SOLAR SYSTEM

Detailed explanation-1: -What happened in the protosun to make it into a Sun? Energy from collisions and pressure from gravity caused the center of the solar nebula to become hotter and denser. When the temperature at the center became hot enough-about 10, 000, 000 degrees Celsius-hydrogen fusion began.

Detailed explanation-2: -Gravity collapsed the material in on itself as it began to spin, forming the sun in the center of the nebula. With the rise of the sun, the remaining material began to clump together. Small particles drew together, bound by the force of gravity, into larger particles, according to the core accretion model.

Detailed explanation-3: -Gravity can pull some of the gas and dust in a nebula together. The contracting cloud is then called a protostar. A protostar is the earliest stage of a star’s life. A star is born when the gas and dust from a nebula become so hot that nuclear fusion starts.

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.

Detailed explanation-5: -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. Eventually, the clump of dust and gas gets so big that it collapses from its own gravity.