oceany: Earth

Evidence: 94 • authority: 72

Earth's rotation or Earth's spin is the rotation of planet Earth around its own axis, as well as changes in the orientation of the rotation axis in space. Earth rotates eastward, in prograde motion. As viewed from the northern polar star Polaris, Earth turns counterclockwise. The North Pole, also called the Geographic North Pole or Terrestrial North Pole, is the point in the Northern Hemisphere at which Earth's axis of rotation meets its surface. This point is distinct from Earth's north magnetic pole. The South Pole is the other point at which Earth's axis of rotation intersects its surface, in Antarctica. Earth rotates once in about 24 hours with respect to the Sun, but once every 23 hour…

Evidence: 42 • authority: 72

Sidereal time ("sidereal" pronounced sy-DEER-ee-əl, sə-) is a system of timekeeping used especially by astronomers. Using sidereal time and the celestial coordinate system, it is easy to locate the positions of celestial objects in the night sky. Sidereal time is a "time scale that is based on Earth's rate of rotation measured relative to the fixed stars". A sidereal day (also known as the sidereal rotation period) represents the time for one rotation about the planet axis relative to the stars. Viewed from the same location, a star seen at one position in the sky will be seen at the same position on another night at the same time of day (or night), if the day is defined as a sidereal day.…

Evidence: 34 • authority: 80

Another System Wherein the Earth is Situated in the Center of the World and Moves About Its Own Axis in the Space of Twenty-Four Hours

Evidence: 25 • authority: 72

A near-Earth object (NEO) is by definition any small Solar System body orbiting the Sun whose closest approach to the Sun (perihelion) is less than 1.3 times the Earth–Sun distance (astronomical unit, AU). This definition applies to the object's orbit around the Sun, rather than its current position, thus an object with such an orbit is considered a NEO even at times when it is far from making a close approach of Earth. If a NEO's orbit crosses the Earth's orbit, and the object is larger than 140 meters (460 ft) across, it is, by definition, considered a potentially hazardous object (PHO). Most known PHOs and NEOs are asteroids, but about a third of a percent are comets. There are over 37,0…

Evidence: 25 • authority: 80

Observational Indications that the Velocity of the Wireless Wave around the Earth is about 10 percent less than that of Light

Evidence: 25 • authority: 80

Curious Kids: What makes the Earth spin on its axis every day?

Evidence: 25 • authority: 80

Earth “rotates” around parked plane by use of electronics

Evidence: 25 • authority: 72

In astronomy, axial precession is a gravity-induced, slow, and continuous change in the orientation of an astronomical body's rotational axis. In the absence of precession, the astronomical body's orbit would show axial parallelism. In particular, Earth's axial precession is the gradual shift in the orientation of Earth's axis of rotation. It has a cycle of approximately 26,000 years, tracing out a double cone with a half-aperture of about 23.4°, an angle known as the obliquity of the ecliptic. This is similar to the precession of a spinning top. The term "precession" typically refers only to this largest part of the motion; other changes in the alignment of Earth's axis—nutation and polar…

Evidence: — • authority: 72

Daytime is the period of the day in which the Sun is above the local horizon in a given location. It is sometimes just called "day". During the daytime an area is illuminated by daylight, a combination of direct sunlight and indirect light from the sky. At any given time, about half of the Earth is facing the Sun and experiencing daytime. The length of daytime varies with latitude and changes over the course of the year, as the Earth moves around the Sun. Other planets and natural satellites that rotate relative to a luminous primary body such as a local star also experience daytime, but this article primarily discusses daytime on Earth.

Evidence: — • authority: 72

The Moon is the only natural satellite of Earth. It orbits Earth in an elliptical path, at a distance that varies over the year, averaging around 378,000 kilometers (235,000 mi). It completes an orbit (lunar month) in relation to Earth and the Sun (synodically) every 29.5 days. The Moon and Earth are bound by gravitational attraction, which is stronger on the sides facing each other. The resulting tidal forces are the main driver of Earth's tides, and have pulled the Moon to always face Earth with the same near side. This tidal locking effectively synchronizes the Moon's rotation period (lunar day) to its orbital period (lunar month). In geophysical terms, the Moon is a planetary-mass objec…

Evidence: — • authority: 92

Multi-sensor monitoring of a transient event in the Gran Sasso aquifer, Italy.. A novel approach in monitoring the inner dynamics of mountains, massifs, and of the Earth crust in general, involves hydrogeological measurements, as well as new generation multi-component seismic stations. Several hydrogeological stations monitor the water parameters of the large Gran Sasso aquifer. This is especially important when the instrumentation used has a high sensitivity and is able to access frequencies below 1 mHz, opening the possibility of observing very slow signals of local origin. For several years, the ring laser gyroscope GINGERINO is operative inside the underground Gran Sasso laboratory (LNG…

Evidence: — • authority: 65