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Brane Craft
- partycoder 11y agoToday is the anniversary of the Vostok 1 launch, the first manned spacecraft. If anything will make it to the front page of Hacker news today it should be that.
- captn3m0 11y agoStarshot is on the first page, and apparently they timed the PR for the anniversary. https://news.ycombinator.com/item?id=11480840 https://news.ycombinator.com/item?id=11480840
- mattbeckman 11y agoAs CubeSats and FemtoSats are picking up support, we need LEO trash collectors even moreso.
- grinich 11y agoLEO trash collectors doesn't the atmosphere do a good enough job? seems that most things in LEO will decay within a few years
- mdorazio 11y agoNot quite. It really depends on the shape of the orbit and density of the debris. It could be months, but it could also be decades to de-orbit naturally. Also, the bigger problem is that the amount of debris is growing faster than the decay rate [1] so the problem is getting worse over time. [1] http://www.nasa.gov/mission_pages/station/news/orbital_debris.html http://www.nasa.gov/mission_pages/station/news/orbital_debri...
- CapitalistCartr 11y agoUnfortunately no. The curent amount is already serious and, if we were continue at our past rate, we'll make space inaccessible. Orbital Debris Quarterly is a good resource on the subject. http://orbitaldebris.jsc.nasa.gov/newsletter/newsletter.html http://orbitaldebris.jsc.nasa.gov/newsletter/newsletter.html
- patrickyeon 11y ago(I'm not an orbits expert, but I do work for Planet Labs, and we're sending up piles of cubesats.) The actors puting objects up in orbit are trying hard to be good neighbours these days. Our cubesat missions are designed such that should we completely lose control over a satellite the orbit will naturally degrade and re-enter the atmosphere on a ~10 year time scale. Our hardware deployed from the ISS is gone in less than two years. It's my understanding that it is required of us (and most groups in general) to plan our missions such that they will naturally de-orbit within 25 years.
- grinich 11y agoThanks for that link!
- sarreph 11y agoIt's amusing to see "LEO" referenced twice in one day on HN, where the first time it was mentioned earlier[0] someone confused it for 'low earth orbit' when the author meant 'law enforcement officer'. [0] - https://news.ycombinator.com/item?id=11479709 https://news.ycombinator.com/item?id=11479709
- taneq 11y agoI've long maintained that TLAs have become almost completely useless outside of extremely tightly scoped discussions. The namespace is just way too polluted.
- jessaustin 11y agoIn both cases mentioned, the discussion has been of sufficiently limited scope. Some people will ignore any context. b^)
- scentoni 11y agoUntil we get into discussions of law enforcement officers working on a space station in low Earth orbit.
- anon5446372 11y agoBane craft - ah, you think darkness is your ally?
- state 11y agoI wonder who does the 'graphic depictions' for NASA. Must be quite fun.
- tempodox 11y agoI would apply for that position at once.
- e0m 11y agoMore things should be described as "propagating through spacetime"
- allisthemoist 11y agoI mean aren't we all?
- cwh 11y agois that a feature of Route53?
- taneq 11y agoIt's also a feature of copper wire. And bees.
- n0us 11y agospacetime.js A new event propagation system available on npm today under the package name "nasa"
- maaku 11y agoElon's don't propagate through spacetime. They pull the frame of the universe I the opposite direction.
- dcgoss 11y agoI think we should have a new unit of measurement called the Elon. "He traveled about 45 million Elons at a rate of 25 kiloelons per second"
- whatifbeans 11y agoLooks like a magic carpet to me.
- sarreph 11y agoIt'd be pretty cramped onboard the 2D Branecraft
- inopinatus 11y agoYes. It is too small. Therefore: The relevant Hugo winner has you & thousands of others uploading your personalities into on onboard "neural mesh", resulting in everyone calling it the "Brainship". An in-voyage accident due to forgotten space junk sends you somewhere unexpected in space and/or time. During the trip the onboard community fragments and develops in a petri dish of experimental post-corporeal societies that promptly go to virtual war over control of the craft. The Bra{in|ne}boat encounters strange new lifeforms, which by a series of loosely connected plot devices involving convoluted theoretical and/or fictional mathematics, enable one small motivated group on board to seize control and return the device to Earth, over the objections of another group. In the intervening thousands of years, humanity has evolved radically and is facing destruction due to techno-industrial political forces wielding unimaginable power. The inhabitants of the Brainevessel join forces and use the wisdom and/or alien friends they gained during their epic voyage to save humanity, and the warring factions are subsequently reconciled and redeemed. One faction stays behind to help humanity recover, whilst the other goes on an unspecified voyage back to the stars aboard the upgraded Mindyacht. The End. (c) every science fiction author since Homer.
- _AllisonMobley 11y agoI like it.
