The Sahel<span> </span><span> is the ecoclimatic and </span>biogeographic zone<span> of </span>transition<span> in </span>Africa<span> between the </span>Sahara<span> to the north and the </span>Sudanian Savanna<span> (historically known as the </span>Sudan region<span>) to the south.</span>
<span>The Sahel is the ecoclimatic and biogeographic zone of transition in Africa between the Sahara to the north and the Sudanian Savanna to the south.</span>
The crab nebula consists of an oval-shaped mas of the filaments and they are imprints of the progenitor star that surrounds the diffused blue region and is helium-rich, other than gold other elements like the iron, oxygen and the uranium are produced.
