Are you dreaming that you’re awake or are you living in a computer simulation? There might be no way to be sure.
Sometimes air goes up past the condensation level then falls back below the condensation level, then up, then below, again and again. This creates clouds that are stripy, often with lines between the clouds.
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Clouds formed by rising warm air currents are called ‘convection clouds’. Because of all the rising air coming up, these clouds can be bumpy on top, sometimes looking like cotton wool or cauliflower.
Andrew Pontzen, Fabio Governato/Wikimedia Commons.
We are in the Milky Way. If you travelled on an extremely fast spaceship for more than two million years, you would reach our neighbour, the Andromeda galaxy. All other galaxies are even further away.
Inside the pupa (or chrysalis), the caterpillar actually turns to liquid as it transforms into a butterfly or moth.
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Scientists were not sure if an adult butterfly could remember things it learned as a caterpillar. Then a study by a team of US scientists found something very interesting.
Waves lap against the shore on the south coast of England and the North coast of France – but the answer to this puzzle is in the wind and the land, not the waves themselves.
Blue whales are the largest creatures to have ever lived on Earth.
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Tonsil tissue is particularly important in the first six months of life. After this, our lymph glands take over most of the work and the tonsils are essentially out of a job.
If you discovered a new type of dinosaur, what would you name it?
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We know of about 900 valid dinosaur species that existed. ‘Valid’ means scientists know the dinosaur from enough of the skeleton bones to feel pretty sure that it differs from other known dinosaurs.
Plastic bags are commonly mistaken for food by sea animals. They require a lot of energy and resources to be made, and have caused floods in some countries.
Even if mermaids aren’t real, they’ll likely feature in human stories for many years to come. Very few mythical creatures are found in so many diverse cultures, across so many years without changing.
SIM cards link accounts to handsets. They keep communications private. They store messages. Although small and simple, they are a big part of modern mobile phone systems.
Some explosive volcanoes can send ash high up into the sky and it can travel around the world over different countries.
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When magma rises towards the surface gas bubbles start to form. Whether or not they can escape as the magma is rising affects how explosive the eruption will be.
If the insect wants to stay right in front of your nose, it must fly forwards just a little bit when the car is speeding up. But when the car is at constant speed, it only needs to hover.