Nasa's amazing 'Black Marble' pictures of the Earth at night took the web by storm last week.
But eagle-eyed viewers have noticed that at least one corner of the Earth was at least a little brighter than you might expect: western Australia. which is decidedly lacking in the industrial complexes or cities usually responsible for bright lights viewable from space.
Now Nasa has revealed the source of the mysterious lights: Bushfires.
"These new images were assembled from data acquired over nine days in April 2012 and 13 days in October 2012. This means fires and other lighting (such as ships) could have been detected on any one day and integrated into the composite picture, despite being temporary phenomena.
Because different areas burned at different times when the satellite passed over, the cumulative result in the composite view gives the appearance of a massive blaze."
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