Glossary term: Solar Eclipse

Description: A solar eclipse occurs when the Earth, Moon, and the Sun are arranged in a straight line, with the Moon between Earth and the Sun. When observed from the surface of the Earth, the disk of the Moon covers the disk of the Sun in the sky; from space we can see the shadow of the Moon moving across the sunlit side of the Earth.

There are different types of solar eclipses. Total, when the disk of the Moon completely covers the Sun; partial, when only a fraction of the solar disk is covered even at maximum eclipse; and annular, when the Moon is farther away than average and hence appears smaller than usual allowing a ring of the solar disk to remain visible even at the maximum extent of the eclipse.

During a total solar eclipse, the darkest point of the shadow of the Moon on Earth is called the "umbra", and the edge of the shadow is called the "penumbra". Observers in the umbra see a total eclipse while observers in the penumbra see a partial eclipse.

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Term and definition status: This term and its definition have been approved by a research astronomer and a teacher

The OAE Multilingual Glossary is a project of the IAU Office of Astronomy for Education (OAE) in collaboration with the IAU Office of Astronomy Outreach (OAO). The terms and definitions were chosen, written and reviewed by a collective effort from the OAE, the OAE Centers and Nodes, the OAE National Astronomy Education Coordinators (NAECs) and other volunteers. You can find a full list of credits here. All glossary terms and their definitions are released under a Creative Commons CC BY-4.0 license and should be credited to "IAU OAE".

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The Moon appears as a black circle, blocking light from the Sun. A faint glow from the Solar corona surrounds the Moon.

Total Solar Eclipse

Caption: This image represents the total solar eclipse as observed from Kurigram in Bangladesh. Solar eclipses occur when the moon, as seen from earth, passes in front of the Sun. The moon is much smaller than the Sun, it is closer by the night amount that the angular diameters of the Sun and moon are almost the same (~approximately 1/2 a fingertip). Therefore, the moon can cover up the Sun's disk when it passes directly between the Sun and the Earth. The ring of light around the black circle is called the corona.
Credit: Lutfar Rahman Nirjhar credit link

License: CC-BY-3.0 Creative Commons Attribution 3.0 Unported icons