- taneq 11y agoSounds... Stross-y. :)
- T-A 11y agoYep, that was pretty much Parts II & III of "Accelerando": https://en.wikipedia.org/wiki/Accelerando https://en.wikipedia.org/wiki/Accelerando
- ChuckMcM 11y agoWell it is out of the box thinking, not sure how practical it is though. Sadly a paper on "Brane Craft" does not show up on The Aerospace Corp's website, although Siegfrieds work on cubesats does (https://www.google.com/url?q=http://www.aerospace.org/wp-content/uploads/2015/04/Think-Big-Fly-Small.pdf&sa=U&ved=0ahUKEwjn85_nkorMAhUBU2MKHVNqCjYQFggKMAM&client=internal-uds-cse&usg=AFQjCNHfgX3casQ0ChFAOfnTh6vT6InQMQ https://www.google.com/url?q=http://www.aerospace.org/wp-con...) One of my favorite "low cost / unconventional" de-orbit ideas was candle soot clouds. Basically a cloud of carbon black that is deployed in orbit, it coats objects that pass through it asymmetrically resulting in asymmetric thermionic emissions when exposed to sunlight, creating a small net impulse which pushes the stuff out of orbit. Not sure how you would prevent it from killing stuff you wanted to keep though.
- LeifCarrotson 11y agoWouldn't that only work if the object did not rotate at all?
- ChuckMcM 11y agoAs I recall the paper covered rotation (all space junk seems to have a rotational component) the energy comes from solar insolation which is always in a consistent direction relative to the orbital motion.
- noobie 11y agoJust out of curiosity, how do satellite launchers account for space debris[0]? 0.https://upload.wikimedia.org/wikipedia/commons/a/a1/Debris-GEO1280.jpg https://upload.wikimedia.org/wikipedia/commons/a/a1/Debris-G...
- danielvf 11y ago"Space is big. Really big. You just won't believe how vastly, hugely, mind-bogglingly big it is..." A lot of it comes down to things just being far apart. We're used to the surface of the earth - a 2D surface, but space is 3D. There's orders of several orders of magnitude more room and not a lot of objects in it. Secondly, the orbits of these objects are tracked and in a database. It's a pretty easy task to check if your planned launch path comes near anything.
- madaxe_again 11y agoSpace is big, low earth orbit isn't - it's easy to end up with a runaway debris cloud that completely blocks access to space. Space will still be really, really big, but short of Jeltz showing up, kessler syndrome will close our access to space.
- danielvf 11y agoKessler is overhyped. The lower half of low earth orbit isn't a problem because everything there falls to earth in a year or two unless it is actively keeps itself in orbit. Outside of LEO, there's massively more room, and massively less stuff. So the only area we need to consider is "high" LEO. As a thought expiriment, consider the worst case - a hyper intelligent, pan dimensional being disassembles all spacecraft in high LEO. let's assume that's 1,000 US tons worth. ( I have no idea.) if these spacecraft pieces were spread into a sphere the size of the earth, that would be 1/40 billionth of a cm thick. Since a sphere doesn't orbit, let's turn it into lethal 1cm cubes, all magically evenly distributed, orbiting at the same altitude, magically not colliding. That's one death cube every 4 square Km. What are the odd of flying a rocket through that layer? Pretty good actually. The layer is only certain death if you stay in it. We'd still have access to the solar system, geosynchronous orbit, and mid/low LEO even in the alien intelligence worst case Kessler syndrome. ( I have only worked this out on the back of a napkin. Corrections to math appreciated)
- Aelinsaar 11y agoThe description seems totally at odds with the babble about 2D Branes.
- RIMR 11y agoThis is one of those things where I am not sure if I just don't understand the core concepts, or if the person talking to me is a complete nutter. Isn't a 'brane' a mathematical object? Is there any basis in science for turning a physical 3d object into a M2-Brane? At first read I thought he was just talking about a space probe in the form of a thin sheet that could propel itself in a novel way. Now I think he's talking about dropping the ship out of the third dimension. Can anyone here ELI5?
- chiaro 11y agoI assume it's some kind of solar sail. https://en.wikipedia.org/wiki/Solar_sail https://en.wikipedia.org/wiki/Solar_sail
- foobarbecue 11y agoNope. They describe the propulsion quite clearly. It's solar panels and an ion drive. The material they are ionizing is a liquid stored between the two sheets.
- smaddox 11y agoSounds like they just want to thin down a solar-powered ion-thrusted craft to the engineering limits, in order to maximise the collecting area.
- cyphar 11y agoBranes are used in string theory, but to be fair, that field of physics is basically maths.
- tempodox 11y agoI can't decide whether this is a late April fool's joke or just an unorthodox concept.
- philip142au 11y agoHow does it do propulsion?
- stuaxo 11y agoAnd here I was thinking it would be a craft to travel the multiverse.
- madaxe_again 11y agoNice idea using them for clearing orbital debris, but the $1bn cost of doing it "conventionally" seems a reasonable price to pay for continued access to space. If we don't do something, we will end up trapped on this ball of rock by lethal kessler syndrome. Why isn't there legislation mandating that space operators tidy up after themselves? Wait, stupid question, we can't get that right even on earth.