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Is Apollo 11’s lunar module still in orbit around the moon? [video]
- netman21 5y agoThis is great. Love the encouragement at the end for amateur space research.
- detritus 5y agoI had "Hullo, it's Scott Manley here.." going around my head before the YouTube page opened, confirming as much :)
- SideburnsOfDoom 5y agocan we get a "tl;dr" or a "I'm not going to watch 11 minutes of video to find out if it's a yes, no or a maybe" ?
- icegreentea2 5y agoIt's a maybe. Simulations (including some degree of initial condition randomization) imply that the orbit may be sufficiently stable.
- dade_ 5y agoIt provides an overview of open source software from NASA that calculates that it is possibly still in orbit.
- a4isms 5y agoUp to you entirely, but for most of the things on Hacker News, the answer to any one question is not very interesting, but the process of answering that question is very interesting. OG Game Developer Chris Crawford, when discussing the design of his economic/geopolitical simulation game “Balance of Power,” said roughly: “The actual GDP of Ghana is not interesting. The mechanisms that drive the GDP of Ghana are very interesting, and that’s what the game tries to explore."
- dragonwriter 5y agoThat's kind of a weird claim, because other than direct economic and military aid and pro-/anti-government military intervention from superpowers and trade and defense agreements with them, BoP didn't surface any potential drivers of GDP, nor GDP itself, nor any effects of GDP other than stability and geopolitical alignment of the government. Whatever was going on underneath, BoP was much more of a geopolitical than economic simulation in what was exposed to the player.
- a4isms 5y agoI don’t disagree with you, but he made the quote in the context of explaining why he was trying to make a game about indirectly creating outcomes, which in the major revision went multi-polar so that countries had their own tensions between themselves independently of the two major powers.
- SideburnsOfDoom 5y agoThank you. There are also 1-para summaries here that provide not just the answer, and some insight into the whys of it, but also reasons for when to follow up by watching the whole video. That you did not.
- serf 5y ago"Can I get a tl;dr about the article?" "No."
- SideburnsOfDoom 5y agoI am going to write an article about "Should you use yes-no questions as the titles of articles about complex systems? The answer might not surprise you.". In fact, let me make it a 15-minute video instead. That will really help people get to grips with it.
- a4isms 5y agoVery true, but if you want to ask a question and only get an answer to your question, that’s StackOverflow, where moderators are there to ensure that questions and answers don’t become conversations. On a less-structured forum like this, the XY Problem is in full-effect: “How do I X?” “You seem to actually want to Y, and X actually isn’t a good way to achieve Y.” Classic example: “How do I ace a whiteboard coding test?” StackOverflow: “Be sure to ask questions about requirements. State all your assumptions aloud. &c. &c.” Hacker News: “Walk out. They’re idiots and you don’t want to work for them.”
- tgsovlerkhgsel 5y agoThe initial assumption was "no" due to the moon's gravity field having strong local variations that usually destabilize orbits and cause orbiting objects to crash into the moon. However, simulations based on original data and hundreds of variations to account for uncertainty show that there is a high likelihood that the orbit remained stable for at least 10 years (not sure if they actually simulated until today). There are many other things that can influence an orbit and simulations aren't perfect, so it's a "maybe".
- SideburnsOfDoom 5y agoThank you, that's interesting and concise.
- dredmorbius 5y agoAdding to this: there are a few other conditions which apply. The initial orbital parameters may not be accurate (there are known major errors), there are volatiles which were onboard which may have outgassed (affecting trajectory) or exploded (affecting integrity). The orbital mechanics (and simulator) elements are quite informative and well done. But there's reasonably good odds much of the ascent stage is intact and in orbit. Other Apollo missions are mentioned. Apollo 10 (which executed a near-surface approach but no landing) executed a burn resulting in solar orbit insertion with a highly probably matching asteroid having recently been found. After Apollo 11, subsequent ascent stages were intentionally directed into lunar terrain as part of seismographic (selenographic?) studies. Manly does a good job of presenting significant credible information. I'm not an uncritical fan of video but this one rewards attention.
