Satellite Orbit Simulator (SOS)
Bringing knowledge of space flight to the masses.

This is a free Windows-based satellite orbit simulator (SOS) for educational purposes only. Use it to learn astrodynamics, orbital mechanics, and space mission design. It is the companion software for the book Space Flight isn’t Rocket Science.  It was written by Dr. Andrew Motes (US) and Mr. Alan Burgess (UK). 

Version 26 of this software is available now.  This advanced version has the following features: 
1.  Four-body solutions that include bulging Earth, lunar gravity, and solar gravity.  Therefore, it can simulate Earth, cislunar, and lunar orbits/missions.
2. Multiple satellites can be simulated simultaneously.
3.  Multiple propulsion methods: impulse ∆v, long-duration low-thrust, solar pressure.
4.  User friendly with lots of new tools for making space mission design fast and easy.
5.  User-defined launch location.
6.  User-defined Earth atmospheric drag and lift using the NRLMSISE-00 atmosphere density model.  Able to simulate atmospheric skipping.
7.  High resolution 3D imagery with mouse-controlled zoom, rotate, shift, etc.
8.  Three Earth images to choose from.
9.  Accurate star map providing realistic space background. Labels are optional.  You can also view the stars and major planets from the ground at the location you specify.
10.  Ground tracks are optional.
11.  Earth rotation, lunar orbit,  and  the Sun’s relative location are accurately synchronized with date and time. Use it to observe solar eclipses in the past or future. 
12.  Solar eclipses for your location are calculated and shown for dates and times up to February of 2100.
13.  Planet positions are calculated based on time and date.  Look angles are shown for observing these from your location on Earth.
14.  Multiple ways to enter initial conditions: ECI position and velocity vectors, orbital elements, Two-Line-Elements (TLEs), or Earth-Moon Lagrange points. 
15.  Finds and accepts TLEs based on NORAD Catalog IDs and satellite name.
16.  Simulation with play, pause, single step, forward wind, and rewind buttons.
17.  Camera view from an Earth-Moon Lagrange Point, a point in space near the satellite, the satellite itself, or your location on Earth.
18.  Save and share your projects in editable JSON files.
19.  Comes with a free book on space mission design using SOS and lots of example project files.
20.  Free for personal educational use. 

Although we believe this software is accurate and can be used for real space mission designs, it has not yet been operationally certified; therefore, no warranty of any kind is given or implied. The authors are not responsible for any damages that might occur due to use of this software.

SOS Video

SOS Video

HeWoP-F

This is highly complex Windows-based software for predicting how laser beams propagate through turbulent atmosphere. It is user-friendly yet extremely powerful.   Used for laser weapon and laser communication systems design, it is ITAR-controlled, critical US technology.  If your company is interested in purchasing a license to use this software or purchasing permanent rights to the source code, contact me by e-mail at andymotes@msn.com.

HeWoP-F Video of Beam on Target versus Time

This software will show you how much energy is deposited onto your target bucket versus time.

Books by Dr. Andrew Motes

I have written a series of short, inexpensive technical books in electronic and paperback formats.  Seven of these books are now available in the SPIE digital library.  Click here to see those.

To see a list of all my books on Amazon along with descriptions, click the button below.

Optical Waveguide Beam Propagator

This is a free scalar propagator for optical waveguides (optical fiber).  With it you can create step-index or complicated waveguide structures, like photonic crystal fibers, and then propagate beams through the waveguide. It is the companion software for the book Modeling and Simulating Optical Waveguides by Dr. Andrew Motes.  Click here to download this software, click here to download the manual, and  click here to download the example project files.

Full-vectoral Waveguide Beam Propagator

This is the full-vectoral version of the software shown above.  Click here to download this software, click here to download the manual, and click here to download the example project files.

Mom’s Math

This free children’s educational software teaches math the old fashioned way.

Introduction to Statistics, A Teacher’s Aid

This software serves as a teacher’s aide for high-school or college statistics. It has exercises the student can perform and it demonstrates curves for: normal, gamma, beta, Weibull, uniform, binomial, geometric, and Poisson probability density distributions. For these distributions, the input parameters can be varied using scroll bars and the results on the distribution curve are immediately shown.

Tell Time

Children can use this software to learn to tell time using the old fashioned analog clock.