Comments by "mpetersen6" (@mpetersen6) on "Scott Manley" channel.

  1. In regards to Spin Launch. I remember an article in Scientific American close to 40 years ago. The article was on space weapons within the bounds known practice and reasonable foreseeable technology. One possible system that could be employed on low gee worlds such as Luna was a rotary throwing system capable of velocities up to at least Lunar surface escape velocity. Landing boosters in the Bahamas. Makes sense to me especially if it requires less fuel meaning a possible increase in payload mass or mission station keeping fuel. Given Space X's safety record in landings at the Cape I really do not think that the possible Bahamian government's opposition is going to be a major roadblock. Thinking about it it's actually a better launch location versus the Cape in terms of range safety.
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  2. Feet and miles are perfectly adequate units of measure. They may not be logically consistent in not being multiples of ten. But they work perfectly adequately as long you stick to one system of measurement. And just so you understand the inch/foot system is just accurate for use in just about any endeavor. The accuracy is in the standards and the measuring instruments. And yes I know that the inch is officially 25.4mm. And l am conversant in each system of measurement. Mainly because l refused to buy complete extra set of micrometers, calipers and other tools. And don't tell me about electronic micrometers and calipers. In general l don't like them and having the batteries die at inconvenient times is not fun. Plus the electronic mikes l had access to at work took special batteries. 🙄
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  3. ​ @MonkeyJedi99  You need a certain amount of financial and business management. But you also need management that understands your core business.
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  4. That's an idea that goes back a long way. The earliest designs were tested in vacuum chambers in the 60s. But then you still need temperature control units and heating elements probably.
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  5. One that a viable SSTO could be really good at is crew delivery. Especially if it could be robust enough to be Launch on Demand. Not every mission is going to require 100 tons to LEO. Myself l wish DARPA and the USAF would have pursued the Black Horse to at least hardware and flight test. That was a TSTO sort of. The first stage would have been a KC-10 or KC-135 that would refuel the Orbiter that would take off with a minimal fuel/oxidizer load. This would allow much lighter structure in the landing gear etc.
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  6. Once the program stretches into a new administration or Congress all bets are off.
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  7.  @johndododoe1411  I think they'd be better off using a fixed wing aircraft. Snagged the chute and winch into the cargo hold.
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  8. Falcon Heavy
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  9. Big surprise.
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  10. Those fairing must be under pretty hefty decellerstion.
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  11. There was also their experience building the Turbosuperchargers used in USAAF radial engines bombers and the two staged Allison V-12s used on the P-38. The early Whittle jet engines used compressor turbines similar to the ones used on automotive Turbos and an Axial Power Turbine. There was at least one other effort by Lockheed who had designed their own Axial Flow jet engine in the late 30s. There were a number of people around the world who had looked at building gas turbines for aviation use prior to the successful Power Jets but they were frustrated by the lack of high temperature alloys and the inability to make the designs light weight enough.
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  12.  @davidschwartz8125  Changing political requirements due to new administrations or changes in Congress have resulted in how many changes to programs. Or cancellations and starting over. Consider the SLS*. If it was to be limited to strictly heavy lift cargo they just could have dusted off the Shuttle C. But then everytime the government tries to save money by modifying something it seems like it costs more. *Senate Launch System. I'm all for putting all 100 of them onboard.
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  13. Of course the North American impact was by a giant feather pillow hence Lite Beer
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  14. And here I thought that was Chrysler
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  15. Every time they test a Starship at Boca Chica it's the 4th of July.
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  16.  @juliancrooks3031  Remember dinosaurs are still around. And they taste just like chicken 🍗🍗
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  17. I remember seeing some graffiti once that said 'free Huey Newton'. Newton was a Black Panther in the 60s. Somebody changed to 'free Huey, Dewey and Louie'
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  18. Corinthean leather for sure. Just ask Ricardo Montebalm
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  19. In some ways this reminds me of the orbital launcher that a German company wanted to build in Katanga. Literally dozens or more of identical super simple engine and tank assembly.
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  20. Its a technology that needs to be developed eventually.
