Fascinating story of recovered pre Apollo Lunar images....

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MeteorWayne

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Fascinating story of recovered pre Apollo Lunar images....

http://www.latimes.com/news/nationworld ... 1431.story

"Rising over the battered surface of the moon, Earth loomed in a shimmering arc covered in a swirling skin of clouds.

The image, taken in 1966 by NASA's robotic probe Lunar Orbiter 1, presented a stunning juxtaposition of planet and moon that no earthling had ever seen before.

It was dubbed the Picture of the Century. "The most beautiful thing I'd ever seen," remembered Keith Cowing, who saw it as an 11-year-old and credited it with eventually luring him to work for NASA.

But in the mad rush of discovery, even the breathtaking can get mislaid.

NASA was so preoccupied with getting an astronaut to the moon ahead of the Soviets that little attention was paid to the mountains of scientific data that flowed back to Earth from its early space missions. The data, stored on miles of fragile tapes, grew into mountains that were packed up and sent to a government warehouse with crates of other stuff.


And so they eventually came to the attention of Nancy Evans, a no-nonsense woman with flaming red hair that fit her sometimes-impatient nature. She had been trained as a biologist, but within the sprawling space agency she had found her niche as an archivist."

It's a great read... I hope this image comes out- MW

lat-lunarmo_kgruuhnc20090322044631,0,1706172.photo
 
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earth_bound_misfit

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petet":m2py3oed said:
Great story, thanks!

Indeed it was. Thanks Wayne!
Makes me wonder what other gems of Space history have be lost to the dump.
 
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astronaut23

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Theres no way that second picture is original. Thats looks like a digital image like that probe that used rader to see through the clouds on venus. Thats too low to be in orbit. What is it coming in for a landing?

The first one shows that you can take pictures like the one on Apollo 8 unmanned.
 
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MeteorWayne

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astronaut23":i35t58k2 said:
Theres no way that second picture is original. Thats looks like a digital image like that probe that used rader to see through the clouds on venus. Thats too low to be in orbit. What is it coming in for a landing?

The first one shows that you can take pictures like the one on Apollo 8 unmanned.

I see astronomy, physics and photography are not your strong suits...
 
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abq_farside

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MeteorWayne":fngmjj83 said:
astronaut23":fngmjj83 said:
Theres no way that second picture is original. Thats looks like a digital image like that probe that used rader to see through the clouds on venus. Thats too low to be in orbit. What is it coming in for a landing?

The first one shows that you can take pictures like the one on Apollo 8 unmanned.

I see astronomy, physics and photography are not your strong suits...

And if you would have read the story, you would have noticed the line:

"Unlike the picture that the public had seen, this version had twice the resolution and four times the dynamic range."

Great story - thanks for posting it.

Edit: formating
 
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astronaut23

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That probe is not taking a picture looking straight down on the mountains. Its taking a picture from the side. If its even a real image and not computer generated. It looks like a computer generated image. Like something you'd see playing Orbiter spaceflight sim.
 
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MeteorWayne

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astronaut23":1s7iq9l2 said:
That probe is not taking a picture looking straight down on the mountains. Its taking a picture from the side. If its even a real image and not computer generated. It looks like a computer generated image. Like something you'd see playing Orbiter spaceflight sim.

So what's your point? Are you saying you can only take images looking straight down? At that point it was about 40 km (25 miles) above the lunar surface. Just because it looks computer generated to you does not mean that it is. Where do you think computer gererated images figure out what they should look like?
 
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astronaut23

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25 miles is pretty low orbit. How close can you orbit the moon and be in a stable orbit? I assume pretty close compared to Earth cause theres no atmosphere to slow you down.
 
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CalliArcale

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Whoa. That image of Copernicus crater is AWESOME.

Yeah, that really is what craters look like if you view them from the side. Less useful for most scientific purposes, but absofreakinlutely beautiful.

astronaut23 -- that is definitely not a digital image. It's analog. The underlying technology is revealed by the horizontal lines across it. I don't think I know enough about the technology (vidicon tubes, IIRC) to do a decent job of explaining it without confusing folks, so I won't try. But you can see the same effect in a lot of other deep space photography of the period -- and even pictures of Earth taken from orbit.

Regarding the altitude, the spacecraft was indeed probably not all that high. You can orbit the Moon much more closely than you can orbit the Earth, because you don't have to worry about atmospheric drag.

Also, that crater is quite a bit bigger than you might think. It's 93 km across, so it's actually not all that close to the orbiter if that much of it is clear in the picture. Those little bumps on the crater floor are actually mountains over 1.2 km tall.
 
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MeteorWayne

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Well, it didn't need to be a stable orbit since the mission had a finite lifetime; in fact it was ended early (spacecraft crashed onto surface intentionally) due to low fuel and to prevent interference with Lunar Orbiter 2. IIRC, the apolune (furthest point of orbit) was over 1000 km, the 40 km was the low point of the orbit.

Because of the mass distribution on the moon, very low orbits are not stable, but I don't know the exact answer to your question. I'll see what I can dig up.
 
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drwayne

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astronaut23":29deiuzr said:
25 miles is pretty low orbit. How close can you orbit the moon and be in a stable orbit? I assume pretty close compared to Earth cause theres no atmosphere to slow you down.

There is no drag, so one would think that lunar orbits are very stable.

There is another factor however. The lunar mass is not uniformly distributed, with concentrations of mass
leading to orbits that move about and eventually decay. You might find this interesting:

http://science.nasa.gov/headlines/y2006 ... worbit.htm

Wayne
 
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CalliArcale

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astronaut23":2tped6th said:
25 miles is pretty low orbit. How close can you orbit the moon and be in a stable orbit? I assume pretty close compared to Earth cause theres no atmosphere to slow you down.

You'd be better off a bit higher, for a variety of reasons. Lunar Orbiter 1's orbit was certainly achievable, but not ideal. For one thing, it wasn't 25 miles all the way around. Lunar Orbiter 1 had a highly eccentric orbit -- periapsis 25 miles, apoapsis (most distant point) about 1,160 miles. This is not at all ideal for mapping. Most lunar orbiters nowdays go into nearly circular orbits at very high inclination (polar orbits) so they get a consistent altitude, aren't too influenced by unevenness in the Moon's gravitational field, and can stick around for a while without thruster burns. 100 km seems to be fairly typical nowdays. (That's way low for an Earth orbit, but fine for the Moon.)

But Lunar Orbiter 1 wasn't intended to map the Moon. The objective was to a) get *something* into orbit (gotta try and beat the Soviets, after all), and b) get pictures as close as possible without actually smacking into the thing. The highly eccentric orbit was good for that, because periapsis took it very close indeed. Previously, the best images had all come from the Ranger spacecraft, which transmitted images as quickly as they could before slamming into the Moon at high velocity. Lunar Orbiter 1 could get images from as close as 25 miles but take more time with the images, allowing better quality, because it would get more opportunities later.

Heh; I see MW already answered you, but I'll still post this answer. ;-)
 
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astronaut23

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Wow, 1000 by 40. Sounds like my orbits when trying to launch manualy in orbiter sim. I launched the Buran manually and was like a "normal orbit" of 250 miles on one side of the Earth but headed out like thousands of miles on the other side. :lol:
 
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MeteorWayne

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The final orbit for MESSENGER around Mercury will also remain very eccentric. I don't have the numbers handy, I'm sure Andrew does....
 
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