Re: 40 Years Ago Was it a Hoax?
I have a couple of questions to which I have not found answers
1) Lunar module landed and was slowed down by rockets firing to cushoin the fall. This would surely have blown away all dust for miles (No atmosphere / resistance to stop it)
Yes, the LEM used a rocket engine to slow the decent but the engine wasn't used at a high thrust and the effects of that thrust are greatly diminished.
Why? The moon on has 1/6th the Earth's gravity and the weight of the LEM in the presence of the moon is only around 3500-4000 lbs. The decent engine could produce 10,000 lbs of thrust but only a fraction of that was used on decent.
Therefore, using only a bit more than 3500 lbs of thrust would allow Neil Armstrong to keep the LEM at a constant altitude. A gentle decent would probably be around 3000 lbs of thrust. That sounds like a lot but you've got to remember that the thrust is directed with a nozzle with a diameter of around 55 inches and that nozzle is designed to spread the thrust out over a wide area.
Convert that nozzle diameter to square inches with A = pi * r^2 and you'll get around 2374 sq inches. Take the 3000 lbs of thrust over that area and you only get around 1.25 psi, 1.25 pounds per square inch of force. That isn't a whole lot. Now this isn't entirely perfect because the nozzle isn't perfect at distributing thrust 100% uniformly over the nozzle area. I'm sure a radial function exists developed by the rocket guys that describes the thrust distribution but you get the idea.
It'll move some dust, as evidenced in the various photos and videos of the landings site and blast area. But it isn't going to blow out of an area for miles, or even tens of yards. Check out some of the footage and pictures, you'll see blown dust but nothing like what you're thinking. The dust gets blown in a straight line and continues "out of sight over the horizon", Neil Armstrong's words. So, no billowing clouds.
2) Armstrong coming down the stairs and stepping onto the moon Who took that photo? Someone would have to be on the surface at reasonable distance from the module to get that shot.
The camera on the LEM took the picture. You can read about deployment of the camera here. The LEM is actually a pretty big piece of flying machine with a gear span over 30 feet. The camera taking the picture folds out and is probably 20 ft from the ladder. Neato design, had a plastic model when I was a kid that incorporated that feature as well as the folding legs and the pop out rover.
Apollo 11 - Wikipedia, the free encyclopedia
The important part is here and if you wish to visit the Smithsonian Air and Space museum you can have a look at a LEM and see the camera package and how it folds into the module.
At 02:39
UTC on Monday July 21 (10:39pm
EDT, Sunday July 20), 1969, Armstrong opened the hatch, and at 02:51
UTC began his descent to the Moon's surface. The Remote Control Unit controls on his chest kept him from seeing his feet. Climbing down the nine-rung ladder, Armstrong pulled a D-ring to deploy the Modular Equipment Stowage Assembly (MESA) folded against
Eagle's side and activate the TV camera, and at 02:56
UTCEDT) he set his left foot on the surface.<sup id="cite_ref-ALSJ_4_19-0" class="reference">
[20]</sup> The first landing used
slow-scan television incompatible with commercial TV, so it was displayed on a special monitor and a conventional TV camera viewed this monitor, significantly reducing the quality of the picture.<sup id="cite_ref-Blunder_5_20-0" class="reference">
[21]</sup> The signal was received at
Goldstone in the USA but with better fidelity by
Honeysuckle Creek Tracking Station in Australia. Minutes later the feed was switched to the more sensitive
Parkes radio telescope in Australia. Despite some technical and weather difficulties, ghostly black and white images of the first lunar EVA were received and broadcast to at least 600 million people on Earth.<sup id="cite_ref-Parkes_21-0" class="reference">
[22]</sup> Although copies of this video in broadcast format were saved and are widely available,
recordings of the original slow scan source transmission from the moon were accidentally destroyed during routine magnetic tape re-use at NASA. Archived copies of the footage were eventually located in Perth, Australia, which was one of the sites that originally received the Moon broadcast.
