The International Space Station is a habitable satellite built with the cooperation of 16 countries.
This bizarre-looking fish uses its bioluminescent lure to catch its prey. The animation explains how it works.
The pancreas and the liver empty digestive juices into the duodenum.
Space probes and Mars rovers examine the structure of Mars and possible traces of life.
Tsunami waves are very high waves of immense destructive power.
Lateral compressive forces cause rocks to form folds. This is how fold mountains are formed.
The rise and drop of sea levels caused by the gravitational force of the Moon.
Carbon is bound in organic substances during photosynthesis, while during breathing, it is released into the atmosphere.
Dry land on the surface of Earth is divided into continents which are separated by oceans.
Tectonic plates can move in relation to each other.
Vertical forces can break up layers of rock into fault blocks, which then move vertically along the fracture planes.
The theatre that has a distinctive shape and excellent acoustics was situated at the side of the Acropolis in Athens.
Human blood consists of blood cells and plasma.
Water on Earth is in a continuous state of change. The water cycle includes processes such as evaporation, precipitation, melting and freezing.
This animation demonstrates the development of the human embryo and foetus.
The centre of the Indian mausoleum complex is a white marble tomb built by Shah Jahan for his beloved wife.
Soviet labour camps (Gulags) were located far from inhabited areas.
Located in the Grand Mosque of Makkah, the Kaaba shrine is the most sacred site of Islam.
Lunar eclipses occur when the Moon passes through the shadow cone of Earth
The curvature of the lens of the eye changes when we look at a distant or at a near object, to ensure a sharp image.