Go to:Originally posted by wolram
hi,i have two questions i hope you can ansewer.
what is the process that initiates star birth?
how does gravity focus on a single point,that attracts space debris to eventualy form a star?
The process of star birth, also known as stellar formation, involves the gravitational collapse of a large cloud of gas and dust called a nebula. As the cloud collapses, it heats up and begins to spin due to conservation of angular momentum. This spinning motion causes the cloud to flatten into a disc, with most of the material collecting in the center. Eventually, the temperature and pressure in the center become high enough to trigger nuclear fusion, and a star is born.
Gravity is the driving force behind star birth. Without gravity, the gas and dust in a nebula would not be able to collapse and form a star. As the cloud collapses, gravity also causes it to heat up and spin, as mentioned above. Gravity is also responsible for holding the star together and maintaining its stable structure throughout its lifetime.
Gravity has several effects on the process of star birth. First, it causes the cloud of gas and dust to collapse and form a disc, as described in the first question. It also determines the size and mass of the star that will be formed. The more massive the cloud, the stronger its gravity and the larger the resulting star will be. Additionally, gravity can cause regions of higher density within the cloud, leading to the formation of multiple stars in a single nebula.
While gravity is the main factor driving star birth, there are other factors that can influence the process. For example, magnetic fields can play a role in shaping the structure of the collapsing cloud. Also, the composition of the cloud, including the types of elements present, can affect the rate of collapse and the types of stars that will form.
The time it takes for a star to form can vary depending on the size and mass of the cloud, as well as other factors. Generally, it can take anywhere from a few hundred thousand to several million years for a star to form from a collapsing nebula. This is just a small fraction of the total lifespan of a star, which can range from millions to billions of years.