- baq 5y agothis is Scott Manley, go watch this and be prepared to watch a few more hours of his other videos.
- ncmncm 5y agotl;dw: Things left adrift in lunar orbit tend to crash into the moon before long both because the moon is gravitationally not spherical, and because the moon is in a complicated dance with the sun and the earth. But there is a substantial chance that it hasn't crashed yet, and it's interesting why.
- MayeulC 5y agoRight, this is a bit clickbaity so I was skeptical at first, but it's a Scott Manley video, and it's pretty interesting to watch, with a few comments on the tools used, and simulation visualizations.
- rbanffy 5y agoGreat. Now we should fund an effort to locate it and, at some point, recover it and tug it back to either the surface, to start a museum near the first settlements, or LEO, to join the ISS as artifacts of an orbital museum.
- techdragon 5y agoBetter move quickly because we plan to de-orbit the ISS soon… Personally I think we should just tug the ISS up a decent bit higher (50 to 100 year decay?) on the final crewed mission, and then mothball it. So we have enough time to build a big enough, actually permanent, space station that the ISS can be put inside that as a museum exhibit. I also think Hubble deserves a robot tug boost too because that’s another priceless artefact with a retirement plan of “burn up over the South Pacific”
- rbanffy 5y ago> I think we should just tug the ISS up a decent bit higher Both are really bad ideas. Every time something hits the ISS there will be some high-speed fragment coming off on a weird trajectory. The higher the ISS is, the higher the chance those fragments will not deorbit themselves. Everything parked in orbit is a potential source of high-velocity impactors for everything else parked at a similar altitude. It'd be nice if we could deorbit it whole inside the cargo compartment of a "Galaxy class SpaceX Starship", much bigger than the current one and going to space on top of a Ultraheavy, composed of 3 attached Superheavy boosters. We could also surround it with lots (and LOTS) of inflatable heat shields to slow it down and then parachute it to a sensible landing site. If we get Starship functional before the ISS's demise, we can even think of doing that kind of stunt. Imagine it whole hanging from the ceiling of a museum. Or, if a propulsive landing is possible, imagine it hanging from the ceiling of a museum in Shackleton City. ---------- The Hubble would also need a visit to upgrade and replace some components too. Maybe sending a Starship to bring it back, then relaunch it after an upgrade on land. It's crazy how the economics of Starship make even ludicrous ideas like these look perfectly doable.
- techdragon 5y ago
- dnautics 5y agoHow cool would it be to attach an ion engine to it, bring it back, aerobrake it gently back into earth orbit, scoop it up with a starship maw, and land it?
- new_realist 5y agoSurely if it's still in orbit, is is reflective enough to be occasionally observed by telescopes on Earth.
- lisper 5y agoYes, if you know where and when to look.
- dredmorbius 5y agoMore likely by radar reflection, as the module has metalic components with a high reflection signature, as discussed in the video.
- peter303 5y agoThe Moons gravity is more lumpy than the Earths due to variety ofnear surface terrains. I doubt whether a closein orbit would be stable for a long period of time. Some of the modules were smashed into the surface to provide seismic sources of a known momentum.
- GhostVII 5y agoThats what this video is about, determining if the specific orbit the module is in is stable or not based on the gravity lumpiness
- mrfusion 5y agoWhy just 11? Why not the first 10?
- croutonwagon 5y agoThe first 10 Apollo missions didn’t go to the moon. They were baby steps to get 11 kids n the more on.
- euroderf 5y agoNot to the surface.
- frosted-flakes 5y ago9 and 10 orbited the moon, and 10's lunar module came within 50000 feet of the surface.
- 8bitsrule 5y agoThe story of the PFS-1 and -2 sats released by Apollo 15 and 16 may predict the fate of 'Eagle' ascent. (PFS-2's initial orbit was 52x66 miles.) https://web.archive.org/web/20090725122356/http://science.nasa.gov/headlines/y2006/06nov_loworbit.htm https://web.archive.org/web/20090725122356/http://science.na...