The color of Earth’s sky has changed over time due to the presence and activities of different life forms. Initially, the sky had a grayish-blue-green tint due to a nitrogen and carbon-dioxide-rich atmosphere with little oxygen. Methanogenic bacteria then turned the sky orange by producing methane, which formed hazes that absorbed blue light. Eventually, cyanobacteria produced oxygen, which cleared the haze and restored the sky to its current blue color.
Related Posts
Ancient Bacteria May Have Paved the Way for Earth’s Mountains to Form—Almost Literally
The various mountains that surround the landscape stand testament to the great forces of nature that continuously shape…
Animals Have Been Around For a Long Time—Perhaps Even Longer Than We Once Thought
A recently-discovered group of fossils, dating back almost a billion years, revealed a once-thriving microbial ecosystem of prokaryotic…
Yes, “Doggerland” Is a Real Place—And Its Role in Human Evolution and Dispersion Is Critical
Coastal strollers along British beaches have occasionally reported sightings of old wooden tools and even human bones along…
What Makes Us Human?
Scientists say our human DNA is roughly 96-99% identical to that of chimpanzees, our closest living primate relative…