As seen from the Earth, a solar eclipse occurs when the Moon passes between the Sun and the Earth, and the Moon fully or partially blocks the Sun. This can happen only during a new moon, when the Sun and the Moon are in conjunction as seen from Earth. In a total eclipse, the disk of the Sun is fully obscured by the Moon. In partial and annular eclipses only part of the Sun is obscured. At least two, and up to five, solar eclipses occur each year; no more than two can be total eclipses. Total solar eclipses are nevertheless rare at any particular location because totality exists only along a narrow path on the Earth's surface traced by the Moon's shadow or umbra.
An eclipse is a natural phenomenon. Nevertheless, in ancient times, and in some cultures today, solar eclipses have been attributed to supernatural causes or regarded as bad omens. A total solar eclipse can be frightening to people who are unaware of their astronomical explanation, as the Sun seems to disappear during the day and the sky darkens in a matter of minutes.
As it is dangerous to look directly at the Sun, observers should use special eye protection or indirect viewing techniques. People referred to as eclipse chasers or umbraphiles will travel to remote locations to observe or witness predicted central solar eclipses.
The last total solar eclipse was on July 11, 2010; the next will be on November 13, 2012. The solar eclipses of 2011 were all partial eclipses; the last one occurred on November 25, 2011. The next solar eclipse will be an annular eclipse on May 20, 2012.
An eclipse is an astronomical event that occurs when an astronomical object is temporarily obscured, either by passing into the shadow of another body or by having another body pass between it and the viewer. An eclipse is a type of syzygy.
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. 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. A binary star system can also produce eclipses if the plane of the orbit of its constituent stars intersects the observer's position.