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Eclipses, Occultations and Transits

An eclipse is the result of the total or partial masking of a celestial body by another along an observer’s line of sight. Solar eclipses result from the Moon blocking the Sun relative to the Earth; thus Earth, Moon and Sun all lie on a line. Lunar eclipses work the same way in a different order: Moon, Earth and Sun all on a line. In this case the Earth’s shadow hides the Moon from view. An occultation occurs when a celestial object is eclipsed by the Moon or another solar system body. A transit is either the act of one celestial body passing in front of another or the time at which a celestial object is highest in the sky. The time at which a celestial object crosses the meridian is called the transit time.

Featured Images

Total lunar eclipse

Lunar Eclipse January 20, 2019

Sketches of the total solar eclipse of August 1868

Solar Discovery August 17, 2018

Total lunar eclipse, 2014

Super Blue Lunar Eclipse January 30, 2018

Baily's Beads around the Moon

Brilliant Beads August 21, 2017

Solar eclipse sequence

Anatomy of an Eclipse August 20, 2017

Proper eye protection is needed for safe eclipse viewing

Safety First! August 18, 2017

The Sun sets behind a NASA WB-57F Canberra research aircraft

Chasing a Shadow August 17, 2017

The Sun's corona shines around the intervening Moon during a total solar eclipse

Solar Mystery August 16, 2017

Map showing the circumstances of the August 21, 2017, total solar eclipse

The Right Path August 14, 2017

Annular solar eclipse

Fiery Ring August 31, 2016

Moon-Aldebaran occultation

Vanishing Act July 28, 2016

Mercury transits the Sun, May 2016

Little Black Dot May 10, 2016

2006 transit of Mercury

Spotty Sun May 6, 2016

Total lunar eclipse, October 2014

Lunar Eclipse September 26, 2015

Space-based view of solar eclipse of March 20, 2015

Disappearing Sun March 20, 2015