I just beat The second Ripley on the Pirate homeworld.  I am really trying to get all the items before going to finish the game.  I have done everything that I can at the Chozo Observatory for unlocking item locations, but there are so many spots still sitting there that are not lit up and I can do nothing with.  Does anyone know how to get those extra bomb slots lit up to send some more satelites up? 

I don't think you have to do anything with those slots. You only need to activate the ones that were already lit up, if I remember correctly.

 Correct, you can only use the lit bomb slots.

 You can get satellite data for the pirate homeworld by using your X-ray visor and nova beam on that phazite panel at the base of the holographic projector. It opens a door to the column supporting the holographic project and you're one hand scan away from the location of all pirate homeworld powerups.

 The only place you cannot get satellite data for is  the Valhalla, so if you've turned all the little white dots into Xs elsewhere, you need to search the Valhalla more thoroughly.

What could these extra slots be?  Do you think that they could be downloadable content in the future?  It is just weird how they are there, but serve no purpose.  You would think that they would not even bother putting the spider ball track to them if that was the case.

 That room's purpose is to explore the galaxy, and it's a big galaxy.

 Samus' purpose, however, only concerns a few planets in that galaxy, so she doesn't need to scan every star within 100 light years.

 The lit bomb slots are what Samus is looking for. The unlit ones are everything else the Chozo were doing with it.

^^^(EDIT: really at 2 posts up) its called atmosphere. By providing a track to broken/off line bomb slots it gives the feeling of the room being run down and unmaintained. I doubt there is any downloadable content, as Nintendo doesn't do that (yet anyways)

DLC is possible (I even made a thread about a Wii game from TGS that plans to use it, but it looks like not many people cared) but in this case hose extra bomb slots are simply for effect as others have said.

I guess it makes sense, but it is weird that they would have spiderball track leading up to everyone that is of no use to Samus.  If they were of no use to her, then why put Spiderball tracks to them?