Help wanted: materials for planet display

[ngc3314]

I have landed with a task, part of which I am clueless about starting (and so are the colleagues I've checked with). BAUTers embody a seemingly limitless fund of arcane knowledge, so here goes...

Our institution has developed a set of exchange programs with Cuban institutions, all carefully operated to stay on the legal side of US trade restrictions. I am supporting a project to build a new planetarium and science-outreach center as part of a broad renovation of Old Havana. They have the Goto projector, which goes in a 12-meter sphere. The outside of this sphere is to be textured and painted to look like the Sun under UV illumination. They would like to hang scale-sized planets in the hall arranged out from the Sun, likewise textured and painted. So the question is - what could these be surfaced and painted with to give plausibly planet-like appearances? I'm hoping to talk them into at least having the UV illumination vaguely near the Sun so as to light up one hemisphere each. The directors of planetaria in New York and LA have mostly responded "hmmm". At this scale, Jupiter has an equatorial diameter of 1.2 meters, and the Earth would have 11 cm (Mercury will be some very tedious detailing).

Help me, Obi-BAUT, you're my only hope...

[Neverfly]

They would like to hang scale-sized planets in the hall arranged out from the Sun, likewise textured and painted.
Must be a very long hall!!
Unless the to scale planets are very tiny.
So the question is - what could these be surfaced and painted with to give plausibly planet-like appearances? I'm hoping to talk them into at least having the UV illumination vaguely near the Sun so as to light up one hemisphere each. The directors of planetaria in New York and LA have mostly responded "hmmm". At this scale, Jupiter has an equatorial diameter of 1.2 meters, and the Earth would have 11 cm (Mercury will be some very tedious detailing).

Help me, Obi-BAUT, you're my only hope...
What do you mean by planet like?
At those sizes, any planet would appear to be smooth. Even if they show craters, the texturing of them would be almost imperceptible to the touch at that size.
I would have them printed with actual imagery.

For the gas giants- which would be the most visible- smooth is best. In fact, you couldn't get it smooth enough!
The small rocky ones will be more so, but also have thicker atmospheres- a smooth look is good. At that scale, the Earth, with all its canyons and ridges and mountains would still be about as smooth as a billiard ball to the touch.

[ngc3314]

Must be a very long hall!!
Unless the to scale planets are very tiny.

What do you mean by planet like?
At those sizes, any planet would appear to be smooth. Even if they show craters, the texturing of them would be almost imperceptible to the touch at that size.
I would have them printed with actual imagery.

Oops, I needed to be more specific - the idea is for the planets to be to scale with the Sun ball in size, but not in location. They plan a separate outdoor display for that (where the planets will indeed be too small for details, not to mention out in the tropical weather).

They'll be hanging out of touch, so the texturing matters only for overall visual feel and, perhaps, ease of applying colors. Any hints on how to print such things with imagery? I liked that idea, but trade restrictions mean that it's much more difficult if we have to take anything much bigger than will fit in hand luggage. Unless there are companies in Canada or Mexico that would give them a good deal...

[Neverfly]

Oops, I needed to be more specific - the idea is for the planets to be to scale with the Sun ball in size, but not in location. They plan a separate outdoor display for that (where the planets will indeed be too small for details, not to mention out in the tropical weather).

They'll be hanging out of touch, so the texturing matters only for overall visual feel and, perhaps, ease of applying colors. Any hints on how to print such things with imagery? I liked that idea, but trade restrictions mean that it's much more difficult if we have to take anything much bigger than will fit in hand luggage. Unless there are companies in Canada or Mexico that would give them a good deal...

Beats me.http://us.i1.yimg.com/us.yimg.com/i/mesg/emoticons7/106.gif

I've seen balls printed seamlessly. I don't know how it was done.

My son lodged a ball in a printer once. The printer went on strike though.

I've seen some laminated in strips- but that isn't perfectly seamless.
You might do a search on printing companies and ask a few of them how they print balls. But be clear in your wording on that question.
They might get the wrong idea...:whistle:

By packing in a suitcase- you do mean the materials needed right?
I have this image in my mind of you- like Atlas- supporting Jupiter on your back at the airport...

[Spacewriter]

Hi, you have to worry about lighting, too. Contact me offline -- I work with museums and exhibits and might be able to point you to some useful resources. It's not as straightforward as you might think -- which is probably why the folks in LA and NY were kind of "meh" about it...

C

[Jeff Root]

My first concerns about the surface material are: 1) Will it show dust
excessively? 2) Can it be easily cleaned without being damaged?

If I were doing it, I might make Mercury a mottled gray powder-coated
steel ball mounted on a very short steel rod (just long enough to raise it
slightly off the support base), then put it on a wall or pedestal. If it is
hanging from the ceiling, it will be too far away to see any detail at all.
Unless it is very carefully lit, it could be too far away to see, period!

Here's a link to an example of a powder-coated steel product found in a
quick Google search:
powder-coated steel trash bin (http://hanware.manufacturer.globalsources.com/si/6008801109243/pdtl/Trash-bin/1003799391/Trash-Bin.htm)

How will you transport Jupiter, and Saturn with its rings, in a suitcase?

Will the planets have moons? The moons of the planets in the Solar System
happen to be pretty easy to categorize as "large", "medium", and "small".
Luna, Io, Europa, Ganeymede, Callisto, Titan, and Triton are the large ones.
Saturn has four medium-size moons, Uranus has five, and Pluto has one.
The Sun and Planets to Scale (http://www.freemars.org/jeff/planets/planets5.htm)

Even the largest asteroid in the main belt (Ceres) is in the "small" category.

-- Jeff, in Minneapolis

[01101001]

By packing in a suitcase- you do mean the materials needed right?
I have this image in my mind of you- like Atlas- supporting Jupiter on your back at the airport...

Inflatables? Like 1-world globes (http://www.1worldglobes.com/planetmodels.htm)? Too bad they only seem to do Moon and Mars (and don't do the scales needed). That picture of the guy holding the 10-foot Mars on his back is cool though.