Why this huge energy consumption?
To overcome the planet's gravitational field and allow a ship to travel in outer space
All bodies around the globe are attracted to Earth, the force of attraction called the gravity and acceleration with which these bodies attracted into the gravitational field is called gravitational acceleration g = 9.81 m/ s ².
Speed needed to escape Earth cosmic ship is 11000 m / s and can be done with an amount of energy of 2,400 tons of fuel
Escape speed from Earth's surface is called the second cosmic speed.
With this speed of a ship lifts off from Earth's surface and escapes the planet's gravitational field.
Gravitational acceleration surface of Mars is g = 3.75 m / s ² and have an escape speed of 5100 m / s which is equivalent to a fuel quantity of 1055 tons
For a trip to outer space or on Mars was built a Kennedy Space Center, a spaceship and made available energy 2400 tons of fuel - liquid oxygen and to overcome the gravitational field of Mars that has g = 3.75 m / s ² and to return to Earth we need a space center, a spaceship and an energy of over 1055 tones of fuel - liquid oxygen