly up to it, open its 'beak' and just scoop it up and fly back down. No matter how cheap you can make your Starship launch costs, the costs for this operation would be expressed in the potential loss of human lives, not millions of dollars. And before you say "what about robot arms", nope, sorry, not a chance. Even finishing the SCM, which was the safest and easiest solution they could come up with and is already well prepared and for all intents and purposes half finished would require a crewed mission to complete. Being an astronaut isn't a safe occupation even at the best of times. The days of dare-devil test pilots is long past, this isn't George Clooney cowboying around with a jet-pack, those people are scientists and top engineers who do the work for the advancement of science and knowledge, and you're proposing we ask them to risk their lives in the name of commerce and sentiment. It's like you're standing next to the fireman who just saved your entire family from your burning house and even remembered to bring the kitten and dog, and you're insisting they run back into the inferno to retrieve your high school chess trophy because it means so much to you. I find it immoral and indecent to even entertain the notion of asking that. This is the last post I'm going to make about this because I think my opinion is clear, and you know what they say about arguing on the internets. All I can ask is that you take a moment to really think through what you're proposing here, what the potential rewards would be, and offset that against the potential costs. If you've made that balance and still think it's a good idea, we are clearly not cut from the same cloth and we'll just have to agree to disagree.
  9. I suspected someone would bring that up at some point, but that comparison just really doesn't fly. The Wright Flyer was built to land back on earth, and it did. The Shuttle was built to land back on earth, and it did. Likewise for the Spirit. What people are proposing is to heave up the Titanic, not to put a big plane on a truck and drive it a few hundred km. It's an entirely different order of magnitude in terms of effort and resources. The thing did nothing. There was a huge team of thousands of people who did a lot of work, and we have the results of that work right here at our fingertips, without the need for an orbital fishing mission - because that's how it was designed. The thing only has meaning if people don't recognize that work, and giving the thing meaning with proposals like this reduces the actual meaning of all the work and effort that went into it. Given the choice I sincerely doubt anyone who actually did work on Hubble would choose bringing it back over putting up a Hubble v2.0. And yes, that IS what the choice would be, it's not a "we can do both" issue, because... I think you underestimate the costs. But even if not, if some space nerdy billionaire (I'm not dropping any names) says "I want to go get Hubble back to earth", I'm not going to tell anyone how to spend their fortune. But then what? They'd likely want to keep it, or recoup the costs by selling it back to the original owners. So, ignoring the legals issues of that which I have no doubt would be horribly thorny, it's either going to end up in some rich guy's basement which defeats the purpose of serving as some perceived symbol for the people, or (if done 'right') being paid for out of NASA (and perhaps ESA's) pockets, reducing their ability to support new science missions.
  10. A Clarke fan as well as a Stan Lee fan I see, excellent But if the airship-like organisms store most of what is already considered a precious and scarce gas, surely there wouldn't be enough free oxygen left to create an atmosphere breathable to humans? Or do you suggest bringing a big box of needles and popping them all?
  11. I think we can safely banish the idea of post-scarcity to the realm of myth by now. If crypto/NFTs have shown us anything it's that humans will happily create artificial scarcity if it does not naturally exist And it didn't start there of course, from baseball cards to beany babies, humans seem to crave to be 'special' by owning things that others cannot own. When it comes to aliens it's all speculation of course, anything is possible, but a human economy as portrayed in Star Trek and the likes seems implausible given the human condition. One might even argue that scarcity is what creates the entire concept of an economy, and thus if there was an alien race that lacked or overcame the human desire for it and also overcame natural scarcity, it might not even have anything that we would recognize as a 'economy' by any definition of the word.
  12. I never really get this obsession with specific inanimate objects, I don't seem to share it to the extent that others do. Hubble is a tool, it's no more important than any one of the many hammers used to build the launch tower it was released from. And yes I fully realize someone is going to come along to explain how vitally important it is we save all the hammers that were used for building said launch tower. I have no problem with calling any plans to retrieve Hubble "utter lunacy" and I will stand by that, and I sincerely hope nobody who is ever in a position to make decisions about this thinks any differently. I would be hard pressed to come up with a more wasteful idea w.r.t. space exploration funds and resources even if I tried really hard. Foregoing clean room conditions, mirror/lens precision requirements and space hardening you could literally build a perfectly adequate educational mock-up of Hubble for every single space museum on earth, and have money to spare to send up your next telescope. The design process of Hubble was important, so stick those design schematics and plans in every museum. The data it generated is important, so stick those pretty deep field pictures in every museum. The telescope itself is not important, it is a tool as long as it works, and garbage when it does not anymore. Do we really want to ferry garbage back to earth at double the cost of a mission to send up a new tool? Incidentally, it's no coincidence that both the design schematics and processes as well as the scientific data could easily be copied and shared all over the world, but the telescope itself cannot. In science, if it can't be shared, it's worth precisely nothing. It's an interesting example to bring up, because the major source of inspiration out of the Apollo missions that still lives on is the Earthrise picture. Not the capsule it was taken from, not the camera it was taken with (although I'm sure that is stuck in a single specific museum somewhere too and gets many oohs and ahhs from the few people why paid to see it), but the picture itself. Which hangs in every space museum on earth.
  13. A breathable atmosphere for humans (obviously) requires around 20% of oxygen. Oxygen is highly reactive and unlikely to exist in those concentrations without some process that constantly replenishes it. If new Oxygen wasn't constantly being generated on Earth it would all just be used up in fires and less violent forms of oxidation and end up as some carbon-oxygen compound or water or various metallic oxides. All in all that means it's unlikely we will ever find any kind of planet - rocky or gaseous - that has breathable air unless that planet already contains oxygen-producing life forms. Before life, Earth had very little free Oxygen, and the first appearance of oxygen producing life very nearly killed everything on the planet, including the life that produced it, due to the extreme chemical changes in the atmosphere and oceans that it caused. See the "Great Oxidation Event", it's a very interesting episode in Earth's past. Of course we have no examples of life existing on gas giants, so if that would even be possible is anyone's guess, but it's safe to say that if we ever did find enough oxygen in a gas giant's atmosphere, there'd be something there that might not want to share it with us
  14. I often find them to be the best solution for stuff on Kerbol orbits. I have a probe design I use for setting up relay and asteroid scouting constellations at various orbits around Kerbol that run on a single engine and large Xenon tank. The low thrust is generally not a problem when you're in orbit around Kerbol. I also use 19 of them on a Kerbol science station that can get down to Kerbol surface and back up again to Kerbin orbit with plenty of spare fuel to do a fly-by of a few of the inner planets if I want to. Even if it were possible to get 12K deltaV with a nuke engine and a huge fuel tank (I'm not so sure it is in stock), your launch weight would be at insane levels, I doubt you'd even get it off the planet.
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