Tocoincidewith Earth Day on April 22 , a day we take to consider just how incredible our major planet is , a beautiful atmospherical phenomenon known as the " Belt of Venus " will be visible just after sunset . This pink band across the sky can be seen on unclouded days at sunrise and sundown – though it ’s more pronounced and easily get wind at sunset , hence its other name , an " anti - twilit arch " .
identify for the girdle worn by the Romanic goddess of passion , not the major planet , you should be able-bodied to see it as the sun dips below the horizon in the west ( in the Northern Hemisphere ) if you do an about - twist and face east . You ’ll see a band of pink - orange tree with a band of blue underneath . This blue bar , which is disconsolate than the circumvent twilight , is Earth ’s " shadow " beingcaston the atmosphere . These bands of colouration will appear to be moving upwards in the second follow sundown , eventually forming an archway across the sky before fading as night sets in .
So , what is happening here ?
Well , Earth ’s shadow ascend can be seen on any unclouded solar day in the opposite direction to sundown , ascend at the same pace as the Sun going down . As Earth rotates , sunlight ceases to contact parts of the atmosphere near Earth ’s horizon on the diametric side of the sky than the Sun . Earth ’s shadow is being cast on the standard atmosphere , as it is no longer reflecting sunlight .
The anti - twilit arch also appear in the opposite direction to the Sun ; anti - twilight substance opposite twilight . We see this arch when the Sun is just below the visible horizon but some light is still pull in its way through the atmosphere . It appears a rosy - hue colorbecausered light has the long wavelength , so it ’s able to go far through the standard pressure . At the decimal point opposite the sunset , the light is scattered through the denser atmosphere and back towards our eyes . This " backscattering " creates the pink band .
As Earth ’s tail is emerging it appears to make the pink band separate from the horizon , emphasizing the archway , and that is the Belt of Venus .
