Hi all. I've been a big fan and supporter of Cartes du Ciel before most even 
knew about it (I even compiled the very first Tycho catalogs for it! :) (now 
obsolete :( )

But I have a fun project I'm trying to do. I recently bought a fun toy called 
an "Astrostar" planetarium projector from ebay. Sold by a lot of folks in 
China. A little searching on ebay by that name and you can get one with 
delivery for under US$10. They're really nice for that price. And if you 
substitute a little MagLight halogen bulb for them (those teeny-tiny 
grain-of-wheat lamps), you can get really nice pin-points of stars projected 
all over your room.

BUT ... there's a problem with these Astrostar toys. I found that the panels to 
create the dodecahedron star-projection slides do NOT represent the true sky. 
They are just thousands of random dots. Some of the sellers show true 
constellations on the photos' walls in their ads, but when I wrote to them 
asking about it they all confirmed that they just project random dots. I 
couldn't find any sellers that sold ones with true night-sky patterns. So I 
thought ... Cartes du Ciel to the rescue! I could print up new panels on 
transparency material using the highest resolution of my photo-quality printer. 
Then assemble a new projection dome from those.

So ... is there any easy way to divvy-up the sky into the required panels? The 
south face of the dodecahedron is taken up by the base of the simple 
"projector", so only 11 of the 12 dodecahedron panels are needed. I found too 
that if I zoom out far enough for one side of a dodecahedron that many areas of 
the sky don't get filled in with stars from the Tycho 2 catalog. A display 
limit I think (computer RAM related?) The empty areas get filled in again when 
I zoom in.

It would be great if there were some simple script of something where it would 
take a star display up to magnitude of 9 or so and spit it out into the 
required pentagon shapes for printing. I could then even include subtle colored 
lines for the constellations and all too.

This little and inexpensive "Astrostar" toy would be really nice with the true 
sky projected with the accuracy, lines, colors, and shadings of Cartes du 
Ciel's display.

Can anyone help?


Think too of all those kids that might have bought these star-projector toys. 
If they knew of a program that could create the true sky for them, improving 
it, even printing labels on objects, it would get Cartes du Ciel into a lot of 
new hands and minds and get them learning! Maybe in the future there could be a 
menu option in Cartes du Ciel for printing things like this, and a simpler 
cylinder for an equatorial projection, or planispheres too.



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