Umbra

The umbra is the darkest part of a shadow. From within the umbra, the source of light Light

Light is electromagnetic radiation [i] with a wavelength [i] that is visible to the eye [i] or, in a technical [i] ... 

 is completely blocked by the object causing the shadow. This contrasts with the penumbra Penumbra

The penumbra is that part of the shadow where the light source is only partially blocked.... 

, where the light source is only partially blocked and there is only a partial shadow. The umbra is also the comparatively dark central region of a sunspot Sunspot

A sunspot is a region on the Sun [i]'s surface that is marked by a lower temperature than its surroundi ... 

. See also * Eclipse Eclipse

An is an astronomical event that occurs when one celestial object [i] moves into the shadow of another. ... 

* Penumbra Penumbra

The penumbra is that part of the shadow where the light source is only partially blocked.... 

* Antumbra Antumbra

The antumbra is the section of a shadow [i] where an annular eclipse [i] may be viewed. ... 

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Timeline

1999   A 7.4-magnitude earthquake Earthquake An earthquake is a phenomenon [i] that results from and is powered by the sudden release of stored energ ...   strikes Istanbul Istanbul Istanbul is Turkey [i]'s most populous city [i], and its cultural, and economic [i] centre. ...   and northwestern Turkey Turkey Turkey, officially the Republic of Turkey, is a Eurasia [i]n country that stretches across the Anatolia [i] ...  , killing more than 17,000 and injuring 44,000. This earthquake is the first of a long series of unrelated but frequent earthquakes throughout the world during the years 1999 and 2000. Some connect the earthquake to the fact that the Umbra of the August 11 solar eclipse was right above Istanbul.

Encyclopedia

The umbra is the darkest part of a shadow. From within the umbra, the source of light Light

Light is electromagnetic radiation [i] with a wavelength [i] that is visible to the eye [i] or, in a technical [i] ... 

 is completely blocked by the object causing the shadow. This contrasts with the penumbra Penumbra

The penumbra is that part of the shadow where the light source is only partially blocked.... 

, where the light source is only partially blocked and there is only a partial shadow.

The umbra is also the comparatively dark central region of a sunspot Sunspot

A sunspot is a region on the Sun [i]'s surface that is marked by a lower temperature than its surroundi ... 

.

See also

• Eclipse Eclipse
  
  An is an astronomical event that occurs when one celestial object [i] moves into the shadow of another.
  

... 

• Penumbra Penumbra
  
  The penumbra is that part of the shadow where the light source is only partially blocked.... 
  
  
• Antumbra Antumbra
  
  The antumbra is the section of a shadow [i] where an annular eclipse [i] may be viewed.
  

... 

Categories:

• Eclipses