I've come to several points in my new story where I need to know the local calendar. By they I mean how long does this world take to get around its sun. How many human days is that, and how many of their local days? How long are their days? How do they divide them up?
So yay. Math. I kept finding references to something called Universe Sandbox 2 that would supposedly help me with some of that. Now, I could make this blog all about how much of a pain it was to get Steam set up, because this Sandbox thing requires the game service, or I could go into how hard it was for me to get what I wanted done, but I am reminded that this isn't an actual release, it's still under development. I will tell you that after complaining to the right person, I got the answers I needed, and I am very grateful to whomever it is that handles their social media.
I was indeed able to get a copy of the correct star (not telling yet), and found a comfy orbit in the habitable zone. The moons were another story. I wanted two moons, and I wanted them in a specific set of orbits. So no. After a few hundred years they reorganized themselves. I tried several scenarios, and finally came up with one that's pretty cool, then I found out that after about 30,000 years, it becomes unstable and the inner moon is tossed out. I almost threw out the scenario and just started over, but then it occurred to me that this would be a realistic scenario I could actually use. It might not be more than a few lines in the current story, but this is something that might come into play later. In any event, I like it.
So, if you are looking for the ability to play with orbits and moons and planets, it isn't perfect, but it sure does have great potential. The thing I think a prospective author should remember is that this is just a tool. Don't get too caught up in making your simulation perfect.
Oh, and in the settings for Steam, there is actually an option to make it NOT start up with your computer. I shut my machine off every night, and having a game service want to log me in every time I turn on my computer is aggravating. I would hope, someday in the future, that Universe Sandbox will break free of its orbit around Steam. Take this to heart, I've read your forums. People are asking for better eggs to be able to throw around, and most of your videos on YouTube are people blowing things up and smashing planets together. Your toolset reflects that.
Here's the toolset I want. Let me more easily find any star in the database and load all known potential planets. When I search and use a star, put it in that nice quick list. Don't make me search for it over and over when you have a dozen stars I don't want to see in that beautiful list. Let grab a copy of Earth as a starting point, and reformat the continents. Let me more easily set up things like a 3:2 resonant orbit. Not sure how you would do that, but with all that up front and center, I would have been very happy. As it is, I am moderately happy, and that's mainly because of how helpful your social media person is.