Transhuman Space/Avatar

[Cyclone]

Let's suppose an alternate Transhuman Space, where humanity notices the presence of biomarkers on a moon of Alpha Centauri Ab (a gas giant), at some appropriate point in the timeline.

Realistically, this would greatly accelerate interest in extrasolar exploration, given the possibility of life on another planet, relatively "reasonably" close by. Let's say it accelerates the equivalent of Starswarm enough that by 2080, one or more such projects have completed, and the THS powers are aware of the broad outlines of this alien world: it is Pandora, a world dominated by hexapodal life (and the strangely-humanoid Na'vi), with a thicker atmosphere and lower gravity than Earth, though the atmosphere is unbreathable by humans due to the presence of high quantities of carbon dioxide and hydrogen sulfide in the atmosphere. These probes also revealed the presence of unobtanium on the planet. Like in the movie's universe, we'll say that unobtanium cannot be produced by human industrial processes available to the THS powers.

Given the presence of an entire alien biosphere as well as an extremely valuable room temperature superconductor on the planet's surface, the planet will naturally be of great interest to all the Earth powers. What happens next?