Why do stars twinkle?
Imagine a summer warm night and clear sky covered with thousands of blinking star diamonds. Very romantic and beautiful, but do you know why they actually blink? It happens because the Earthly atmosphere is warmed-up inhomogeneously.
Warm and cold air has different density, that's why the deflection angle of the light is also different when it is going through warm or cold atmospheric layers. Airflows are constantly moving and mixing, thus combination of cold and warm layers being always changed. As a result, a star may seem very changeable – first it may be bright and the next moment obscure. Sometimes it may even seem that a star is twitching. When viewed at high magnification a star may seem to change its shape and color.
Stars twinkle a lot right after the sunset, because a great number of warm airflows rise up into the atmosphere from the earthly surface that is warmed-up during the daytime.
Time flies. The first half of the 21st century is going to end in about 30 years! As it turns out, even now we can predict some important events that are going to happen until 2050... QuizzClub team wants to tell you about the most interesting of them today.
The Dead Sea keeps people alive 9/21/2017 • Stephanie Nixon
Actually the Dead Sea is not a sea - it's a lake. The lake is landed between Jordan, Israel and Palestine. Its surface is 430 meters below the sea level. The water has a unique chemical composition and is extremely salty: a man can read a newspaper while sitting in the middle of the Dead Sea without effort. Moreover, the Dead Sea is famous for its healing qualities. We provided the info about the healthy influence of the lake on a person. Come and see!
The world under the microscope seems magical. We bet you won't recognize these objects you see every day at once. Watch and enjoy!
Our natural satellite plays an important part in the lives of all humans - we believe that the Moon has a certain influence on our mood, health and even destiny. But some things about the Moon are still little-known and, of course, there are some myths to be exploded...
Annually hundreds of tropical cyclones, tornado cyclones, hurricanes and sandstorms appear on Earth. We obtain disturbing messages about disasters all over the planet from the TV or radio. Have you noticed those destructive creatures always have feminine names? It may seem quite absurd, that is why we decided to clarify the matter for our dear readers!