by Jesse L.

What is a Nebula

A nebula is a thick cloud of dust and gas between stars. Nebulae are made of mostly light elements like hydrogen and helium. That's because of the gas component of nebulae. Nebulae are also partially made up of heavier elements like oxygen and iron. The heavier part is because of the dust component of nebulae.

Image of a Nebula

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The Science of Nebulae

When clouds of dust in the universe collapse a star's core forms and that expels gas so that it collects with the remaining dust to form a nebula and a new star. On a bigger scale of time dark matter (what the universe is made of) created the big bang which helped make stars form which helped nebulae form. So basically nebulae have formed because of dark matter. Next when you see the spiral arms of a galaxy those arms are nebulae. Now some nebulae are brighter than others and some are darker than others. The brightness of a nebula depends on how many stars it has and how hot those stars are.

Famous Nebulae

One of the most famous nebulae is the Andromeda Nebula. The Andromeda Nebula's discovery was credited to Edwin P. Hubble even though he most likely wasn't the first to discover it . In 1923 Edwin P. Hubble discovered that it had faint stars which meant it was a galaxy. Not to long afterward it was proven to be the closest galaxy to the Milky Way. In the end the Andromeda Nebula is a very famous nebula.

Next, the Crab Nebula is another famous nebula. The Crab Nebula is so bright because of it's stars. At the core of the nebula is a neutron star. The neutron star gives off radiation. This radiation excites the electrons in the nebula so that they spin at almost the speed of light which gives the nebula it's bluish glow in the center. Finally, the Crab Nebula is a very interesting nebula.

Another famous and interesting nebula is the Trifid Nebula. The Trifid Nebula is 5,400 light-years away and was discovered by Charles Messier in 1764. There are hundreds of new stars in it and they light it up brightly. It has so many stars that it has even been called a star nursery by some. In conclusion the Trifid Nebula has some cool qualities that make it famous.

Lastly, the Butterfly is a very interesting Nebula. The Butterfly Nebula is the remains of a dead star that was five times the mass of the sun. The star's outer layer was expelled 2,200 years ago which is what the glowing gas in the nebula is. The nebula is over two light years from one end to the other which is equal to half of the distance from the sun to the nearest star. The Butterfly Nebula's shape resembles a butterfly which is why it is called the Butterfly Nebula. Clearly, the Butterfly Nebula's unique shape makes it stand out so it's famous.

Image of The Butterfly Nebula

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Image of the Andromeda Nebula

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What is a Nebula? Astronomy and Space for Kids - FreeSchool