# Astronomy Simulation

## Zodiac

Zodiac The Ecliptic is the way the sun passes in the sky. zodiac means 12 constellations on the ecliptic. It is said that zodiac was made in Babylonia around the 7th century…

## Diurnal Motion of North Sky (WebGL)

* This is a web page using WebGL technology and do not work in Internet explorer. Diurnal Motion Fix the camera towards the Polaris at night. When you shoot for a few…

## Tidal Force

+ = Tidal force Because the earth is not a point(·), it is a rigid body(●) with a certain volume, so the gravity on each part is slightly different. This difference in…

## Galilean Moons

Jupiter, the largest planet in the solar system, has many satellites. Jupiter’s representative satellites are Io, Europa, Ganymede, and Callisto. These four satellites are called Galilean satellites. Galileo observed that these satellites…

## Path of Satellite

As the satellite orbits the Earth from pole to pole, its east-west position wouldn’t change if the Earth didn’t rotate. However, as seen from the Earth, it seems that the satellite is…

## The Geocentric Theory and the Copernican Theory

Name of the Orb Run The Geocentric theory The Geocentric theory is a cosmic perspective in which the Earth is at the center and all the stars revolve around the Earth. From…

## Why does the moon rise 50 minutes later each day?

Run Why does the moon rise 50 minutes later each day? As the earth spins once a day, the moon moves slightly eastward. So it takes 50 minutes longer than 24 hours…

## Foucault Pendulum (WebGL)

Earth fixed Latitude * This is a Web page using WebGL technology and do not work in Internet explorer. Foucault’s pendulum is a device invented by French scientist Leon Foucault to prove…

## Earth’s Revolution and Seasons (WebGL)

Zoom View * This is a Web page using WebGL technology and do not work in Internet explorer. Earth Rotation and Seasonal Changes The Earth’s axis of rotation is tilted at an…

## Horizontal Coordinate System

Touch the screen to move the position of the star. How many numbers do we need to indicate the position of the star? After some time, is this star in the same…

## Why do we see only one side of the moon?

Why do we always see the same side of the moon? The moon’s rate of rotation and rate of revolution is the same

## Diurnal Motion of Sun

Diurnal Motion is the changing view of the sky seen as the Earth rotates on its axis. What is the change in the movement of the sun during one year? What changes…