Saw this in the Pioneer thread, looks a little like an updated Notis, so if you feel like a relaxing sail around the universe with out having to fight any one this may be worth a look. HavenÃ¢â‚¬â„¢t tried it yet myself as my hamster powered PC is unlikely to run it.
* There are all types of space objects represented: planets and moons, stars, star clusters, nebulae, galaxies.
* Motion of the observer in not limited.The transition between any bodies and any scale occurs continuously. Control like in shooters (WASD). There is a mode of motion with inertia.
* "Selected and fly" autopilot: just click on the object with the mouse and hit the 'G' key to automatically fly toward him.
* Search for objects by name, map of the planetary system, saving locations, autopilot's journal.
* Motion of the planets in orbits are calculated in real time, possibly acceleration, deceleration and reversal of flow of time.
* Showing the orbital paths of the planets, labels, grid.
* Automatic binding of the observer to the moving object and automatically select the optimum flight speed.
* Known objects are represented by catalogs: galaxies (NGC / IC), stars (HIPPARCOS), star clusters, nebulae, planets (Solar system and known extrasolar planets).
* There are the procedurally generated objects in the unexplored areas: stars, star clusters, nebulae, planetary systems.
* Volumetric 3D sprite models of galaxies and nebulae including light-absorbing dust clouds, optimized render to a skybox and impostors.
* 3D lanscape of the planets and the stars: for many Solar system bodies there are actual data from space probes, for procedural planets there are procedural generation of surface.
* Lighting effects: lens flares, solar eclipses, shadows of the rings, the lighting of the planetary bodies by each other.
* The exact model of the Earth's atmosphere (code by Eric Bruneton), adapted for the other planets.
* Ability to import users addons: the models, catalogs, and textures.
It's a gorgeous little thing. You can download the latest version from http://applesforgeeks.com/space-engine-update-released/ In case you can't navigate the Russian site 🙂