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  21.  @aperson1  Well of course they're pretty light. Just as light as they can get away with. I'm surprised at how stable they are.
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  22. Why? Politics, pure plain and simple. The SLS, the NLS, the Shuttle C, the Jupiter all had to have 4 or 5 segmented SRBs to keep Morton Thiekol happy. And Utah politicians happy. Using the basic External Tank kept Lockeed Martin happy along with various politicans happy in Alabama, Maryland etc. Nevermind the tank had to be extensively redesigned given the thrust loads and where the payload mounts. For boosters I think you would just as well to contract for Falcon 9s. We know they work. We know they are reusable and we know they can return to the launch site. But there's those pesky politics sgain.
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  23.  @icegiant1000  The design and development team that came up with the computer mouse as showing it off to management. On hearing what the development team called it management's response was 'who's going to want a mouse on their desk'. Then they gave the idea away pretty much. That was Xerox. The stories a little more complicated than that of course.
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  24. In my mind the single greateet picture taken by an unmanned lunar mission was the Lunar Orbiter picture of Tycho taken at a low angle. It made the Moon an actual world in the publics eye.
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  25. Safety or hazarous equipment is going to yellow or possibly orange. As to the color of the paint used on machinery, tool carts etc. That's not a standard that I know of. The colors used today are better than the traditional industrial grey and greens of 60 years ago. Some of the color choice may simply come down to buying machine tools from the same manufacturers. Machine tool* builders do seen to have standard colors they use on their products. *this used to mean pretty much material removal aside from stamping, forming, casting and welding. Now machine tools include additive methods.
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  26. Was the vacuum a Dyson or Electrolux?
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  27. Better materials. Better manufacturing technology. The only thing with IC engines is the push to extract as much efficiency (and power) from them. This has resulted in engines that can be problematical as total time increases. Interference engines that destroy the engine if the valve timing gets out of time. Low friction piston rings that have a higher chance of failure simply because they are so thin. Internal components such as connecting rods made as light as possible. Plus they are made from scintered materials in many cases. Another problem with IC engines is owners not ignoring the maintenance schedule. Or in some cases going by the factory recommended oil change schedule. Which in some cases is 10,000 km or more between changes.
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  28.  @waynemapp6333  IMO SLS should never have been designed to be man rated. In fact I think we just should have built Shuttle C with the cargo front mounted and the engines in a return pod. Use Falcon 9 for crew launch.
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  29.  @TheReaverOfDarkness  The "investor" in this case would be a government sponsored science agency (NASA, ESA etc). This object is going to be moving fairly rapidly plus its orbit is highly inclined to the ecliptic. It is far less energy costly to change your orbital parameters in the plane of the ecliptic than to change your orbital parameters to an inclination to the ecliptic. Plus any flyby will most likely require a gravity assist of Jupiter or Saturn to bend the probes path in relation to the ecliptic. Most likely the vehicle would have to do a flyby of Saturn's southern polar regions. Just getting to Saturn takes time. Jupiter will complete just over 80% of one orbit between now and the objects closest approac. Saturn some where around a third. In this case a gravity assist may not even be possible given the time frame. In that case a low mass probe with the most delta vee that is achievable is what is needed.
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  30.  @92redferrari  Or a nautical mile. I agree Metric or more properly SI is internally logical although it does have units nobody uses. Decimeters anyone. And l hate when people use different systems of measurement on the same drawings products etc. Personally l wish the US would go metric fullbore. Not halfway like it has. We use metric for things that really matter. And traditional for stuff that is out in the everyday world.
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  31. Why do I get the idea that NASA cannot develop a damn thing anywhere near on time or budget. Is it political meddling? Engineering inability? Changing requirements? Or a combination of all three?
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  32. I thought of something sort of similiar years ago. Have the heat shield shaped as shallow conave cone. Have engine/s nozzle/arrayed in the center with the nozzles pointing so that the their exhaust flows over the heat shield. At the perimeter use a ring that can extend backward or a set of flaps that divert the exhaust gases. The idea is to use the whole heat shield as the expansion nozzle of the engine. Sort of a backward aerospike. The only area of the heat shield not used as the expansion nozzle is the cap over the engine assemblies. After all rocket engines work by expanding gases putting pressure on the engine assembly.
