Corallis

Seas · Oceans

5 whys told, 3 on video

ocean
fish
waves
depths
diving

Start with the most surprising

The whys of this universe

A stretch of wet sand seen from above: a small elongated blue-violet pouch lying flat, and long fine threads running from one end of it across the whole lower half of the frame.

Oddity
Video 51 s
4 min

Why does a beached Portuguese man o' war still sting?

The sting depends on neither the animal's life nor its will: each cell is a pre-loaded mechanism that fires on contact, even weeks after beaching.

Three hearts and copper instead of iron: the octopus is built for cold water, and its blue blood flows under the sea.

Oddity
3 min

Why do octopuses have three hearts and blue blood?

Three hearts, copper instead of iron, and one heart that stops the moment it swims. The octopus solved a problem our own blood gets around another way.

As a wave moves into shallow water it slows down. Arriving at an angle, one end brakes before the other, the wave pivots and ends up facing the beach.

Video 35 s
4 min

Why do waves always arrive parallel to the shore?

Rain dissolves the rocks, rivers carry the salt down to the ocean, the water evaporates, and the salt stays behind.

Video 29 s
3 min

Why is the sea salty?

Seawater holds about 35 grams of salt a litre, the Baltic under 10, the Dead Sea more than 340. Each sea keeps what the rivers bring and the Sun leaves behind.

The Moon pulls the sea harder on one side of Earth than the other. The ocean stretches into two bulges that the planet rotates through each day.

3 min

Why are there tides?

High tide at 9 a.m. today comes back around 9:50 tomorrow, because the Moon keeps moving. In the Bay of Fundy, a funnel coast stretches the tide to 16 metres.

Newsletter

One why every Sunday, in your inbox.

Shh: Quaé is sleeping until the next why, Sunday morning.

Corallis on video

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Corallis is the salt expanse that breathes twice a day. Here you learn why there are tides, why the sea is salty, and why waves always arrive parallel to the shore. Beneath that water runs almost everything you read online, too, through cables laid on the floor.

Science · Body · Tech

Lumera

The universe next door

LumeraScience · Body · Tech

Lumera is the glass-domed city where microscope meets computer. Why do we dream? Why do screens run warm? Answers get worked out here, without the jargon.

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