Bright TNOs  
The brightest TNOs, including newly-discovered 2015 RR245 are shown in this simulation.

2015 RR245  
2015 RR145 is a dwarf planet that may be in resonance with Neptune.

Polydeuces is a moon of Saturn that orbits in resonance with Dione and Helene.

Simulation of our solar system's recognized Plutoids.

The Barycenter of the Solar System  
The Sun orbits the barycenter of the solar system.

Jupiter's Trojan Asteroids  
Hundreds of asteroids orbit Jupiter's Lagrange 4 and 5 points.

Potentially Hazardous Asteroids  
Hundreds of asteroids are recognized as potentially posing a threat to Planet Earth.

Nasa's Stereo Mission  
Simulations of a pair of NASA spacecraft designed to view the Sun in stereo.

Visiting Jupiter  
Simulations of the nine spacecraft that have visited Jupiter.

Visiting Saturn  
Simulations of the five spacecraft that have visited Saturn.

Saturns Rings  
A simple simulation of Saturn's A ring, B ring and C ring.

The Jovian Moons  
62 known moons orbit Jupiter. Many are in chaotic distant orbits from Jupiter

Ceres, Pallas, Vesta and Hygeia  
A simulation of the asteroid belt's 4 largest members.

Asteroid 2006 BQ6  
Recently discovered potentially hazardous asteriod 2006 BQ6 makes a close pass to Earth on July 29, 2006.

The 10th planet
Astronomers have announced the discovery of 3 new objects orbiting the Sun in the region beyond Neptune. One of them is larger than Pluto.

The Plutonian System  
Two additional moons have been discovered in orbit around Pluto.

The Arrival of the Mars Reconnaissance Orbiter  
After a 7 month journey, the Mars Reconnaissance Orbiter arrives at the red planet.

The Milky Way's Central Black Hole  
Stars orbiting a seemingly empty point in our galaxy's core suggest that a massive black hole resides there.

Pluto's 3:2 Resonance With Neptune  
Pluto orbits the Sun twice for every 3 orbits completed by Neptune.

Neptune's moon, Triton, has a retrograde orbit.

The Orbit of Spitzer  
The Spitzer Space Telescope circles the Sun in an Earth-trailing orbit.

Can an Areosynchronous Satellite Maintain A Stable Orbit?

The Kuiper Belt and the Oort Cloud
A simulation of our solar system's reservoir of comets.

The Solar System
A simulation of our solar system's planetary region.

The Complete Solar System
A simulation containing all known moons, many asteroids, comets and spacecraft.

The Lagrange 4 & 5 points.
Two objects are locked into stable orbits in a hypothetical planet's Lagrange 4 & 5 points.

A horseshoe orbit
A rotating frame simulation of an object in a horseshoe orbit.

The Geometry of Resonance
These simulations recreate the paths of test particles shown in diagrams (a) and (b) on page 325 of Solar System Dynamics by C.D. Murray and S.F. Dermott.

A simulation of our Earth and Moon orbiting around their barycenter.

A binary star system
A simulation of a binary star system with planets around both stars.

Janus and Epimetheus
Janus and Epimetheus travel around Saturn in a horseshoe orbit.

Saturn's moons Tethys, Telesto & Calypso are locked into a 1:1:1 resonance with each other. Watch as Telesto & Calypso are held captive in Tethys' Lagrange 4 & 5 points.

Saturn's moons Dione and Helene are locked into a 1:1 resonance with each other. Watch as Helene orbits Dione's Lagrange 4 point.

The Galilean Moons
Watch as the three innermost Galilean moons of Jupiter orbit in resonance with each other.

NEO Toutatis
Near-Earth-asteroid, Toutatis makes a close pass to planet Earth on September 29, 2004.

The odds were once considered as high as 1 in 37 that asteroid Apophis, also known as 2004 MN4 would impact Earth on April 13, 2029. Although it is now known that the asteroid will miss the Earth, it will come impressively close. Watch as asteroid 2004 MN4 passes through the Earth / Moon system, barely missing both the Earth and the Moon. Let the simulation run a few more minutes and watch as Apophis returns to Earth's region in 2036.

Cruithne, Earth's 2nd Moon
Watch as Earth's companion asteroid traces kidney bean shaped orbits around the Sun.

Asteroid 2002 AA29
Earth's gravity causes Asteroid 2002 AA29 to orbit the Sun in a horseshoe orbit. At times, this asteroid enters a quasi-orbit around the Earth.

The Origin of Sedna's Orbit
How did Sedna end up in its highly eccentric orbit? Astronomers Alessandro Morbidelli and Harold F. Levison have a theory. Sedna may have once orbited a brown dwarf. A close encounter with the Sun caused Sedna to be stripped from the brown dwarf and enter a solar orbit. This simulation reproduces their experiment.

Comet Shoemaker-Levy 9
In 1994, Comet Shoemaker-Levy 9 slammed into Jupiter. In this simulation you can watch the comet as it orbits Jupiter. A close pass to Jupiter in July 1992 causes the comet to break into pieces. These cometary fragments strike Jupiter in June 1994.

The 55 Cancri Star System
Three planets are known to orbit the star 55 Cancri A. This simulation illustrates the star system and investigates the dynamical orbital interactions between the planets.

100 moonlets in Earth orbit collide and merge to form 2 large moons.

Eureka! Mars Has Trojan Asteroids
Asteroid 5261 Eureka and six other asteroids share a solar orbit with Mars. Watch as the asteroids trace paths around Mars' Lagrange points in a rotating frame.

Saros Cycle
The orientation of the Moon's orbit rotates, influencing the timing of Eclipses. The nodes of the Moon's orbit complete a Saros cycle every 18 years. Watch as the plane of the Moon's orbit rotates like a warped record.

The Kozai Mechanism
The Kozai Mechanism prevents the Earth from having a moon in a polar orbit.

Continuous Thrust
Objects accelerating in different directions have their orbits altered in different ways.