The prime purpose of Gravitorium is to let you play with ideas about gravity and gravitational systems. While it's not intended to be a highly accurate solar system simulator, at low speeds its accuracy is really pretty good. And, best of all, it lets you "play universe maker". Throw in a few extra planets, add a black hole, set a comet plunging towards the Earth! Or create an entirely new solar system from scratch. Gravitorium Pro is licensed as shareware, the cost of the registered verison is $17 and full size of the download is 2.7 MB. You may download a free version of Gravitorium Pro by following download link at Free Download section of this page. Gravitorium Pro is developed or distributed by Rightword Enterprises and is listed under education science astronomy physics.