Celestial event
An astronomical event is a more or less rarely held event which has its origin outside the Earth. Examples include: bright comets, rare eclipses or planetary encounters, supernovae in neighboring galaxies or extraordinary phenomena in the Earth's atmosphere.
In contrast, the umbrella term for celestial phenomenon occurring more often, with the naked eye visible phenomena used in the sky, for example, on and sunsets brighter stars, twilight effects, atmospheric halos, planetary grinding and conjunctions, Variable Stars and the like. They are in the article
Overview
The most astronomical events relate to objects in the solar system, or to those in which one of the participating body is part of our solar system. Astronomical events that do not originate from bodies in our solar system, mostly due to unusual changes of stars.
As an astronomical event is also referred to rare phenomena in the Earth's atmosphere, such as light phenomena, electromagnetic effects or larger meteors that strikes from space on earth.
The events in astronomy also some that are not observed in the visible spectrum ( Visual Astronomy ) count (eg, gamma-ray bursts ) or in a broader sense those who take too long to be perceived to humans as an event (in the extreme case, about a Galaxiendurchdringung over many millions of years).
However, many of these astronomical events can not be predicted because of their unerwartenen occurrence.
Predictable events
- Conjunctions between the sun, moon, planets, asteroids, periodic comets with each other or with fixed stars, and other aspects
- Transits ( passages coverages ): occultations and transits of stars, planets from the sun (Mercury passages, Venus passes), the moon, planets, asteroids or comets periodic
- On and sunsets, twilights, White Nights, Polar day and night
- Solar eclipses and lunar eclipses,
- Passage of the apses and nodes of planets, moon, asteroids or comets periodic
- Brightness maxima and Helligkeitsminima of periodic variable stars
- Double Star passages and the movement of exoplanets
- In space and missile launches, orbital maneuvers or Rendezvous
Predictable astronomical events are usually listed in the astronomical yearbooks.
Due predictable events
- Close encounters and impacts, such as particular near-Earth objects on Earth: Although meteors meteorites, bolides and falling stars were theoretically predictable, but in practice they are not detected due to their size and frequency. The collection of large near-Earth objects is one of the urgent problems of modern observational astronomy
- Phenomena of the atmosphere, their immediate causes lie outside of it
- For example, the twilight
- Maxima and minima semi- regular variable stars
- Photo meteors ( phosphenes ): Northern Lights, zodiacal light, halo and glory, and other
- Polar light, Cherenkov flashes
Nichtvoraussagbare events
- Emergence of non- periodic comets
- Novae and supernovae
- GRBs (Gamma Ray Bursts )
- Any extraterrestrial signals as she searches about the SETI project
- Events that have never been there and still follow from any theory, we therefore do not know.