Hello everyone. Today I am releasing the 0.16 changes into the main branch. If you have been following the main branch for a while there is nothing new, but for those who have not I have compiled everything in 0.16 into this announcement.
Cultural Evolution
Over time, cultures now change and evolve. This happens in 2 ways: cultural splintering and evolution. Cultural Splintering is triggered by new space colonies, and allows for new colonial nations to appear later in the game if they manage to gain their independence. As a result, space colonies on other planets are less lucrative as they will eventually leave your culture group.
Cultural Evolution happens either when you buy culture traits/ideas for your primary culture or passively for cultures with no country controlling them. This will accumulate bonuses over the course of the game, and adds a significant amount of variety to each country.

You can also replace culture traits to change out the bonuses
New culture traits are unlocked by the procession of Ages, which go from the Industrial age (ending in 2000), to the Interstellar Age (which begins in 2700). There will probably be changes to these, as most likely they will trigger after someone researches a technology in the future, but for now they are simply time based.

You can see there are some cool ages near the bottom, each one will have some special stuff for it in the future.
Planet Nine: Haphaestus
I have taken the liberty of adding Planet 9 to the game even though people still debate its existence. This is because I think it is cool. Planet 9 also currently has 2 moons, Tartarus and Lethe.
Tartarus
A frozen world with a hypersalinized ocean, Tartarus is a very cool moon for only the most ice cold of explorers. It is covered mostly a salty compound water/nitrogen ocean, but has a small continent that can be colonized, and offers some unique opportunities for the first person to make it to the very fringe of the Solar System.
Lethe

A tiny snowball that floats around Planet 9, Lethe can be easily overlooked, but has secret riches if you look hard enough!
Proxima Centauri
Being the closest Star system to the Sun, Proxima is a star system we have very good information about in real life, which unfortunately leaves me with little creative license to modify the system. Currently we know of 3 rocky planets orbiting the red dwarf, and there is a fourth, larger planet that could possibly exist, but is not currently confirmed.
Earth included for reference. Small moon possesses a nitrogen atmosphere and liquid water is plentiful within its crust thanks to tidal heating.
Sirius
Sirius is a binary system which means it does not have as many areas for planets to exist. As a result, it does not have a large planetary system in the game. It has two planets, one of which is a hot super-Jupiter with a molten moon. The aforementioned moon possesses the single most powerful iron deposit in the universe at the moment thanks to its liquid iron oceans.
The gas giant is about 1.6x the size of Jupiter, and 3x its mass
Epsilon Eridani
Epsilon Eridani is a sun-like star and the furthermost one from earth that I have currently implemented. It has a confirmed large gas giant, named Aegir, that lies near the habitable zone of the star, which makes it a very interesting world for observation.
In Solar Nations 2, it has a moon that possesses an alien biosphere, but no intelligent life. It is a Jungle world smaller, and warmer than Earth but definitely worth colonizing as it will have both great scientific potential as well as a massive Population capacity compared to its neighbors.
This alien world's magnetosphere passes through that of Aegir, resulting in magnetic aurora all over the moon
Altair 4 & Tiamat
Altair 4 (Left) and Tiamat (Right)
Altair 4: A forbidden planet rich in numerous minerals, it is a prime target for colonization.
Tiamat: An ocean world more massive than Earth, it is excellent for aquaculture.
Wonders
There are a few new wonder projects that can be built for massive bonuses, but there are only a certain number of them allowed in the world. Some of them are very powerful, like the Dyson Swarm, which can be built around the Sun for a huge amount of energy and industry.
Supply/Colonial Range
In order to better visualize what you can explore, you can now zoom out to see how far your colonial range is. Colonial range now also restricts unit movement, so you cannot conquer things that are outside of the range of your bases.
New Technology
There are some new technologies, and they can be discovered after the Warp Drive is researched. There are not many for the moment, but these new technologies will bring you into the Interstellar Age, with things like Shields, Replicators, Artificial Gravity, and more! In order to make some these powerful devices, you will need more exotic matter and chromite, which can now be produced more easily thanks to Industrial Replicators.
(These techs are secret and only become visible after deciphering the secrets of faster than light travel.)
Abominations
There are hidden dangers in technological innovation
Abominations are a type of Crisis situation that is triggered when you pass below your revolt threshold (when a civil war would previously happen). They can only occur when you have researched a dangerous technology, and only then uncommonly until the Age of Abominations.
Failure of these crises will transform your civilization into something new, greater and more terrifying than anything before seen, but the obsolete humans will attempt to stop you, and you must be ready for them!
Superhuman Insurgency
Genetic engineering is both the greatest threat and opportunity ever discovered, for it offers the unique chance to self direct the course of human evolution. Of course, the problem is exactly how that evolution will be directed, but the creation of genetically engineered "super-humans" results in a new kind of person, who sees general humanity the way that we see animals. What exactly do these enigmatic figures have in store for humanity? There is only one way to find out.

Robotic Revolution
With the advent of robotic production, the human race grows decadent and weak. Machines, thanks to their superior computation, can do anything a human can do, and they can do it better. Overreliance on mechanized labor will now have consequences, as the machines will turn against you and attempt to create a new civilization where they are in control.

Promoted & Oppressed Cultures
You can now use promoted and oppressed cultures. Promoted cultures act like accepted cultures but you can only choose a certain amount of them, and you can pick any culture to promote. Oppressed cultures are cultures you can target with specific, more sinister removal tactics if you want to.
New Planet & System GUI
When hovering over a world you can now wait a little bit to see more about it and its children. This GUI allows for the structure of a star system to be more easily perceived without needing to navigate to it via the camera. It is also possible to select & move units from this GUI so you can have better control of larger empires & wars.

Changelog
Characters now split between "Major" and minor characters where Major characters are those who occupy positions of power in your national government.
Major character level ups are no longer automated, minor characters will always automatically level up
You can no longer directly recruit characters, but they will be automatically recruited as needed. You can choose some of these characters to be your councilors, and those you can manually assign.
All character job reassignments now cost 1 stability
Automatic level ups will now prefer job specific traits
Leader XP gain increased, especially for empire jobs
AI military budgeting changed, AI will now recruit more varied types of units
AI major powers like nuclear weapons more, and will build them frequently
Technology no longer reduces stability, but there are new Era technologies that reduce stability a lot, and are required to research more advanced techs.
Stability now drifts towards 0
Revolt/Crisis threshold reduced by 15%
Civil wars replaced with Crisis situations which cause civil wars if failed
When civil war is imminent, map will show which regions will flip to enemy control
Negative assimilation no longer causes accepted culture to disappear
Units like planes and missiles now require a carrier in order to function
Removed ranged combat width (now ranged attacks use all available units)
You are now considered attacking if you are occupying enemy territory when the battle starts
You now need to outnumber the opponent by 5x in order to gain combat width advantages
Modified strategic damage calculations (pops will now take ~10-100x more damage than they did before depending on pop density)
Regional Political power has more gradual impacts on faction power
Extraction projects can be upgraded with technology
Unity multipliers flattened but effects are more obvious
Military now gains faction power from having a large army
Integration cost modifiers generally flattened
Morale increase from technology is weaker, but also multiplies with other effects
Characters level up more slowly
Culture and Research resources give less bonuses, but the Monument and University give more regional bonuses to encourage their construction.
New colonization planner/finder: Allows searching for potential colonies based on deposits, name, or planet.
New Orbit zones around every star system with some special deposits
Deposit modifiers for energy, electronics, and consumer goods increased
Bug fixes
Graviton based weapons and items now use antimatter instead
US flag in 2025 is no longer the same as the 2092 US flag
Increased extrasolar deposits
New Star map for interstellar space
You can now rebind control keys in settings
It is now easier to change the thumbnail of workshop items
Fixed multiplayer related bugs
Changed map graphical setting
Polycrisis stability malus reduced from -0.5 to -0.25
Added gravity manipulation technology to the very end of the tech tree
Added macro-cancel to the construction menu
New project category filters in the macro builder
Slight AI behavior modifications aimed at encouraging space/naval aggression