Olympus Mons is considered to be the tallest planetary mountain in the Solar System. It is not located on Earth. Rather, it is located on the planet Mars.
Olympus Mons was discovered by the Italian astronomer Giovanni Schiaparelli in the late 19th century. He was able to observe the mountain from Earth using an 8-inch telescope.
Olympus Mons is considered to be a large shield volcano. A shield volcano forms as lava flows out of the ground and spreads outs. It creates a low, squat volcanic structure.
According to NASA, Mons Olympus reaches a height of over 40 km from base to summit. It is almost three times higher than Mount Everest's height above sea level.
Its base is as large as the area of the state of Arizona with a diameter of more than 600 km.
The summit caldera of Olympus Mons is 3 km deep and measures 80 km across. The volcano lies in a large volcanic region on Mars' surface. Images of the volcanic mountain show that there are numerous thin lava flows on its upper slopes.
Scientists believe that Olympus Mons grew so large because of the low gravity, the slow-moving tectonic plates, and high volcanic activity on Mars. They also believe that the volcano is only several million years old and is still active that it could erupt again. The most recent volcanic eruption at Mons Olympus is estimated to be 25 million years ago.