About 1,000 to 2,000 feet in the sea is a place where only blue beams in sunlight can penetrate. This is the home of the swell shark and chain catshark.

Look at them with your human, land-ready eyes, and all you’ll see are fish spotted in brown, beige and gray. But peer through a blue filter, more like the way these sharks see each other, and behold beaming beauties robed in fluorescent green spots.

In a study in iScience, researchers revealed how they can transform into a neon sign: Molecules inside their scales transform how shark skin interacts with light, bringing in blue photons, and sending out green. This improved understanding of these sharks’ luminous illusions may lead to improvements in scientific imaging. “I think this is just yet another amazing feature of shark skin that we didn’t already know about — just adding to their list of superpowers,” said David Gruber, a marine biologist and an author on the paper.

Where lava flowed, crater lake likely rises

Last spring, Hawaii’s Kilauea volcano began its most destructive eruption in recorded history. On May 2, as its underlying magma supply headed to the mountain’s lower east rift zone, a lava lake within the Halema’uma’u summit crater that had been there for 10 years began to rapidly drain. A week later, this pool of molten fury had vanished.

Now, the lake is being replaced by water that is likely rising from below. A single green pool was spotted at the base of the crater in late July. As of now, there are three pools, each growing in size and likely to coalesce. Only time will tell, but it’s possible that this is the birth of a full-blown crater lake in a pit once ravaged by fire.

Weather nerd alert: NOAA has new app

The National Oceanic and Atmospheric Administration is best known for its satellites, weather forecasting and scientific explorations. But that doesn’t mean the public can’t get in on the fun.

A new smartphone app, SOS Explorer Mobile, lets viewers play with an animated globe and some of NOAA’s most fascinating facts. You can zoom in, adjust and even make the globe spin as you see the world through different lenses.

The app, available free on Apple and Android devices, is like a miniature portal into one of the world’s most robust collections of scientific information.

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