Popularizing natural science knowledge is the crucial part of quality education, which it may help us to understand and cognize this objective world, which prompt everyone to discover the society and life by using scientific perspective. In addition, scientific knowledge in nature may help us far away from ignorance. Meanwhile a lot of natural phenomenons is very simple and common to know, but we never know why this phenomenon is occurred. Based on this reason, learning related necessary natural science knowledge is very important.
Why star shine?
We see the stars shining, not because of the changes in the light of the stars themselves, however it is about the shade of the atmosphere. The atmosphere is separated between earth and the stars, and when starlight passes through the atmosphere, it is affected by the density and thickness of the atmosphere. The atmosphere is not absolutely transparent, its transparency will vary according to the density. So when we look at the stars through the ground, we will see the stars to be flashing.
Why is sea water mostly blue and green?
Looking to the sea,the most often we found that the sea appears blue and green. But when you pick up the sea water, you can only see it like the water of the past, transparent and colorless. It turns out that the sea itself is not much different from the water we touch everyday, and it is also transparent. The green we see is actually the phenomenon of seawater’s ability to absorb light, then when the sea is deeper and the green light is also absorbed, the sea looks blue.
Why do leaves turn into colors?
The reason of leaf discoloration is related to its chlorophyll, a chemical substance. When autumn comes, the day is shorter than the summer, but temperatures are relatively low, so the leaves stop producing chlorophyll, the remaining nutrients transport to the trunks and roots as storage. Leaves lack green chlorophyll, and other chemical pigments appear at the same time, so we see more yellow and brown leaves at the autumn.