A Question Regarding The Dark Side Of The Moon.

[BK613]

Not that I have any hope that it will illuminate where it is needed but:

From the Oxford English dictionary:

Dark
1.1 Hidden from knowledge; mysterious: a dark secret
Synonyms
mysterious, secret, hidden, concealed, veiled, covert, clandestine;
enigmatic, arcane, esoteric, obscure, abstruse, impenetrable, incomprehensible, cryptic

Prior to the advent of spaceflight, the far side of the Moon was unknown, hidden from view because tidal locking keeps only one side facing the Earth. Thus it was the dark side of the Moon. The phrase never had anything to do with light and shadow, but what was known and unknown.

A thread quoting Pink Floyd is always a win, though.

 

[Gov Kodos]

Cat-Women of the Moon taught me cigarettes will ignite when exposed to the light side.

 

[YellowSubmarine]

I think I have a solution. Put the telescope on wheels and make it run around the moon with 5 m/s. Sure, the stars will wobble in its view from the imperfections in its track, it will run out of energy in the dark before it falls into a crater, but it will be on the dark side of the moon.

 

[The Old Mixer]

It syncs up bettter with The Wizard of Oz if you're stoned.

Wait, that wasn't the question?

 

[Asbo Zaprudder]

Syncs up with just about anything if your're stoned.

 

[publiusr]

So then your only question would be WHY you'd want to put one on the moon. It would have to give you some advantage over a space-based one. I've heard some proposals wanting to put radio telescopes on the far side of the moon to shield it from Earthly transmissions, but that doesn't need any blocking from the sun.

If something is on a stable but airless surface, you can do work more easily--you don't have as much gravity as here on Earth--but you can bear down, put hammers "down" and not have to go flying off into space. Buried things also stayy buried: http://forum.nasaspaceflight.com/index.php?topic=39575.0

Imagine you are doing work as an astronaut. You have two choices--float like Storey Musgrave and sweat and fight in zero g--or just walk to work with a tool box that won't float off. If something is stuck--get a lead hammer and give it a good lick.

Yes, space based assets can slew in more directions--but sometimes, mass/weight is your friend.

Even a "free-floating" telescope can benefit from a little added mass.
http://www.wired.com/2015/02/strategic-defense-military-uses-moon-asteroid-resources-1983/

After armor, the most important application of space resources in terms of mass was what the La Jolla workshop report dubbed “stabilizing inertia.”

It may not take much to harvest
https://updatesfromthenightshift.files.wordpress.com/2015/07/wgoy3qt.png
http://arxiv.org/pdf/1501.03193v1.pdf
http://arxiv.org/ftp/arxiv/papers/1304/1304.5082.pdf

But I digress

 

[Crazy Eddie]

So then your only question would be WHY you'd want to put one on the moon. It would have to give you some advantage over a space-based one. I've heard some proposals wanting to put radio telescopes on the far side of the moon to shield it from Earthly transmissions, but that doesn't need any blocking from the sun.

My idea once was for a gigantic reflecting mirror the size of football stadium built into a lunar crater. Something like the Aricebo Observatory, except as an optical instead of radio telescope. Build it at the top of a raised structure significantly above the lunar surface and possibly with electrostatic grids on the side to eliminate dust contamination.

This structure would be a lot easier to build and manage on a fixed lunar surface than as an orbiting platform, especially if it has a sizeable staff. Similarly, a multi-telescope setup -- the optical equivalent of the Very Large Array -- could work this way as well, since all of the telescopes could be in a fixed orientation and their cameras could be multiplexed to create a virtual aperture.

Building on the far side of the moon makes sense if you want your telescope to be large enough that shielding from Earth and Sunlight won't be cost prohibitive. But if you don't care about that sort of thing or if you have a really efficient way of blocking the glare, it could be just about anywhere on the surface.

 

[sojourner]

With 1/6th gravity and no weather to worry about. Large light shields made of mylar should be doable.

 

[publiusr]

My idea once was for a gigantic reflecting mirror the size of football stadium built into a lunar crater. Something like the Arecibo Observatory, except as an optical instead of radio telescope.

Any reason it can't be both? Arecibo doesn't have a solid, very shiny surface.

A full spectrum can be gained.

 

[Asbo Zaprudder]

There is the problem of dust contamination for mirrors.
https://en.wikipedia.org/wiki/Lunar_soil#Moon_dust_fountains_and_electrostatic_levitation
Lunar dust is apparently pretty abrasive to machinery as well as being potentially harmful to health.
https://en.wikipedia.org/wiki/Lunar_soil#Harmful_effects_of_lunar_dust
https://en.wikipedia.org/wiki/Adverse_health_effects_from_lunar_dust_exposure

 

[StarCruiser]

The Dark Side of the Moon?

It's a very good Pink Floyd album - I highly recommend it...oh, we're talking about "THE MOON"...nevermind...

 

[publiusr]

There is the problem of dust contamination for mirrors.
https://en.wikipedia.org/wiki/Lunar_soil#Moon_dust_fountains_and_electrostatic_levitation
Lunar dust is apparently pretty abrasive to machinery as well as being potentially harmful to health.
https://en.wikipedia.org/wiki/Lunar_soil#Harmful_effects_of_lunar_dust
https://en.wikipedia.org/wiki/Adverse_health_effects_from_lunar_dust_exposure

I think an elecrical charge might take care of the dust, but that might cause interference.

Housing over a crater in a dome allows a shirtsleeve environment inside, where radiators can work--and the dome takes all the dsut--with maybe a half-circle shaped wiper going over the top.

 

[Gingerbread Demon]

Speaking of music

http://www.huffingtonpost.com.au/en...us_56c80662e4b0928f5a6c0679?section=australia

 

[Asbo Zaprudder]

EM radiation from the Sun and Jupiter and/or ionization from cosmic rays hitting the electronics? Cosmic rays were judges to be the likely cause of the light flashes also reported by Apollo astronauts.

https://en.wikipedia.org/wiki/Cosmic_ray_visual_phenomena

 

[publiusr]

This is why the Orion spacecraft has hardy electronics.
http://www.airspacemag.com/space/americas-next-spaceship-180952126/?page=2

Yes there will be a more modern look--as inspired by Okuda

A key moment in sci-fi film history, described by designers Nathan Shedroff and Christopher Noessel in their book Make It So: Interaction Design Lessons from Science Fiction, may have had an influence on the look of future spacecraft (and consumer electronics).


In terms of switches:
Lee Morin, wearing a blue jumpsuit with a “Mach 25” badge, tells me that the shuttle cockpit had 1,249 switches. “There were approximately 2,000 for the whole vehicle,” he says.

Now in some ways, the electronics of the late 1970s might well have hit a sweet spot. Not as primitive as Apollo--or as sensitive as today's electronics. A wiring harness and rope memory can slide past each other--where that same vibration or flexing might pop a chip loose.

 

[Gingerbread Demon]

Actually apollo spacecraft used core memory which is bloody fascinating. I love looking at those devices.