Day 8: Solving the green flash mystery
By Jamie Menzies
On the RV Investigator we get to see some particularly spectacular sunrises and sunsets.
Gases and particles in the Earth’s atmosphere cause light waves from the sun to bend, splitting it into different colours just like in a prism.
Blue light has the shortest wavelength so it is split or “scattered” more than other colours, which is why we see blue sky most of the time.
A group of Red-footed Boobies flying over the mast of the RV Investigator in front of a blue sky. Photo credit – Eric Woehler, BirdLife Australia.
As the sun sets, light has further to travel to reach our eyes, so we see longer wavelengths which appear as reds and oranges.
Orange, red and yellow sunset light over the starboard side of the RV Investigator. Photo credit – Jamie Menzies
As the sun begins to disappear from the horizon, the long red and orange wavelengths bend over your head so, if you are lucky and the air is free of disturbance (as it often is on the high seas…), you might just see a quick green flash lasting a couple of seconds at the sunset’s finale.
Green flash as seen from the RV Investigator. Photo credit – Eric Woehler (BirdLife Australia).
Lots of people don’t believe in the mysterious green flash, but the scientists and crew on the RV Investigator will tell you otherwise.