The NGC7293 Helix Nebula is a large planetary nebula located in the constellation Aquarius.

Spaceweather reports that the solar wind has damaged the Earth's magnetic field. The magnetic field plays a major role in protecting the ozone layer and life on Earth from harmful cosmic rays and radiation. The Earth's magnetic field is threatened...

February 7, 1984. Everyone in NASA's mission control room is out of breath - out of control, Bruce Macandoules walks into space! This is the first time in history that a self-designed MMU control system has been used for space...

Look at the two pictures given to make this clear. The first is when someone throws a stone. The velocity of the stone is shown as two elements, vertical and horizontal. Since there is no force in the opposite direction...