Features of the addon:
4-10 Tier Rockets
Electric Rocket (1.8.9/1.10.2/1.11.2/1.12.2 only!)
Custom Launch pads
Custom Vehicles
Multi Biome Systems for most Moons and Planets (MC 1.7.10 is currently missing one biome, but will be added very soon)
Different Gravity/Temperature/Day Length for each Planet and Moon
Dungeons Tier 4 -10(Pluto & Eris still is a Creeper Bosses, but they will be replaced very soon!)
Tier 2 - 4 Thermal Armour (Tier 3 - 5 in 1.8.9/1.10.2/1.11.2/1.12.2! Due to GC adding Tier 2)
Custom Tools for most materials
Custom Ores on every Planets and Moons
Custom Config options (Including Compatibility options for other GC Addons)
Custom Armor for most materials
Villages on All Planets
Villages on All Moons (v1.7.10 only!)
Custom Batteries
Custom Non Boss Mobs(Entities) (v1.7.10 only!)
Custom Achievements
Space Stations for each of the Planets
Forge Microblocks support (v1.7.10 only!)
Custom Space Suits Tier 1 - 4, Including Gravity Boots (MC 1.8.9/1.10.2/1.11.2/1.12.2 only!)
Custom Radiation and Pressure System for planets, including onscreen displays (MC 1.8.9/1.10.2/1.11.2/1.12.2 only!)
Custom Machines to support Radiation and Pressure System
Upgraded versions of some of the Galacticraft Machines
NEI/JEI Support
Extreme Reactors Support (1.10.2/1.11.2/1.12.2 only!)
Other Galaxies/Galaxies Selector (MC 1.8.9/1.10.2/1.11.2/1.12.2 only!)
Extended Galacticraft Galaxy Map Screen with Extra Information
CraftTweaker Support (WIP, 1.12.2 Only!) See Here for Methods
Dynamic Surroundings Support - via official config files here
And more....