
Was the colour of the sky blue during the dinosaur era?
When we gaze up at the sky, it's easy to assume it's always looked blue all through the years. After all, the sky's colour is such a consistent backdrop in our daily lives. But Earth's past is full of unimaginable changes, like shifting continents, evolving life, and even an ever-moving position of our galaxy in terms of the shifting universe.
But was the colour always the same shade?
A NASA research scientist, Jessie Christiansen, explained that the night sky, and possibly even the daytime one, may have looked a little different during the age of dinosaurs. The reason isn't just atmospheric changes but also the solar system's journey through the Milky Way galaxy.
Was the sky during the dinosaur era a different colour from today's blue?
The sky we see today is blue because of Rayleigh scattering. Sunlight contains all the colours of the spectrum, but shorter wavelengths, like blue and violet, scatter more when they hit air molecules.
Our eyes are more sensitive to blue than violet, which is why the sky appears blue.
However, during the time of the dinosaurs, which lasted for about 250 to 65 million years ago during the Mesozoic Era, Earth's climate and atmospheric conditions were quite different. Earth was generally warmer during this era, which meant more water vapor in the air. This didn't necessarily mean more clouds, since cloud formation depends on evaporation and saturation levels, but it could have impacted how the sky appeared.
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This means that while the physics of Rayleigh scattering still applies, the exact appearance of the sky may have shifted due to changes in humidity, temperature, and atmospheric particles. Closer to the end of the Mesozoic, it likely resembled the nearly-clear light blue skies we know today.
The night also looked different than today!
The sky's appearance also changed depending on where Earth was in the Milky Way galaxy. According to NASA scientist Jessie Christiansen, when dinosaurs such as Stegosaurus and Iguanodons roamed Earth during the early Cretaceous period, "our entire solar neighborhood was on the opposite side of the Milky Way galaxy that it is now."
Christiansen explained that "the dinosaurs were around for 200 million years, give or take, so the sky might have looked different early on but more like today towards the end, about 65 million years ago," as reported by CNN.
It is never possible to reach the same point that the Earth travelled years ago!
Apart from that, Christiansen also said that "we're back to where we were between 200 to 250 million years ago" in terms of our position within the galaxy. But because everything in the galaxy, including stars and solar systems, is constantly moving and rotating around a central black hole, she clarified that "we've never really [been] back at the same absolute point in space because it's not possible."
So, was the sky a different colour back then?
The answer is probably yes, at least for some time. While it may not have been of a starkly different colour but probably of a slightly different shade of blue as per some reports. While the scattering of light works the same, Earth's shifting climate, atmosphere, and cosmic position likely made the sky appear a bit different at various points in dinosaur history.
Photo: Canva
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