Sunlight: World’s most ancient traveller

Sun, the pivotal element of the solar system, is a middle-aged star that is around 4.6 billion years old. This near-perfect sphere is made up of 70 per cent hydrogen and 28 per cent helium. With the amount of hydrogen left on it, it can survive for another 5 billion years. In the last stages of its life, it will begin burning helium. In this phase, the sun will grow in size and eventually consume Mercury, Venus, and Earth, till its collapse. Although the mass of the sun will remain the same after the collapse, its volume will reduce to about the earth’s current volume.

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‘Fire rainbows’ are created from ice!

‘Fire rainbows’, technically known as circumhorizontal arcs, occur from a spectacular phenomenon in the sky. They are formed by the refraction of sunlight or moonlight on plate-shaped ice crystals in the clouds high up in the sky. They are neither fire nor rainbow, yet are called so because of the vibrant colours that spill out in different directions making them appear like flames.

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