how did this shoddy looking thing that looks like its made out of tinfoil lift off from the moon and fly back to earth?
How did leaving the moon work?
The CM was whizzing around the moon while they were down in the LM.
Then the LM went up, presumably in an arc to get into orbit?
And then they played catchup with some booster rockets until they docked?
So I guess some timing was required to rendezvouz?
Well first of all, it didn't fly back to Earth, it just flew back to the moon's orbit. The command module flew back to Earth.
Second, it was most definitely not "shoddy." It is built as lightly as possible, true, and it doesn't have to be aerodynamic because it only operates in vacuum. The "tinfoil" is actually an extremely sophisticated thermal insulation, made of many layers of different materials, many of which didn't exist 10 years earlier.
As for why it can lift off from the moon without the giant rockets needed to lift off from the Earth, it's mostly because the moon is a much smaller gravity well. The size of the rocket you need is not linear. The more acceleration you need, the more fuel you need, which in turn requires more fuel, etc. Lifting off from Earth, most of the fuel is used to lift the fuel itself. Another factor is the fact that there is no atmosphere to push through at thousands of miles per hour.
Not terribly well, they aimed to go into a phasing orbit and slowly met up with the CM after going round the Moon a few times, plenty of time built into that to make adjustments as necessary.
You need fuckloads of fuel to make it all the way back to the earth, especially when you don't have a bigass rocket thats taking you there. So where is their fuel tank ? Where are the boosters ?
Mass, empty (2,150 kg)
Mass, fueled (4,700 kg)
It may look like a toy, but it was well designed, weight skimmed to work with lunar gravity, grabrails and ladder only just able to support astronaughts weight etc.
That's the thing - while on moon they realized they didn't have enough juice to come back to earth. So they stripped most of the ship and replaced parts of it with what you described as tinfoil. On ascent the acceleration was still too low, so they breached a dock adding some velocity. Then to correct the course one of the astronauts had to cut a hole in his suit's glove and escaping air gave him enough thrust to set this ship on a proper course to earth. Whole thing was crazy.
It's not that hard to calculate a rendezvous trajectory, even with basic computers. Pic related if you actually want to learn this shit. It's like 6 bucks.
>The moon has so little gravity you could throw a stone into its orbit from its surface.
I hope you're joking but just in case you're not, the amount of delta-v required to enter low lunar orbit from the lunar surface is 1.73 km/s. I'd love to see someone pitch that fast. Granted, that's a hell of a lot less than the 9.4 km/s required to enter LEO from the surface of the Earth.
>easily understood by playing Kerbal Space Program
Fuck that, I had to make a new game because I killed my entire Kerbonaut corps inside of two hours. Orbital rendezvous are hard as fuck
Assuming you are capable of getting near your target craft and reducing relative velocity to the point you effectively have the two vessels parked next to eachother (the easy part), this is how I dock.
1. Make sure the fuel of the orbiter you will be maneuvering has a fuel tank setup which keeps the center of mass fairly static.
2. Make sure your RCS thrusters are evenly spaced from the center of mass, and as far from the center of mass as possible (better leverage)
3. Set the docking port you wish to attach to as the target (instead of the entire craft). Select the port on the vessel you are maneuvering with and click "control from here"
4. Lock your control point to the pro-target marker on the nav-ball (there are selection icons on the left side of the nav-ball when you have SAS turned on)
5. Use RCS controls (I,J,K,L, and H,N) to line up your prograde marker with your pro-target marker (requires continual adjustment usually).
6. Approach at .5m/s until you are about 5m from target port, then reduce to about .2m/s to avoid bouncing off.
It's harder than most other shit churned out these days.. The math of stripping the ascent vehicle also mostly works out, although it has calls for some odd design choices. e.g. Having the ascent vehicle be Two Stage to orbit when SSTO is possible. The math also implies a specific impulse that's a bit higher than what would be expected for the given fuel mixture. For someone that wasn't a rocket scientist, they did an acceptable job.
The glove thing though was completely retarded and I still can't believe the movie turned that joke into an actual means of resolving the plot. After they blow the hatch in the movie it feels like a different director showed up and they gave up on the whole, "Let's avoid Hollywood bullshit" the film had tended towards before then.
Flight plan says orbit insertion at 124:30 (7 min after liftoff) and docking at 128:00, three and a half hours later. The Command Module designer was Maxime Faget and the Moon smells like spent gunpowder, they said.
