Science Simulations
This simulation … Applied a geocentric coordinate system. Air friction is ignored. Covers fall and orbital motion due to Earth’s gravity. (However, the same can be applied to other celestial bodies.) Gravity Objects with mass exert … more
x y Vx Vy * The mass and gravitational constant of the celestial body were each assumed to be ‘1’. * You can edit the position and speed of each celestial body while not running. * … more
* If you are asked to access your location, please allow it. * Your personal data is not stored on the server. * For iOS devices, please allow location access as follows. Day and night The … more
Earth Rotation and Seasonal Changes The Earth’s rotation axis is tilted at an angle of about 23.5 ° to the orbital axis. Because of this inclination, seasonal changes occur like spring, summer, autumn, and winter. The … more
The photographs of the Earth and the moon close together that you can see on posters, etc., are designed to be easy to see. The moon’s apparent diameter is only about 0.5˚. This tells us that … more
Eratosthenes’ Calculation of Earth’s Circumference The first person to measure the earth’s size was Eratosthenes, an ancient Greek scientist about 2,000 years ago. Eratosthenes lived in Alexandria, near the Nile River’s mouth by the Mediterranean coast, … more
Foucault’s pendulum is a device invented by French scientist Leon Foucault to prove the Earth’s rotation in 1851. The fact that the Earth rotates has been known for a long time, but it is the first … more
Why do we always see the same side of the moon? The moon’s rate of rotation and rate of revolution is the same.
* If you are asked to access your location, please allow it. * Your personal data is not stored on the server. * For iOS devices, please allow location access as follows. day and night The … more
Latitude of Polaris Polaris is far from Earth. Thus, light from the North Star reaches parallel to the Earth. And since the earth is round, the North Star’s latitude varies depending on where it is observed. … more
Let’s measure my weight on several planets with the scale that we used on Earth. Newton explaining the gravity mathematically Every object has a gravitational field around it and attracts surrounding objects. The strength of this … more