Constellations If you look at the sky where there is no light on a clear night, there are so many stars that can not count. Thousands of years ago, the ancients linked stars to create constellations named after animals, objects, and mythical figures. Each star in the constellation is only…

Parallax When an object is close to me, you can use a ruler to measure the distance. But, it isn't easy to measure when the object is away from me. In this case, how can you measure the distance? Humans have two eyes. The world with the left eye and…

Press the button of the planet you want to go. Orbital radii of the planets has applied the average.

* 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. Diurnal Motion Fix the camera towards Polaris at night, shoot for a few hours, and you'll see the…

Tidal force Earth is not an object like a point (· ), but a rigid body (●) with a certain volume, so the gravity applied to each part is slightly different. This difference in gravity applies to all celestial bodies of volume. In the case of the Earth, only seawater…

Tide is a phenomenon that the ocean surface's periodic rise and fall due to the moon and sun's gravitational pulls. Spring Tide is the highest high tide that occurs during the tide. It occurs when the Sun, Earth & Moon are in a straight line. Neap Tide is a tide…

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 example that proves it by experiments. Foucault's pendulum is a freely swinging pendulum whose…

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. Incidentally, the North Star is located in an extension of the Earth's axis of…

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 the Earth and the Moon are pretty far apart than you thought. With the…

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 sun illuminates the northern hemisphere more in June-August. So, the northern hemisphere becomes summer,…

* 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 earth is spherical, so only half of the earth's surface receives sunlight. Daytime is…

Zodiac The Ecliptic is the way the sun passes in the sky. zodiac means 12 constellations on the ecliptic. It is said that the zodiac was made in Babylonia around the 7th century BC. Constellation 1 - Aries : March 21 - April 19 Constellation 2 - Taurus : April…

Kepler and Tycho Brahe There is an astronomer before talking about Kepler (Johannes Kepler 1571 ~ 1630). That's Tycho Brahe. Tycho Brahe (1546-1601) is a famous Danish astronomer. With the development of astronomical equipment, he left a vast amount of information about the stars' location, and he made a great…

Celestial coordinate system A celestial sphere is an abstract sphere centered on an observer. All objects in the sky can be conceived as projected upon the celestial sphere's inner surface. Equatorial system The equatorial coordinate system is the most basic coordinate system around the Earth. Most celestial bodies use this…

Geocentrism, 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 the 13th to the 17th century, it was a widely recognized worldview in Christian societies, including the Roman Catholic Church. Heliocentrism, The…

Math Notepad is a web based editor to do mathematical calculations and plot graphs. It supports real and complex numbers, matrices, and units.

App HTML5: Gravitazione, problema dei due corpi

App HTML5: Prima legge di Keplero

App HTML5: Seconda legge di Keplero

This collection of interactive simulations allow learners of Physics to explore core physics concepts by altering variables and observing the results. This section contains nearly 100 simulations and the numbers continue to grow.

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