SOLAR SYSTEM

Detailed explanation-1: -The dust and gases in a nebula are very spread out, but gravity can slowly begin to pull together clumps of dust and gas. As these clumps get bigger and bigger, their gravity gets stronger and stronger.

Detailed explanation-2: -Approximately 4.6 billion years ago, the solar system was a cloud of dust and gas known as a solar nebula. Gravity collapsed the material in on itself as it began to spin, forming the sun in the center of the nebula.

Detailed explanation-3: -The force that keeps them apart is the electromagnetic force. However, if you can get two protons close enough together, suddenly they are attracted VERY strongly by a new force, called the strong force.

Detailed explanation-4: -Star-Forming Nebula These knots contain sufficient mass that the gas and dust can begin to collapse from gravitational attraction. As it collapses, pressure from gravity causes the material at the center to heat up, creating a protostar. One day, this core becomes hot enough to ignite fusion and a star is born.

Detailed explanation-5: -Outward pressure balances the inward pull of gravity and keeps the cloud from collapsing. 1) Gravity causes the particles to attract. 2) Particles move closer and collisions cause pressure to increase and particles are pushed apart. 3) Inward force of gravity is balanced by outward pressure and nebula becomes stable.