You will be able to download software and various files created by me from this web-page. Before you do so, please read the TERMS & CONDITIONS that apply, reached by clicking that link. Downloading anything from this web-page signifies acceptance of these terms and conditions.
This a very simplified Orbital Gravity Simulation, where the effects of the gravitational attraction by the sun and planets (Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune) is calculated on a series of randomly created "comets" and "asteroids". The initial starting positions of the planets is based on the date the application is launched, according to Keplerian Elements and principles. The comets and asteroids are distributed mostly between the orbits of Jupiter and Mars, and their paths are calculated using Newton's Laws of motion, particularly Gravitational attraction. Asteroids have a much less elliptical orbit at the start of a simulation than do the comets. The simulation is two-dimensional only, I am working on a three-dimensional version but the mathematics is complex enough in 2-D (not for the orbits, but for the code to display them sensibly on a 2-D screen). The 3-D version will probably appear as a separate file, rather than a revision to this one.
The simulation shows the action of Jupiter in particular perturbing the orbits of the asteroids, in some cases causing a collision, occasionally a capture, and often a major orbit change throwing the asteroid towards the inner planets or out into the vastness of space. This is how Jupiter "cleaned up" the solar system in its infancy - every object thrown inwards was still liable to be thrown outwards at another encounter, whilst all those thrown out were gone for good. And there is always the chance of a close encounter, or impact, with Earth!
If you think this application may be of interest, you could firstly download the manual "Gravity.pdf" (which is 95% or more complete) and see what it looks like in detail. I will freely admit at this juncture that the manual, started and added to over a long period, is somewhat disjointed. It sorely needs a complete re-write, which I shall probably do before changing its status from "draft".
Google Chrome at present downloads the file to the folder "Google Downloads", or whichever folder you specified in Google settings. You can run it from there but I advise copying it to a new folder of its own and running it from the new folder. Uninstallation then is a simple matter of deleting the new folder. So having downloaded the file, click the up arrow beside the "Discard" button and select "Keep". Right click on the filename and select "Show in Folder". Click on "Gravity.exe" and scan it with your virus checker. If all is OK, do a copy, then navigate to and create the folder for it, then paste it into the folder. When you first run it, Windows 10 tells you it protected your computer, click "More Info" and click "Run Anyway". Once running, click the menu option "Windows" > "Auto Arrange Windows" which will try and set the window positions to suit your monitor. Close the about, help, preferences, commentary and other windows leaving open only the main window, and the "Information" and "Controls" panels. When you next run, it should open without any warnings.
| WARNING : DOWNLOADING ANY FILE SIGNIFIES ACCEPTANCE OF THESE TERMS AND CONDITIONS! | ||||||
|---|---|---|---|---|---|---|
| File Download Link | Version | Filename | Filesize | Download Time* | Screen Size | Comment |
| Orbital Gravity Executable | 2.5.03 | "Gravity.exe" | 1.2MB | 35 secs | 1090W 960H | Corrected a few minor things. |
| Draft | "Gravity.pdf" | 3.3MB | 35 secs | I have removed the Gravity.pdf manual from download as it has become too much out of date, and was never complete in the first case. I have tried to embed some help in the application itself, and will concentrate on making that more accurate and helpful. Once I am happy, I will regenerate the PDF manual from the application help. | ||
* The download time shown is approximate for connections with two speeds. The fastest would be fibre broadband, and corresponds to my current speeds with BT Infinity. The slower value was a non-fibre broadband connection I previously had with Talk-Talk. Both are based on the "upload" time for me to load the file onto my web-site using Filezilla [version 3.33.0]. You can easily test your own broadband speed by downloading the free application "Network Speed" from the Windows App Store.
The image below is a grab from a Solar System simulation using version 2 of the software. The main thing still incomplete is the new Help pages. The view for the main window is centred to track object Comet13 which is just about to have a close encounter with Jupiter. This simulation is built-in to the application, as "Demonstration 1" found under the "Simulation" main menu option.
I am soon going to abandon this application. It is a good simulator (in my view!) but I have decided that to truly simulate Newton's Laws of Gravitational Attraction in a solar system, I will need to stop using Kepler and use Newton throughout. So whilst I may place the planets of a "real" solar system simulation in their actual positions when a simulation is created, I will not maintain their orbits by Kepler, but by Newton. So I will offer the user the ability to simulate our actual solar system, or a completely random system, perhaps with binary star systems, for which no Kepler elements would be available, and simulate them all by Newton. It will be fun seeing how it all works! (I have a devilish plan to introduce a passing super-massive "black hole" during a simulation and see what happens). The challenge is the starting conditions for these bodies, which will depend on these random conditions. And the starting conditions for objects orbitting close to a binary system is a significant issue to resolve!
Unfortunately, I do not have any means of establishing the minimum hardware specification required to run my software. All I do know is the specification of my computer, on which the software was developed, tested and which runs satisfactorily.
Original Computer specification:
In May, 2018, I purchased a new PC with a significantly upgraded specification:
* I have tried to design my software to present a smaller window size than my monitor permits, as I am concious that many people will have a smaller monitor than listed above. I will provide the maximum window size I use with each application's details.
If you use the software on a PC with a different set up, let me know if you have any issues with running the application, and if it works and you have the time, please let me know what your specification is. It should work on all flavours of Windows from SP, Win7 to Win10. I did have a lot of memory in my original set up - well, 4 GB was a lot in 2010!
I need to include something for this, but it won't be a miles long "Agreement" that you see with most software these days. "File(s)", "Software" and "Application" have the same meaning herein. "You" are the person who downloaded the file(s) from this web-page, and these conditions also apply to anyone to whom you pass on the file(s).
Terms compiled and added to web-page 19th October, 2016.