>The moon doesn't have any atmosphere so it can't smell like anything
Ignoring the fact that the moon doesn't have air, so you can't breathe anything either. Or that the astronauts couldn't take off their helmets without dying. Or that you *can* smell things without an atmosphere, you fucking idiot. Are there no smells on the ISS?
A few tips for Rendezvous.
1. If the craft you are maneuvering needs to catch up to your target, put it in a lower orbit, by about 10 - 15km. (the lower the orbit, the faster the orbit)
2. If the target needs to catch up to the craft you are maneuvering, put it in a higher orbit by about 10 - 15km.
3. Accelerate time until one of the encounter indicators reads about a 15km separation.
>You want to start manually augmenting the approach when the distance reaches about 15km and is dropping, so you have momentum on your side.
4. When you reach the point where the distance between you and the target craft reaches 15km, find the prograde marker on the nav-ball (make sure your nav-ball is in "target mode" by clicking the text on the top that indicates orbit, surface, or target) You want to pull the prograde marker onto the pro-target marker by accelerating toward the side of the protarget marker opposite of the prograde marker.
> accelerating pulls on prograde and pulls on retrograde.
> a good rule of thumb for approach velocities is 1m/s per 10m separation (should be going 100m/s with a 1km separation, 10m/s at 100m separation)
5. To slow your approach in a controlled fashion, orient your craft so the 'front' points retrograde, push your retrograde marker over your retro-target marker by accelerating toward the side of the retrograde marker opposite the retro-target marker.
>acceleration pushes retrograde and pulls prograde.
I hope this helps, got work to do (weed) but I will keep this thread open if any questions arise I will respond in an untimely manner (weed)
Addition: When looking at the navball you can think of the line that interects your manipulations point, pro/retro-target, and pro/retro-grade indicators as a lever.
Thats the way I look at it anyway. Your manipulation point is the force you apply to the lever to manipulate the pro/retrograde marker, which is the load you are lifting with the lever, in order to deliver it to the pro/retro-target.
It was built plenty strong enough to withstand whatever net acceleration it was under (obviously greater than 1/6 G), but didn't need to be designed around aerodynamic considerations (as the moon has no atmosphere, and the LEM wasn't designed for atmospheric reentry). Which means really the only forces acting on it are the weight on the landing gear and the thrust from the engines. No need to worry about building parts of it from flimsy materials that would get torn off flying through the air at 100 mph.
They were able to save on fuel by making it multi-stage, the descent engine and its empty fuel tanks were left behind. An the interior was pretty cramped, it wasn't exactly made to be comfortable for long durations.
"Rocket science" is actually fairly simple mathematically, the hardest part is just making sure all your figures (weight, propellant mass flux, center of gravity, planetary orbits) are correct. And computing power is really a non-issue anyway if you calculate everything in advance and stick to the plan.
>end of post
>"stopped reading right there"
I sincerely hope this is bait.
It's daytime on the moon. The rocks are as bright as rocks on earth. Stars are very dim and if your eyes are adjusted to see the ground in broad daylight then they can't see the stars.
On a bright sunny day, if you shine a torch at the ground the sun light is too bright in relation to see the light of the torch.
But at night, the light of the torch seems very bright.
Why are you people so eager to dismiss these videos as fake all the time ? How do you just ignore the footage and witnesses for the moon landings and things like UFO sights with tons of videos ? Not everything is fake you know. Skepticism is fine but denying everything is just pointless.
>The "tinfoil" is actually an extremely sophisticated thermal insulation, made of many layers of different materials, many of which didn't exist 10 years earlier.
thats why i wear it on my head
There's a big difference between "the math is too hard for me" in orbital rendezvous (something we know has occurred many times, unless there is a massive conspiracy that everyone is in on), and "our current understanding of science indicates that this is physically impossible" in FTL and your woo drives.
Kelvin was completely correct in the context of Newtonian physics though.
Predicting that Newtonian physics were accurate only on a tiny (astronomcally speaking) frame of reference and that the idea of mass and Gravity was fundamentally wrong was a bit beyond his time (although not too long)
The stars are everywhere, bro. The problem is that the exposure on the camera is far too short to pick up significant light from them, so they appear no different then noise if they even appear at all. This is actually a good thing because it allows the camera to see detail on the surface, like the differences between the astronaut and a rock. If the exposure was much longer, then everything would just look white, as if the camera was taking a picture of the sun through a mirror.
Which is actually pretty cool to think about. The sun is so bright it practically turns rock into a mirror.
the shuttle is also moving, and they launch the lander on a path such that (hopefully) the relative velocity of them is close enough to zero by the time they intersect that they can dock with a few manipulations...