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  33.  @alphatrion100  As opposed to awarding the contract to Boeing, LockMart, Northrup Grumman or General Dynamics? Or they rely on the same development team as SLS.
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  34. The Paracone idea reminds me of the Monson Lung for escaping from subs. Yea it can work but is it more of sf something to make the families feel better.
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  35. To be honest I think anything proposed by NASA or any of the aerospace companies feeding the federal government trough will never be anything more than pretty pictures and animations. NASA's track record in the recent past has been less than stellar with the exception of the stuff done at JPL. Why is this? First it is because of incoming administrations changing goals and policy. Second it is because certain individuals in Congress care more about the jobs related to NASA Centers than anything actually getting accomplished in terms of actual goals, hardware being built and flown or much of anything else. LockMart, Launch Alliance and others are willing to play the game. The Shuttle was retired over 8 years ago and we are still no where near having any man rated system. I suspect Musk will launch man rated Dragons or even the BFR before NASA and the rest of the trough feeders are close to having a flight ready vehicle.
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  36. If we can't get images of the lunar lander descent stages I think JWST isn't going to show much
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  37. other way around Mica
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  38. Something like Spin Launch might work on a body with low enough surface gravity and no atmosphere. See my comment above. As to a Starlink constellation in orbit around Mars. Any serious manned Mars missions will require an orbiting communications constellation between the orbiter and the surface back to Earth. When thinking about manned Mars missions one major mission goal in my opinion should be to Phobos or Diemos to explore the possible production of propellant and oxidizer. If fuel production is possible that could be ramped up to the eventual construction of a fuel storage and refueling facility. Pumping fluids in low and zero gee can be a nightmare. One possible solution to that is if the fluid is stored in a bladder contained in vessel that can be pressurized.
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  39. Hancock does indeed go off the deep end. Carlson not so much. But there are some pretty intriqueing things around the world. Things that in a lot of ways don't make a lot of sense. Yonaguni (sp) off of Okinawa could well be partially worked by human hands. And just how long as it been underwater. Robert Ballard was working on a project for The National Geographic Society of the coast of Turkey looking for French and British warships lost during the Gallipoli Campaign. The ships weren't hard to find. But he found something else. Clearly artificial stone circles with stone piles/towers/altars at there center. This on the seabed that hadn't been above the waves for at least 8000 years. Right now the oldest constructions we know of besides the shelters built of mammoth bones and tusks is Gobekli Tepe and possibly the site in Indonesia on Java. These things just don't pop out of nowhere. There have to have been some precursor. I'm not saying cultures 13,000 years ago had technology as advanced as ours. But they weren't idiots either. Humans have been around for some 200K years at least. And in all that time nobody noticed that if we gather the seeds from this grass we like to eat and spread it in other spots we'll have another source. Or these roots are really tasty. Let's just try tossing some seeds around and see if they grow. I suspect that the traces of any "lost civilization" are out on the continental shelf's under 100 meters of water or more. There's another thing I find intriguing. And this is made possible with Google Earth. Look at ancient structures. Using the ruler tool draw a great circle through their main axis. You see it is quite common for them to be orientated towards the Poles. But not all. There is another group orientated towards a spot on Greenland at 47° West and about 83° North. And another group south of that. And a fourth group at about the southern tip of Greenland. And these are not structures in the same area. They are widely separated. And the number of them is more than just a few. Some individuals attribute this to the old idea of Crustal Displacement. I have a very hard time with that idea. One reason I have a very hard time imagining a mechanism that would initiate the process or stop it. Plus looking at the tracks of Hot Spot generated seamounts and islands to me it doesn't stand up. The odds that any random group of structures widely separated should be orientated to the same point seems to me to be highly unlikely. Is this the smoking gun for the Younger Dryas? I need to be convinced. If there is an impact that happened at that time I tend to think it would have been somewhere on the Laurentide Ice Sheet. One of the arguements against the Impact Theory is "where's the crater". Some of the arguements in favor are the nanodiamonds, sphericals etc. On top of that some of the non impact proponents point to the Younger Dryas being caused by the massive influx of melt water into the North Atlantic, the Arctic and Northern Pacific Oceans. The signs of massive floods is written in the landscape. The floods had to be meltwater. It had to have come off of the ice caps. What melted the ice. And does anyone seriously think that there ice caps would have been holding back the amounts of water needed. In many ways this can be thought of as a arguements between the Uniformitarianism school of gradual change. On the other side we gave the Catastrophism. When in reality they are both right. The Earth between Plate Tectonics and variations in it's orbit goes along moving continents. Going through Ice Ages. Building mountain ranges and wearing them away. And then the Earth has a bad day. A Mount Toba or Yellowstone erupts. A major igneous provinces spreads lava over a wide area miles thick like the Siberian or Decan Traps. Or like a bolt out of the blue a comet or an asteriod smacks us.
