If you’ve driven down US Highway 101 in the Silicon Valley and puzzled over the existence of an enormous hangar about a half-mile from the road, then you’ve seen NASA Ames. Measuring 200 ft high x 300 ft wide x 1,100 ft long, Hangar One, as it’s known, can fit six football fields inside. These days, its skin has been stripped off because it contained PCBs, asbestos, and lead paint. The agency is keeping its steel-trussed interior structure as a landmark. (Source: Design News)
I'm pretty sure the mission referred to is the Lunar Orbiter missions, which made 500+ orbits of the moon per mission, with hi-res cameras. The images were recovered from telemetry tapes and digitally restored in 2009-2011. Here's a link to the Wikipedia article on the effort:
The telemetry had four times the dynamic range of the film copies captured in the pre-Apollo era and used for the landing site selections.
The Surveyor missions were soft-landing missions that proved (beyond the Russian Luna efforts) that craft wouldn't disappear in a fall of moondust. They had 600-line video cameras, but the imagery was of the sites around each landing.
Air temperature will drop as it accelerates through the test section, then heat back up as it declerates. But it's not a 100% recovery. Waste heat from the fan motors will increase the air temperature too. Just my speculation, but the air temperature would probably increase as it recirculates. Air temperature is a critical variable in aerodymamic testing...so an open loop is probably a lot more controlled, though that depends on the outside weather.
The secrecy is nothing new. The reason the Surveyor data tapes were not recovered sooner is that the Surveyor spacecraft were essentially repurposed spy satellites. Because we were in the cold war then, the agency went to great lengths to make sure the real performance capabilities would not be known by anyone except who had a need to know. All the images that have been in the public domain until now were intentionally downrezzed. It took quite a bit of effort to figure out how the data was encoded on those tapes, as that system was highly classified at the time. A demodulator had to be built from scratch, as no demodulator for that format existed. They did figure it out, and people's jaws literaly dropped when they saw the first images recovered off the tapes. This project is being done with private money, and the tape machines were found in someone's garage. The machines required a stem-to-stern rebuild before they would safely handle tape.
I actually saw one of those Surveyor spacecraft many years ago, at the Eastman museum in Rochester, NY. It was the flight spare, and was in storage in the museum's apparatus vaults. I am told that the Smithsonian now has this spacecraft, and it is now on display at the Air and Space museum on the Washington mall.
Not sure when NASA went stealth. During the sixties, NASA was everywhere in the press. It was a concerted effort that seemed to be government wide. The astronauts were household names. Stories about the technology were everywhere.
Anyone posit a clue why they didn't make the wind tunnel a closed loop ? Seems they are wasting a lot of energy taking ambient air up to test speed, then just dumping it. Would seem a lot more efficient (not to mention quieter for their neighbors) to close the loop, so the air going back for a second loop would still be moving at 10-15mph.
To be honest Rob, I have no good explanation. I greatly fear it is soley beauracratic thinking. I am not asking for an open door to any NASA facility, but NASA has gone too far the other way. Picture IDs for a simple tour, of a place that doesn't even have launch facilities? Unjustified.
The structure is truly gigantic, far911. It was one of a several sites at Ames that were overwhelming in their size. The 80' x 120' wind tunnel was another. And, yes, I saw the Area 51 stories recently -- although it didn't involve any extraterrestrial life. It's worth noting that one of our NASA experts in the supercomputing division did tell us that he expects us to find life somewhere in the galaxy "during our lifetime."
Theortetically speaking, TJ, any citizen can show up at NASA Ames and see some of the memorabilia. But the only things they can really see are in a tent near the gate. We were repeatedly warned on our tour, "Don't forget your picture IDs." We also had to pass through security on the way in, almost as if we were entering a foreign country. The security there is serious.
Earlier this year paralyzed IndyCar drive Sam Schmidt did the seemingly impossible -- opening the qualifying rounds at Indy by driving a modified Corvette C7 Stingray around the Indianapolis Motor Speedway.
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