I'm slowly starting to find my way about but there are a few things I cannot workout at the moment. The colour codings of objects is one.
Most of the planets in my surrounding area have Green names but some others are White, also there are green borders around some of the debris fields.
So what do the colour codings on the Galaxy map mean?

Let's see:

Planets
Green Planets: Planets of players in your alliance
Red Planets: Your own planets
White Planets: Everyone else (including your own if you're viewing them from a moon)

DF in total res
No Border: From 1-999.999
Green Border: 1.000.000-4.999.999
Yellow Border: 5.000.000-9.999.999
Red Border: >10M

Players
Green: less than 1/5th your points
White: Between 1/5th and 5× your points
Red: 5× your points
Light Gray: Inactive for 7+ days
Dark Gray: Inactive for 28+ days
Blue: In Vacation Mode

I'm not entirely sure on the DF values, but they're close.

Cheers.

Not exactly sure on the values, but green is well under a mil, perhaps 200K or 250K, but definetely small.