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  40. I am not an aerospace engineer but l have a few opinions about lander built for bodies with no appreciable atmosphere. 1) Given possible uneven surface and debris (boulders, rocks) and craters tall spacecraft with a narrow pattern are not a good idea. 2) If the lander is to be used as a manned habitat and research base design it to land horizontally. With wheels instead of just landing pads. Screw the weight penalty. Put drive motors in too. 3) If you are establishing a permanent base one of the most important first things to land is an excavator/bull dozer. You will need yhe excavator to provide loose regolith to shield surface structures. Plus the bull dozer to prepare your primary landing site.
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  41.  @221b-l3t  SLS Stationary Launch System
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  42. The one DARPA program I would of liked to see move forward was the air launched proposal to be launched from an F-15
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  43. With more launch vehicle builders looking at Liquid Methane I am surprised Lockheed/Martin didn't go that route. Yes H2 has better performance but it also requires larger tankage. Plus the storage issues with LH2. Also if you use the Lunar Gateway as a fuel depot you could ship the fuel up as water and a dense hydro carbon or even solid graphite. and manufacture the fuel on site at the Gateway. I could see the Gateway being primarily a fuel depot and supply site. Personally I see Methane as a more likely future for chemical propulsion systems. As to the RCS system. Why not use H2O2 at about a 90 to 95% solution
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  44. In the future Dawn along with various other space probes may be recovered and wind up in an equivilant of the Air & Space Museum
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  45. ​ @Andy_T79  We all know just what the big draw for space tourism will be.
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  46. Metric is no more or no less accurate than any other system of measurement. The accuracy lies in the standards, the instruments and traceability of the standard masters used in the field to calibrate sad instruments. But yes l agree Metric or SI is more logically consistent. As somebody who had to do inspection work on machine components designed using the Metric system and the associated tolerance bands for fits doing all the measurements with inch calibrated micrometers and having to do the conversions was a pain.
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  47. So basically they want to build a 21st century V-3. The last guy whowanted to build a launch gun got whacked by the Israelis. Do not go looking for funding in the Middle East.
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  48. Catches payloads returning from orbit is nothing new. USAF in the 60s catching film canisters returned from Corona reconnaissance satellites in the pre digital imaging days. Instead of using a helicopter I think Rocket Lab might be better off using fixed wing. At the same time the US also developed a system to allow the pick-up of individuals from the ground by fixed wing aircraft in flight.
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  49.  @grn1  One reason for using light colors is any leaks in hydraulic systems will show up like a neon sign. Personally I love hydraulics in the right application. Precise control and clamping pressures. The downside is leaks. Because all hydraulic systems will leak eventually. Be it through wear on hoses, seals or the connections. Often on the connections it is due to vibrations being transmitted through the system. Flared tube ends (flat or conical) are more prone to leaks. But systems using ferrules will leak also. One reason is any slight imperfection in the fit between the ferrule and the fitting body.
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  50. We could have done artificial gravity testing in LEO if we had wanted to.
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