d:diving

It’s a bird, it’s a plane – it’s a manta ray! Flower Garden Banks National Marine Sanctuary visitor Chas Downey was diving on the sanctuary’s West Flower Garden Bank when this manta ray came swimming by. What an amazing sight!

Manta rays are popular visitors to the sanctuary, and there are still many unanswered questions about these enormous rays. Sanctuary researchers are working to find out more using acoustic tags. 

(Photo: Chas Downey)

Life at Sea with Rodrigo Friscione

To see more of Rodrigo’s photography, follow @rodrigofriscione on Instagram.

Rodrigo Friscione (@rodrigofriscione) wasn’t born underwater, but it was close enough. His father owned a dive shop in Cancún, Mexico. “As long as I can remember, I was surrounded by diving — tanks, boats, gear, fish, all of it,” the 32-year-old photographer, who still lives in Cancún, says. Rodrigo works for Pelagic Life, a Mexican organization focused on protecting the high seas. “Most of our efforts center on shark fishing, because sharks are on the brink of extinction; they are a representative species of oceans worldwide.”

On a family trip to the Galápagos in 2003, Rodrigo started playing around with a camera, and he’s documented his underwater adventures since. His photos offer a breathtaking view of the wildlife beneath the crystal-clear waters of the Pacific. “My favorite subjects are marine mammals, they are incredibly smart and they interact with you when you are underwater,” he says.

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Diving is a popular event for spectators, but it can also be rather confusing. We know that divers are rewarded for minimizing their splash, but what exactly does that mean and how do they do it?

The ideal water entry, called a rip entry by divers, requires a diver to hit the water in a vertical orientation with their arms braced and palms held flat over their head. Striking the water tears open a cavity for the athlete’s body to enter. To minimize splash, the diver wants to fall into this expanding cavity without striking the sides, which would throw up an additional splash. This is the reason for vertical entry. Hand position is also important. If the athlete were to point their fingers, they would create a narrower cavity and larger splash.

After the athlete enters the water, the cavity closes off under the surface and the water rebounds in a splashy Worthington jet. For the speed and size of human divers, this later splash is essentially unavoidable. What the commentators don’t really tell you, though, is that diving judges are only supposed to judge a diver’s entry up to the point that their feet go under the surface. They’re instructed to ignore everything that happens underwater and after entry. So that big rebound splash we all see isn’t meant to count! (Image credits: A. Pretty/GettyImages; kaorigoto, source)

Previously: Minimizing splash by being hydrophilic; the physics of skipping rocks and avoiding splashback at the urinal

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