Underground waters

Groundwater and aquifers are types of underground waters.

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Solar eclipse and lunar eclipse

We can observe quite interesting astronomical phenomena when the Earth, the Sun and the Moon align.

Coal formation

This video presents the different stages of coal formation.

Milky Way

The diameter of our galaxy is about 100,000 light years; it contains more than 100...


The last Ice Age ended about 13 thousand years ago.

Volcanic activity

The area surrounding an inactive or extinct volcano is not necessarily calm. Let’s see the...


Rocks are a composed of minerals. These minerals can often be found in their pure forms.

The process of physical and chemical weathering

Upon physical weathering the rock only falls into pieces, whereas during chemical weathering its...

The Pompeii before time

There is a little village in Northern Hungary in Central Europe that is a hiding place for a...

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