>practically turns rock into a mirror
which reflects about 10% of the light
There's no atmosphere on the moon to refract the sunlight and obscure the sky, so daytime means nothing if the sun is not in your field of view, at least that's my non-expert understanding.
The reason for no stars is because in order to expose the relatively bright foreground (moon surface, astronauts) the exposure settings for the camera are not long/open enough to capture the light from the much feinter stars.
You can emulate this by going outside on a starry night and taking a picture of someone with the flash on (the flash would emulate the bright sunlight shining on the moon's surface). You won't see any stars in those photos.
Keep in mind they had a speech prepared for the news of their loss if they missed well before they even landed on the moon.
It's not actually made of tinfoil. It looks like it is, but that's because it's *covered* in tinfoil (for temperature control reasons), but made of perfectly decent structural materials.
It could lift off from the Moon, despite being far smaller and less sturdy than an Earth ascent rocket, because:
>1. No atmosphere to get in the way, and thus no need to account for the rigors of atmospheric ascent at high velocity, or to add extra thrust to deal with drag.
>2. Dramatically lower gravity, thereby meaning you need much less thrust, and so your ship doesn't need to be anywhere near as sturdy.
>3. A much shallower gravity well, meaning much lower delta-V is needed. Because the rocket equation (the equation governing the amount of rocket you need to transfer some amount of payload) is exponential, this causes a radical reduction in the amount of fuel needed compared to going from Earth to Earth orbit. For instance, a given rocket engine might take 9 tons of propellant to lift 1 ton of payload to Earth orbit, but only 0.6 tons of propellant to lift that same payload off the Moon to Lunar orbit.
>and fly back to Earth
It didn't. The actual flying-back-to-Earth parts of the spacecraft were left orbiting the Moon (with poor forgotten Michael Collins aboard) while the landing-on-the-Moon part** was detached and landed. After it lifted off again, they reattached it.
*The Command/Service module
**The Lunar Excursion Module
One for the Moon and one for the Studio.
>Flimsy looking. Like a soda can.
One of my lecturers back at university was working on the space race projects. he told us stories that you never hear in the flag waving shows or glossy books. He put it plainly that it was like rubber bands and chewing gum that held things in place and it sure was flimsy looking. There was simply not any margin for extra sturdiness or margins.
It was a cold war space race against the Soviet Union. It was victory or death. And they made quite a few contingency plans in case of death. In hindsight it is amazing things went as well as they did but it was a different era. It was in the same era that they got the Blackbird operational in five years.
Then something happened, not sure what. Space became the domain of career bureaucrats with no goals other than their own career and thus got the Space Shuttle with all the problems that brought. It is also a sign of our time that F-35 is not yet really operational.
As I said, the space race was a long, long time ago.
Newtonian physics was the ONLY physics in Kelvin's time. Everything under physics was covered by Newtonian physics. It really doesn't seem so unreasonable that we will someday develop a new branch of physics that's radically different from our current understanding, just like relativity was compared to the old Newtonian model of physics.
They hung what was basically tin foil on it. This is common for thermal management in space. There's no wind to blow it off, and small holes don't cause a problem, so it's not like they need a durable outermost surface.
That tells you nothing about how it was built underneath. You could hang tin foil on foot-thick armor plating if you want.
However, it was very lightly built and fragile. The forces involved in landing and return to orbit are small. Lunar gravity is only about one sixth what we have on Earth, so the accelerations needed to land on and launch from the moon are similarly small.
The astronauts had to be careful with the lander, because they could basically have torn it apart by hand if they wanted. While they were being made, minor incidents like dropped tools caused serious damage.
I love space and literally never heard of this guy, what a fucking looser.
The Blackbird leveraged many decades of aviation knowledge, and it took 5 years. The Apollo program took only 8, and had far less robust tech and knowhow to leverage, plus had the challenge of the unknowns of operating in space and the moon. I don't think you can compare the two, the Apollo mission was a monumentally greater challenge.
>The Blackbird leveraged many decades of aviation knowledge
How many decades of titanium clad aerospace structures were you aware of? Considering the plot to just get the material it cannot be many.
Anyway Apollo was based on Mercury and Gemini which were based on German technology from the 1930's.
My experience form industry, including aerospace industry is that the beancounters now call the shots. Not so back then, and that is the ear my lecturer told us about. That time they needed, absolutely needed, the results and engineers and scientists were i charge of getting those results.
Then came the rot. Technical guys warned about launching Challenger. Bean counters said "go!". And 7 astronauts were killed. Normally this would be regarded as murder. None were ever investigated. None will ever face trial.