APOD: A Full Plankton Moon (2024 Mar 11)

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APOD: A Full Plankton Moon (2024 Mar 11)

Post by APOD Robot » Mon Mar 11, 2024 4:06 am

Image A Full Plankton Moon

Explanation: What glows in the night? This night featured a combination of usual and unusual glows. Perhaps the most usual glow was from the Moon, a potentially familiar object. The full Moon's nearly vertical descent results from the observer being near Earth's equator. As the Moon sets, air and aerosols in [url=https://climate.nasa.gov/news/2919/eart ... ered-cake/" >Earth's atmosphere</a> preferentially scatter out blue light, making the <a href="ap220515.html]Sun-reflecting satellite[/url] appear reddish when near the horizon. Perhaps the most unusual glow was from the bioluminescent plankton, likely less familiar objects. These [url=https://en.wikipedia.org/wiki/Plankton# ... ankton.jpg" >microscopic creatures</a> glow blue, it is thought, primarily to <a href="https://assets-global.website-files.com ... %20Dog.jpg]surprise[/url] and deter predators. In this case, the glow was caused primarily by plankton-containing waves crashing onto the beach. The image was taken on Soneva Fushi Island, Maldives just over one year ago.

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Re: APOD: A Full Plankton Moon (2024 Mar 11)

Post by Ann » Mon Mar 11, 2024 5:23 am

Fantastic colors!

That's a gorgeous "Moon reddening sequence", as the Moon is seen to sink - vertically! - towards the horizon through thicker and thicker layers of atmosphere (and likely clouds). It is, in a way, a picture-perfect illustration of why stars get reddened when there is interstellar dust between us and them.

Of course, the color of the plankton is just jaw-dropping. Particularly when you consider the contrast between the ochre-colored sand, the strikingly cyan-green ocean and the "neon blue" plankton.

I have been swimming in bioluminescent plankton myself, off the coast of Gothenburg at 57o north, but it wasn't as neon blue as the it is in the APOD. It was more blue-white. The video below shows bioluminescent plankton off the coast of Strömstad, at latitude 56.58o north:

Click to play embedded YouTube video.

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