DerekL1963

Nope. MM-III still has thrust termination ports* because you still have the same problem - how do you reach a target at less than the maximum range of the missile? Basically, ballistic missiles are designed such that if you burn the final propulsive stage to exhaustion the warhead (or bus) is thrown to the missile's maximum range. While bus energy can be used to extend the footprint along the range axis, there isn't sufficient energy to extend the range of the bus significantly. (And any energy expended for range extension isn't available for cross-range expansion.) *ref: http://ed-thelen.org/Minuteman.pdf pg 89, http://www.au.af.mil/au/awc/space/primer/us_missile_systems.pdf pg 17-9, not to mention the title of the animation you linked to.

Just because someone is interested in producing something, that doesn't mean there are buyers for that something. Back in the 60's plans for optimistic space futures abounded. And in the 70's. And in the 80's. And... well, you get the picture. Plans are a dime a dozen. No, correct that, there's a vast oversupply of plans and they'll pay you to haul them off to the recycling center. What there's a shortage of is actual markets and customers willing to shell out the megabucks needed to execute the plan. More viable is not the same as actually having customers. Space tugs are only useful when you have something to tow, and a destination at each end. It's not lack of cheap fuel that's holding them back, it's lack of a point. The same thing goes for asteroid mining... lack of customers for the end product is the problem, not lack of cheap fuel. That's the basic problem that your scheme fails to address - for it to become viable, someone else has to spend huge chunks of cash to provide you with a market. Until you solve that problem, all we're doing here is (for the nthousandth time) indulging in intellectual masturbation.

Assuming NASA (and/or others) are buying. And buying in sufficient quantities to fund the whole affair.

True. But so long as it re-oriented and de-orbited, they can claim (with a straight face) that Falcon performed according to plan. And no doubt in my mind the clearances and briefings to the launch crew made it quite clear that's all they could say.

You can turn them off either way - by venting the forward dome or by blowing off the nozzle. The latter is less well known as the LGM-118 Peacekeeper is the only missile known to have used it operationally. One way, extensively discussed here, is to use thrust termination. The other is trajectory shaping - for example burning to left for a little bit and then burning to the right to null the velocities and correct the induced error consumes more delta-v than simply burning straight. This is known a GEMS (Generalized Energy Management Steering), and was used by Trident-I and is used by Trident-II. This article discusses using GEMS to control speed (and thus range) and has a picture of the resulting trajectory.

Government owned vessels such as these are a special case. There are (rare) situations, where a civilian ship can be considered completely abandoned and "finders keepers" applies. (The property is not required to be returned and salvor is not due any compensation.) This is not true of a government owned vessel, which remains the property of said government unless and until the government specifically and intentionally relinquishes ownership. It was under this theory that the US Government successfully claimed title to CSS Hunley. (Since the USA was the successor government to the the CSA, and neither government had ever relinquished title.) To wrench the discussion back closer to topic, this is why the Government intervenes whenever something from Challenger or Columbia is discovered - both vehicles are still US Government property. No, there's nothing stopping someone from taking possession, but that's not "finders keepers". The quote from Wikipedia is incomplete and misleading - if the recovered property still has a legal owner, the salvor is required to relinquish custody to said owner, and the owner is then required to pay the salvor appropriate and just compensation. If the salvor does not relinquish custody, the owner then has legal grounds for either suing the salvor for the return (without compensation) or having him charged as a thief. The general idea is to encourage and reward those acting in good faith from those who are not.

You should look at the first operational carriers of the 1920's then. The era of "cut down merchant ships" was precisely two carriers, The Royal Navy's Argus and the USN's Langley. (The only other flat-deck/no island carrier of the era was HMS Furious, which wouldn't come along until much later.) The Eagle (tested with a starboard island in 1920, entered full service in 1924) was the UK's 2nd operational carrier, the Béarn (1927) was the French's first carrier, and Lexington (1927) was the USN's second carrier - and all had starboard islands. That's a considerable misunderstanding of the situation. (To put very mildly.) Ships docked with their left (or port) side to shore (or pier or quay) in the era when the steering oar (the steorbord) was on the right (or starboard) side of the vessel. That era was essentially over for large oceangoing vessels by the mid-late 1500's when the tiller replaced the steering oar. (Tillers eventually evolved into rudders as we know them today.) Tillers are on the centerline, and the ship may dock whichever way it finds convenient without risk of damage to the steering gear. With the era of ships being required to dock to port being the better part of half a millenium in the past, it played no role in the design of the carrier. 0.o The earliest carriers had centerline elevators! (If they had elevators at all.) The first deck edge elevator was installed in USS Wasp (1936) - a decade after starboard islands became standard.

