I just finished my third playthrough of ME2, and this time I played as a real asshole whereas the first two times I was positively angelic. After beating the game the first two times, the roiling planetoid thing behind the Illusive Man turned the white/blue color and I assumed that's just how it is. This time, with my asshole character, the planetoid turned red. I wonder if that's related to paragon/renegade, or the fact that the angel destroyed the human reaper and the asshole decided to keep it.  
 
It's also kind of interesting how the object is sort of fighting with itself between blue and red during the game and then settles into one after it's over.
 
Curious to see how this impacts ME3! What are the theories as to what that thing is or means? I searched on here but didn't see anything.

I suspect it's nothing more than cosmetic choices based on your decisions and moral meter given the colours as you mentioned do reflect the two sides of the bar. Blue white for paragon and red for renegade as an ultimate visual accomplishment of where you stand. 

I always wondered whether he had that because he was interested in the star that Tali was investigating, supposedly it's growing larger than normal etc. Think Cerberus would be interested in that in general, a dying star.

If you read the comic you'd know that it's not a real star.

" I wonder if that's related to paragon/renegade, or the fact that the angel destroyed the human reaper and the asshole decided to keep it. "

It's an Egg! And will hatch in ME3 and will turn out to be either good or evil depending on your actions in ME2. 
 
Oh god if this actually happens I might kill myself.

It's based on the end decision you make.  I played a paragon all the way through, but made the renegade choice at the end and got a red star.

I suspect if it has ANY significance to the actual game world of mass-effect it will probably be an object that allows for mass effect travel of somekind. 
 
That's all I assumed it was when I played it. 
 
Either that or the elusive man is obviously working for the reapers in some form. But then miranda having actually been in the same room would suggest she actualy knows something about what it is. 
 
Anywayz I spent more time just gawping at mirandas tight butt.

It's not real, but it's just a big holograph of a dying star. 
 
I find that scene (my avatar) extremely powerful. The Illusive Man, a man being kept alive by cybernetics and tech, fighting for his and his own species survival... spends all day staring at something which so closely resembles himself. Smoking and drinking away.

" It's based on the end decision you make.  I played a paragon all the way through, but made the renegade choice at the end and got a red star. "

" If you read the comic you'd know that it's not a real star. "

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SPOILER WARNING: Click here to reveal hidden content.

It's the same planet that's shown at the end of Halo 3.

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