Animals that evolved in cold parts of the world usually have lighter skin. If a light-skinned animal has blood vessels close to the surface of their ear skin, this will make the ears look pink.
Flight Engineer Peggy Whitson suits up ahead of a spacewalk. Vomiting inside a spacesuit during a spacewalk could be fatal for astronauts.
NASA
When humans are happy, they may smile, or laugh, or dance - but what do animals do? Melissa, age 12, wants to know how she can tell if her cat is happy and likes you.
The mass of the Earth is big enough that the gravitational force it creates can pull the hard shape of ice, rock and metal into a sphere.
NASA Earth Observatory images by Joshua Stevens, using Suomi NPP VIIRS data from Miguel Román, NASA's Goddard Space Flight Center
Imagine the Earth pulling everything it is made up of, all of its mass, towards its centre. This happens evenly all over the Earth, causing it to take on a round shape.
Scientists usually use the word “venomous” rather than “poisonous” when they’re talking about snakes.
Flickr/Sirenz Lorraine
Bees sting other animals, including humans, when they think there might be a threat to their hive. But Evie, age 8, wonders if bees ever accidentally sting other bees.
Dreams are like a forest walkway: there’s no clear sense of direction and you can easily get lost.
ollierb/flickr
Niamh, age 7, wants to know why we have scary dreams. But after 200 years of study, dreams are still very much a mystery.
Lasers being shone from the European Southern Observatory’s Very Large Telescope in Chile.
These lasers help remove the twinkles in the night sky and help astronomers see stars clearer on Earth than ever before.
F. Kamphues/ESO
Jake Clark, University of Southern Queensland; Belinda Nicholson, University of Southern Queensland; Brad Carter, University of Southern Queensland, and Jonti Horner, University of Southern Queensland
How exactly do the stars twinkle in the night sky? As it turns out, the answer is full of hot air… and cold air.
Rainbows get their round shape from a process called reflection.
Flickr/Luigi Mengato
Breathing in through your nose has many medical benefits over mouth breathing. As usual, be wary of misinformation and bias when looking up health on the internet.
Big sewer pipes take all sewage to a place where it is treated. This place is called a sewage treatment plant.
Flickr/Dean Hochman
The way humans make an ‘ssss’ noise is different to the way a snake does it. We put our tongue behind our teeth when we hiss, but for a snake the tongue isn’t involved at all in making sounds.
The Sun is currently middle-aged, having celebrated its 4,568,000,000th birthday at some point in the last million years.
Flickr/ChopWood CarryWater
What caused the Big Bang is still a mystery. And that’s just one of the many unanswered questions, in spite of everything we do know about the birth of the Universe.