At first, stars are formed from a cloud of dust and gas in space known as a nebula.
Even though stars are not alive, they have different stages of development such as
birth, development and death. Telescopes and satellites help us learn more about the
birth of stars, and they help us understand more about the universe. They show us
how much we really don't know about stars and their development.
Newborn stars emerge from dense, compressed pockets of evaporating gaseous
globules (EGGs). This gas is thick enough to fall down under its own weight. As the
cloud gets slighter, it begins to spin gradually faster, forming young stars. After
millions of years after the collapse, the center of the cloud reaches great
temperatures. At around 15 million Kelvin, the hydrogen nuclei of it fuse, and form
helium in nuclear fusion. The process releases huge amounts of energy in heat and
light forms, and so a star is born. Stars usually have enough hydrogen in it to power
it for billions of years. Stars continuously grow as the gather more mass from their
surroundings.
A protostar must reach about 10 million degrees Celsius for nuclear fusion to start in its core, triggering the transition into a true star. This marks the point where hydrogen atoms begin fusing into helium, releasing energy in the process. So, a protostar will become a full-fledged star after nuclear fusion begins at this temperature.
A newly formed protostar will radiate primarily in the infrared wavelength range. This is because the protostar is still in the process of contracting and heating up, emitting energy as thermal radiation at longer wavelengths as it evolves towards becoming a main sequence star.
A star is considered born when nuclear fusion begins in its core, creating energy and light. This process marks the transition from a protostar to a true star.
A protostar heats up internally as it contracts due to the gravitational potential energy being converted into thermal energy. The collapse of the gas cloud causes an increase in density and pressure, leading to a rise in temperature at the core. This process eventually triggers nuclear fusion and marks the start of a star's life cycle.
It becomes energy, hence the energy released in nuclear bombs.
Nuclear fusion. In the case of stars, it is often called nucleosynthesis.
A protostar is not in energy balance because it is still in the process of accumulating mass and contracting under gravity. This causes the protostar to release energy as it heats up, but it has not yet reached a stable state of equilibrium where the energy being released is balanced by the energy being generated.
The main source of energy during this stage is gravitational potential energy, as gas in the interstellar cloud collapses under gravity to form a protostar. The energy released from this gravitational collapse heats up the material and initiates the process of star formation.
A protostar must reach about 10 million degrees Celsius for nuclear fusion to start in its core, triggering the transition into a true star. This marks the point where hydrogen atoms begin fusing into helium, releasing energy in the process. So, a protostar will become a full-fledged star after nuclear fusion begins at this temperature.
The basic idea is that the protostar contracts, under the influence of gravity, until it gets dense and hot enough to undergo nuclear fusion. You can find more details at the Wikipedia article "Protostar".
The temperature of a protostar increases due to gravitational contraction. As the protostar contracts, potential energy is converted into kinetic energy, causing the particles to move faster and collide more frequently, resulting in an increase in temperature. This process eventually leads to the ignition of nuclear fusion and the star's main sequence phase.
As gravity collapses the cloud to form a protostar, the temperature and luminosity both increase. The increase in temperature is due to the compression of material, causing the protostar to heat up as energy is released. The increase in luminosity is a result of the protostar radiating this energy.
A protostar becomes a star when nuclear fusion begins in its core, converting hydrogen into helium and releasing energy. This process generates enough heat and pressure to balance the force of gravity, causing the protostar to shine brightly as a star.
A protostar is a collapsing cloud of gas and dust in the process of becoming a star, while a star is a luminous sphere of plasma held together by its own gravity and shining through nuclear fusion in its core. Protostars are still in the early stages of stellar evolution, while stars have reached a stable state of energy equilibrium.
A newly formed protostar will radiate primarily in the infrared wavelength range. This is because the protostar is still in the process of contracting and heating up, emitting energy as thermal radiation at longer wavelengths as it evolves towards becoming a main sequence star.
A contracting protostar converts gravitational energy into thermal energy through gravitational collapse. As the protostar shrinks in size, gravitational potential energy is converted into kinetic energy, causing the temperature and pressure in the core to increase. This process eventually leads to the ignition of nuclear fusion, where hydrogen atoms combine to form helium, releasing vast amounts of thermal energy in the form of light and heat.
trapping of thermal energy inside the protostar