5D Andrew Stars

A star is  born by a huge cloud of gases and star dust called  a nebula. A nebula is when a star dies and new stars will be born from the gases of the old stars that died. Gravity pulls clumps of gas together and the gases get very hot and get so hot that they cause a nuclear reaction and turn into stars. Clusters of stars can be from just a handful of stars to hundreds and hundreds of stars. When stars are born in clusters they call this a stellar nursery.

Once new stars are formed, a cluster of young stars leaves the nursery and the hot gases from those stars help cause more new stars to be born in the original nursery. Then, the first stars spread out even more and get farther from the nebula and the ones that just formed continue with the cycle that just keeps going on and on.

Star Formation Stars form from collapsing clouds of gas and dust. As the cloud collapses, its density and temperature increase. The temperature and density are highest at the center of the cloud, where a new star will eventually form. The object that is formed at the center of a collapsing cloud, and which will become a star, is called a protostar. Since a protostar is embedded in a cloud of gas and dust, it is difficult to detect in visible light. Any visible light that the protostar emits is absorbed by the material surrounding it. Only during the later stages, when a protostar is hot enough for its radiation to blow away most o

f the material surrounding it, can it be seen in visible light. Until then, a protostar can be detected only in the infrared.

As the collapse proceeds, the temperature and pressure within the globule increases, as the atoms are in closer proximity. Also, the globule rotates faster and faster. This spinning action causes an increase in centrifugal forces (a radial force on spinning objects) that causes the globule to have a central core and a surrounding flattened disk of dust (called a protoplanetary disk or accretion disk). The central core becomes the star; the protoplanetary disk may eventually coalesce into orbiting planets, asteroids, etc.

The contracting cloud heats up due to friction and forms a glowing protostar; this stage lasts for roughly 50 million years. If there is enough material in the protostar, the gravitational collapse and the heating continue.

The Eagle nebula, a stellar nursery illuminated by ultraviolet light which is emitted from the newborn stars. Stars are formed in nebulae, interstellar clouds of dust and gas (mostly hydrogen). These stellar nurseries are abundant in the arms of spiral galaxies. In these stellar nurseries, dense parts of these clouds undergo gravitational collapse and compress to form a rotating gas globule.