What is happening in the nebula?
When this happens, the dust and gas condense into giant clouds like the Orion Nebula seen in the pictures above. As they start to condense further, in some spots in the nebula, stars begin to form. Most Diffuse nebula contain mostly hydrogen with smaller amounts of helium, oxygen, sulfur, and other heavier elements.
Nebula Formation: In essence, a nebula is formed when portions of the interstellar medium undergo gravitational collapse. Mutual gravitational attraction causes matter to clump together, forming regions of greater and greater density.
- Don't panic, we've got another 7 billion years or so before the Sun becomes a red giant star. As you probably know, stars shine because they're converting hydrogen into helium in their cores through a process called nuclear fusion.
- As a ball of dust and gas contracts under its own gravity, it begins to shrink and its core begins collapsing faster and faster. Even still, these objects may glow dimly because the force of gravity causes them to continue shrinking, which releases energy in the process.
- The Sun is our nearest star. It is, as all stars are, a hot ball of gas made up mostly of Hydrogen. The Sun is so hot that most of the gas is actually plasma, the fourth state of matter. The first state is a solid and it is the coldest state of matter.
The size, shape and characteristics of nebulae may vary significantly because some are star nurseries and others are the remains of dead stars. Keep reading to learn more about dark nebulae, emission nebulae, reflection nebulae and planetary nebulae. Dark nebulae are found in areas that have no nearby stars.
- More strictly speaking, the word "nebula" should be reserved for gas and dust clouds and not for groups of stars.
- Globular Clusters.
- Open Clusters.
- Emission Nebulae.
- Reflection Nebulae.
- Dark Nebulae.
- Planetary Nebulae.
- Supernova Remnants.
- The time it takes for a nebula to collapse into a star and start the nuclear burning of its hydrogen into helium depends on the size of the star. For a star the size of the sun, it takes about 10,000,000 years to collapse. For bigger stars, it is a shorter time - as low as 100,000 years for the biggest stars.
- The first stage is when a nebula collects and makes a mass of gas and dust then it begins to contract under its own gravity. The second stage in the birth of a star is the protostar. The second stage in the birth of a star is the protostar.
In some nebulae, stars form out of large clouds of gas and dust; once some stars have formed inside the cloud, their light illuminates the cloud, making it visible to us. These star formation regions are sites of emission and reflection nebulae, like the famous Orion Nebula shown in the picture on the right.
- The largest stars, in contrast, will be cool supergiants. Case in point, VY Canis Majoris is only 3,500 Kelvin, and a really big star would be even cooler. At 3,000 Kelvin, Humphreys estimates that cool supergiant would be as big as 2,600 times the size of the Sun.
- Stars are made of very hot gas. This gas is mostly hydrogen and helium, which are the two lightest elements. Stars shine by burning hydrogen into helium in their cores, and later in their lives create heavier elements.
- In some nebulae, stars form out of large clouds of gas and dust; once some stars have formed inside the cloud, their light illuminates the cloud, making it visible to us. These star formation regions are sites of emission and reflection nebulae, like the famous Orion Nebula shown in the picture on the right.
Updated: 7th October 2018