Neither the French nor the Russians developed the Camel or invented the aircraft carrier. And, FWIW, the Béarn followed convention - her island was to starboard. Ditto for every Soviet carrier or pseudo carrier.

It's not the percentage that matters, it's the partial pressure. The presence (or absence) of any other gas is irrelevant. At Terrestrial sea level pressure, such a mixture is slightly oxygen rich compared to ours - and would support combustion. Somebody with better math and chemistry would have to figure out at Kerbin pressure.

Left turn actually, that's why aircraft carrier islands are to starboard.

Do you think the laws of salvage are nothing but "finders keepers"? On the contrary, it's because of the laws of salvage that you can still own a ship that sinks. Something in space however... that gets complicated because there isn't a body of law to fall back on. And there's the catch that by treaty, the State that launched or authorized the launch of something retains responsibility for that something. What form that responsibility takes has never actually been worked out.

Let's see... the first is cancelled project, because it wasn't a viable weapon. The second is something rumored to exist. But off topic from the point of the thread either way.

Gemini and Apollo were NASA programs, and not relevant to a USAF training film. Not to mention neither one faced ABMs during re-entry, nor were planned for ballistic CEPs of only a couple of thousand feet. Both Titan II and Polaris A3 served into the 1980's, A-2 was still in (limited) service. Though Polaris A-1 and A-2 (like Titan II) carried their RVs unshrouded... A-3's reentry vehicle design (sphere-cone-flare) was missing from the film though. There were no (US) MIRVs in service in 1965. (Polaris A3 was MRV not MIRV.) When MIRVs did enter service, they were anything but classified - the capability was widely advertised. (You can't deter an enemy or reassure a populace without publicizing capabilities, at least in general terms.) In the same way, that the US was extremely successful at miniaturizing nuclear weapons was also widely advertised as a sign of our prowess. The USSR''s lack of such ability was also widely advertised by the West to denigrate their accomplishments.

Some of things in there, I bet this was classified back in the day. And interestingly enough, the USAF (and USN) were moving to conical and sphere-conical warheads at the time - both shapes noticeably absent from the film.

That's all very nice... But has nothing to do with anything I said or with the topic at hand. Boundary layers and fluid motion only apply where the atmosphere is thick enough for those phenomena to occur - many, many miles below the altitudes under discussion. Which isn't a problem, because tethers aren't intended to provide control.

Uhmm... if there's no static pressure, then why do satellites deorbit due to drag in the first place? (Answer: you don't need static pressure to create drag.) They've been tried, no success (mostly due to tether deployment problems).

No. Use pulse lasers, by vaporizing a few mm of material you create a shockwave the same as if you'd let off a couple of pounds of TNT on the rock face. (This is the same damage mechanism that anti-missile lasers use.) The problem is that untamped explosives on the surface aren't terribly efficient at breaking up rocks, there's a reason why they drill and emplace the explosives deep inside the rock.

I don't get why all of space history should be shoehorned into one thread. Then it's not a space history thread.

Well, it's theoretically a thing. Experiments with using actually using tethers on orbit have not in general fared well. If anyone's actually used one, I can't find any traces thereof. (Lots of bold predictions, no actual data.)

Why? And why the silly poll? While you can avoid toxic partisan politics, you can't discuss the space race without bringing at least international politics - because those form the whole basis of the space race.

Ever watched someone try to balance on ice skates or roller skates for the first time? The wetware assumes high friction contact between the feet and the surface it's standing on. (Included in that assumption is the assumption that there's a surface involved.) So, zero friction and no surface... means you're way outside the wetware design envelope.

Oh, that's an easy answer - all you'll accomplish is diluting your fission fuel. The pressures/temperatures inside such a reactor aren't anywhere near fusion territory.

I can't even figure out what such a thing would look like... the materials that fizz don't fuze, and vice versa. So I'd say, it's not possible to build a hybrid reactor of that nature. (And no, Teller-Ulam isn't a reactor and doesn't count.)

Flights are expensive. And it's not impossible they thought they had a workable solution that didn't actually work. This stuff happens, BTDT.

That's the thing - it's not an incremental mission. It's a series of tenuously connected missions. The two are not the same, and the latter doesn't generate the sense of "urgency" the former does. It's "clandestine" nature is more likely to trigger backlash than funding (IMO). The upshot of this is that they literally have no idea how to retrieve the sample, how to get them into orbit, how to recover them on orbit, and finally how to return them to and recover them at Earth. All of these things are impacted by the design of the 2020 Rover... Or to put it simply, design decisions are being made today with no clear idea how they'll constrain future missions that are currently barely BOTE.