Typically these objects are moving with respect to each other and their surroundings, so the resulting shadow will sweep through a region of space, only passing through any particular location in the region for a fixed interval of time. The latter object will block some amount of light being emitted by the former, creating a region of shadow around the axis of the line. Umbra, penumbra and antumbra cast by an opaque object occulting a larger light sourceįor any two objects in space, a line can be extended from the first through the second. The term is derived from the ancient Greek noun ἔκλειψις ( ékleipsis), which means "the abandonment", "the downfall", or "the darkening of a heavenly body", which is derived from the verb ἐκλείπω ( ekleípō) which means "to abandon", "to darken", or "to cease to exist," a combination of prefix ἐκ- ( ek-), from preposition ἐκ ( ek), "out," and of verb λείπω ( leípō), "to be absent". But solar eclipses, particularly total eclipses occurring at any one particular point on the Earth's surface, are very rare events that can be many decades apart. Lunar eclipses can be viewed from the entire nightside half of the Earth. It is because of the non-planar and non-circular differences that eclipses are not a common event. And if both orbits were perfectly circular, then each solar eclipse would be the same type every month. There would be a lunar eclipse at every full moon, and a solar eclipse at every new moon. If the orbit of the Earth around the Sun and the Moon's orbit around the Earth were both in the same plane with each other, then eclipses would happen every month. The type of solar eclipse that happens during each season (whether total, annular, hybrid, or partial) depends on apparent sizes of the Sun and Moon. A binary star system can also produce eclipses if the plane of the orbit of its constituent stars intersects the observer's position.įor the special cases of solar and lunar eclipses, these only happen during an " eclipse season", the two times of each year when the plane of the Earth's orbit around the Sun crosses with the plane of the Moon's orbit around the Earth and the line defined by the intersecting planes points near the Sun. ![]() However, it can also refer to such events beyond the Earth–Moon system: for example, a planet moving into the shadow cast by one of its moons, a moon passing into the shadow cast by its host planet, or a moon passing into the shadow of another moon. ![]() The term eclipse is most often used to describe either a solar eclipse, when the Moon's shadow crosses the Earth's surface, or a lunar eclipse, when the Moon moves into the Earth's shadow. An eclipse is the result of either an occultation (completely hidden) or a transit (partially hidden). Apart from syzygy, the term eclipse is also used when a spacecraft reaches a position where it can observe two celestial bodies so aligned. This alignment of three celestial objects is known as a syzygy. The shadow of an eclipse on Earth as seen from spaceĪn eclipse is an astronomical event that occurs when an astronomical object or spacecraft is temporarily obscured, by passing into the shadow of another body or by having another body pass between it and the viewer.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |