MYSTERIES WONDERS AND AMAZING THINGS OF THE WORLD

The deepest known point of planet Earth in Mariana Trench which is located in western Pacific Ocean. The maximum known depth was measured as 10,994 meters (36070 feet) at a small slot-shaped valley in its floor commonly known as Challenger Deep. At the bottom of the trench water pressure increases to 15,750 psi (1,086 bars) i.e. 1000 times the standard atmospheric pressure at sea level. This intense pressure increases the density of water by 4.96%. This implies that 95 liters of water at the depth of Mariana Trench would contain the same mass as 100 liters at the surface.  INTERESTING FACTS: As the Earth in not a perfect sphere, the seafloor of this trench is not closest to the center of the Earth.   If Mount Everest was placed in Mariana Trench, its pinnacle would still be over 1.6 kilometers (1 mile) from the surface of water. 

Frederick Valentich, a 20 years old pilot disappeared while on a 235 kilometers (125 mile) training flight in a light aircraft (Cessna 182L) over Bass Strait in Australia on 21 October 1978.  Valentich communicated to Melbourne Flight Service to report an unidentified aircraft which was following his aircraft at 4,500 feet. He was told by air traffic control that there was no known aircraft flying at that level. Valentich said he could see four bright landing lights but was unable to confirm its type. He reported that it had passed about 1,000 feet overhead and was moving with high speed. He was of the opinion that some other pilot is playing games with him when the unidentified aircraft approached him from the east. Valentich said that aircraft was orbiting above him and that it had a shiny metal surface and a green light on it. Valentich then reported that he was experiencing engine problems. When he was asked to identify the aircraft, Valentich replied, "it is not an aircra