Flase wrote:The only thing that doesn't look right to me is how small the Lunar lander was. With a little puff of flame, it was able to reach the Moon's escape velocity, whereas craft that takeoff from Earth require huge whopping booster rockets...
Chris Peterson wrote:
That said, the thrust of the lander motor was higher than it appears in images. Rockets don't normally produce much visible output, unless they are in the atmosphere. So the Saturn boosters appear more powerful than they actually are, and the lander boosters appear less so. (Not that the Saturn motors weren't vastly more powerful... after all, the fuel laden Saturn with its payload massed nearly 3 million kg, compared with the lunar module ascent stage mass of less than 5000 kg, and the latter with no atmospheric drag and 1/6 the surface gravity.)
7.91 km/s : Earth Orbital velocity
1.68 km/s : Lunar Orbital velocity
................................................
Exhaust gas velocity Ve for rocket engines:
2.9 to 4.5 km/s : liquid bipropellants
2.1 to 3.2 km/s : solid propellants
1.7 to 2.9 km/s : liquid monopropellantsAnn wrote:One of the best arguments that I've ever heard against the claim that the Moon landings were a hoax is that this happened during the height of the Cold War. After all, the Moon landings were just as much about the United States beating the Soviet Union as it was about exploring the Moon...
Chris Peterson wrote:Ann wrote:One of the best arguments that I've ever heard against the claim that the Moon landings were a hoax is that this happened during the height of the Cold War. After all, the Moon landings were just as much about the United States beating the Soviet Union as it was about exploring the Moon...
I've always thought that was a good argument, as well, although hoaxers make a (very weak) case for mutual support of fake space programs.
There's a really good technical demonstration that the landings were real- one which is completely devastating to any suggestion that the imagery was faked. We can see in the movies that the astronauts are operating in a vacuum. How can we tell? By the way the dust flies when they walk, or when the rovers move. Dust in even thin air is very non-ballistic in its motion. With its very low mass, its behavior is dominated by aerodynamic effects, not gravity. Toss a little dust in the air, and you get a cloud that floats off. But the Apollo films show something very different (I love using them in the classroom, because everybody instantly recognizes that something looks "wrong", but it can take a while before anybody figures out what that is)- the dust moves in beautiful little parabolic arcs, purely ballistic. Certainly, no CGI capability existed back then to fake that, so it could only be done in a vacuum. The suggestion that everything was filmed in massive vacuum chambers just adds to the absurdity of hoaxers claims (especially since the same people often suggest the flags are blowing in the wind).
Dreadmon wrote:Odd that you don't see the rover's tracks in the picture.
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