My Solar System

PhET Interactive Simulations
Type Category
Instructional Materials
Interactive Simulation
This resource, vetted by NSTA curators, is provided to teachers along with suggested modifications to make it more in line with the vision of the NGSS. While not considered to be “fully aligned,” the resources and expert recommendations provide teachers with concrete examples and expert guidance using the EQuIP rubric to adapted existing resources. Read more here.



My Solar System is an orbital simulator which students use to investigate how mass, position and velocity affect gravitational forces.  Students can either select from ten preset scenarios, ranging from simple sun-planet-moon simulations to more complex situations such as Trojan asteroids or Four Star ballet, or they can create their own scenarios by selecting and dragging symbols into position. An additional option is available: users can decide whether or not to have system centered movement. When the simulation is run with this option disabled (unchecked), students will see that all objects are in motion. The creators note a few limitations of their model. First, the simulation lacks force vectors. Next, units of mass are not specified and, finally, objects’ masses should not exceed several thousand units.  Note:  students can either run the simulation from the webpage or can download the file.  Java is required. Additional Teacher Resources are available if users register for a free account. Although this simulator can be used in both middle and high school classrooms, this review reflects middle school Performance Expectations.

Intended Audience

Educator and learner
Educational Level
  • High School
  • Grade 8
  • Grade 7
Access Restrictions

Free access with user action - The right to view and/or download material without financial barriers but users are required to register or experience some other low-barrier to use.

Performance Expectations

MS-ESS1-2 Develop and use a model to describe the role of gravity in the motions within galaxies and the solar system.

Clarification Statement: Emphasis for the model is on gravity as the force that holds together the solar system and Milky Way galaxy and controls orbital motions within them. Examples of models can be physical (such as the analogy of distance along a football field or computer visualizations of elliptical orbits) or conceptual (such as mathematical proportions relative to the size of familiar objects such as students' school or state).

Assessment Boundary: Assessment does not include Kepler’s Laws of orbital motion or the apparent retrograde motion of the planets as viewed from Earth.

This resource is explicitly designed to build towards this performance expectation.

Comments about Including the Performance Expectation
In order to gain the most benefit from this simulation, middle school students should begin with the easier preset scenarios: sun and planet or sun, planet and moon. Once, they understand and can explain their observations of gravitational forces, then they should be encouraged to investigate the more complex scenarios. Teachers should understand that whether students use the preset or create their own scenarios, they are still just using, not developing, a model to describe gravity’s role. Students should record their observations so that they can be analyzed and used to construct explanations of gravitational forces.

Science and Engineering Practices

This resource is explicitly designed to build towards this science and engineering practice.

Comments about Including the Science and Engineering Practice
As indicated above, students are using, not developing, a model to explain the role of of complex phenomena, in this case, the role of gravitational forces. Overall, the simulation provides a high level of interactivity as users can select from ten preset scenarios and can manipulate up to four variables. Teachers should encourage their students to make and record predictions prior to running each simulation; once the scenario has been run, students should record their observations. In order for students to keep track of the different scenarios and results, teachers may wish to design a data table for them to use while creating and running their simulations.

Disciplinary Core Ideas

This resource was not designed to build towards this disciplinary core idea, but can be used to build towards it using the suggestions provided below.

Comments about Including the Disciplinary Core Idea
As presented, My Solar System allows students the ability to investigate gravitational forces in an imaginary solar system. Although the same gravitational forces apply in our Solar System, this simulation is not meant to mirror our reality. As indicated in the Help section, the authors caution that distance, mass and velocity units are arbitrary and that this simulation only works for masses of a few thousand units.

Crosscutting Concepts

This resource is explicitly designed to build towards this crosscutting concept.

Comments about Including the Crosscutting Concept
In this simulation, students are allowed to change four variables: number of bodies (up to a maximum of four), mass, position and velocity. Students will immediately see the effect of changing any of these variables on orbital paths. Teachers should remind students that in order to construct an explanation for the effect of a variable on gravity, only one value can be changed during a single run of the simulation.

Resource Quality

  • Alignment to the Dimensions of the NGSS: In My Solar System, users investigate gravitational forces in orbital systems by manipulating the mass, position and velocity of selected objects in either preset or self-designed scenarios. Students gather their data by employing the Practice of Modeling, using a simulator designed by PhET. Both the Disciplinary Core Idea of gravitational forces and Crosscutting Concept of Cause and Effect are interwoven in each run of the model. For example, students immediately see how changing variables in the simulator affects gravitational forces as observed in the outcomes.

  • Instructional Supports: Although specific planets or asteroids are not identified in the simulation, My Solar System still presents scientifically accurate scenarios in an engaging format. The simulation is grade appropriate for middle school students; however, some students will need additional supports in order to achieve success. Most middle school students would need to start with the simpler preset scenarios such as sun and planet or sun, planet and moon; if they can describe what is going on in these instances, they could then progress to work on the more challenging scenarios. Tips for differentiation are not included. Students may also need guidance in expressing and representing their ideas and responding to feedback. Students who need a greater challenge could be directed to create their own scenarios.

  • Monitoring Student Progress: The creators do not provide any means to assess student progress; however, teachers could monitor the progress of three dimensional learning through anecdotal observations. Several teachers have submitted activities which can be found under the “For Teachers” tab located under the download button. Several of these activities have been written specifically for the middle school student and include both scenarios and questions for students to investigate. Formative assessments, aligned rubrics and scoring guidance are not provided.

  • Quality of Technological Interactivity: My Solar System is both a high interest and challenging simulation that allows students to select scenarios and manipulate variables in order to investigate how mass and velocity affect orbital paths. Students will instantaneously see the effects of changes to variables, whether it be an object flying off into space, crashing into another object or maintaining an orbital path. From their observations, students will be able to construct an explanation for the role of gravity in the motions within galaxies and the solar system.