Introduction
Stars are spheres of plasma and mostly hydrogen. They have a mother, which they are made out of her. There are many different types of stars. Massive stars create force fields. Some stars hang around each other in big groups. There are stars that are intergalactic. Some stars are far out!!!!!
What is it?
It is made out of plasma. Plasma is ionic gas; it is the 4th state of matter. It has several layers, @ the core hydrogen atoms are turned into helium atoms. This is called nuclear fusion. Because of this stars produces light and heat. Many other electromagnetic waves are produced by it as well. They have different colors based on temperature. The hottest stars are blue. The 2nd hottest is white and the coolest is red. Some stars are very massive, while others not so much. They have absolute and apparent brightness. Absolute is how bright it would be 36 light years from Earth. Apparent is how bright it is from Earth. Most stars are binary: 2 stars orbiting each other. The elements beyond lithium was created by massive stars exploding. It is called nucleosynthesis.
Vega: It was my favorite star, because it's big and blue. It was the north star in the past and it may become that again in 12,000 years. It is 25 light years away in the Lyra constellation. It is a very young star: it is only 450 million years old. It has an asteroid belt and possibly planets.
Sirius: It has the most apparent brightness; it is 25 times brighter than the Sun. It is apart of Canis Major, which is is about 9 light years away. It has a companion or two.
Betelgeuse: It is a red supergiant star and it will go supernova soon. It is only about 637 light years away and it is apart of the Orion constellation. It is a rogue star or something like that. No one knows its birthplace.
Polaris: It is the current north star. It is a white supergiant and about 600 light years away.
Rigel: It is a blue supergiant and apart of the Orion constellation. It may have 3 companions. One day it will go supernova and become a neutron star or a black hole. It has a short lifespan because it so massive. It's a little baby: it is only 8 million years old.
Nebula
They are the mothers of stars. They come from from massive stars exploding or gases in outer space. It is made up of hydrogen, helium, dust, and plasma. Stars form when parts of the nebula collapse due to gravity and reach a very high temperature.
Horsehead: It is part of the Orion Molecular Complex. There are stars and planets that are being born there. It is only 1,375 light years away. Low-mass stars are being formed in the head.
Rosette: It is 5,000 light years away and 130 light years in diameter. This nebula is 10,00 times more massive than the Sun. It has about 2,500 baby stars.
Orion: It is the brightest nebula from Earth and 24 light years long. Planets, stars and brown dwarfs are forming in this nebula. It has about 700 stars in it.
Eagle: It has about 8100 stars and 5,700 light years away. It is 2 million light years long and 10 light years wide. There is a star there that 80 times as massive as the sun and 1 million times brighter.
Pelican: It is 1,800 light years away. There are many young stars there. It is part of North America Nebula.
Carina: It is 8,500 light years away. It has 2 open clusters and has the biggest star ever studied. Eta Carinae are 2 massive stars that orbit each other. They are 200 times more massive than the Sun and 5 million times brighter. They are the only known stars to emit ultraviolet lasers.
Tarantula: This is the greatest starburting region in the Local Group. It is in the Large Magnetic Cloud. It has a open cluster that may become a globular cluster, because it's so massive. A supernova was seen there in 1987. A neutron star was left after that.
Crab: Chinese astronomers seen the supernova that became this nebula. It has a pulsar @ the center and it is 6,500 light years away.
Main Sequence Star
They are the most common stars in the universe. The Sun is a main sequence star. The core makes the star want to explode and its gravity makes it want to implode. This balance keeps a star from dying. Eventually it runs out of fuel and becomes a black dwarf. Unless it is very massive, then it becomes a neutron star or a black hole. But before that happens it goes supernova. A supernova is a star explosion: there are 2 types. 1. A massive star blows up. 2. A big star takes material from a smaller star and then blows up. Some stars swell up later in life into a red giant. This will happen to the Sun. Stars that aren't uber massive becomes white dwarf right b4 they die.
Planetary Nebula
This comes from very massive stars when the core heats up. The energized core causes the the outer layers to expand. The various layers become like a force field. The core becomes a white dwarf star.
Ghost of Jupiter: It is 2 light years long and was formed 1,500 years ago.
Southern Owl: It is 4 light years in diameter. It is 2,030 light years away.
Blue Planetary: It is very bright and 4,900 light years away. This nebula is so bright the central star can't be seen in visible light.
Butterfly: The central star there is very hot. There is plasma on both sides of the star that look like wings. It has water ice, quartz, and crystalline silicates.
Blue Snowball: It is 1,800 light years away. The radius is about 1 light year.
Clusters
Globular: A group of sibling stars that are bound together by gravity. They are very ancient and each cluster may contain thousands or millions of stars.
Pyxis: It is about 14 billion years old and it 130,000 light years away. It may be from the Large Magellanic Cloud.
Terzan 1: It is 20,000 light years away and lives in our own backyard. It gives off a lot of X-rays.
M54: It is 87,000 light years away in the Sagittarius Dwarf Galaxy. It is 150 light years wide and 850,000 times brighter than the Sun. It has a black hole @ its center.
Mayall II: A cluster in the Andromeda Galaxy. It is the brightest globular cluster in the Local Group and may have a black hole @ the center. It is seen by some as the the galactic core of a dwarf galaxy that was consumed by Andromada. That's because the stars are very metallic.
NGC 1049: Located in the Fornax Dwarf Galaxy. It is 630,000 light years away. You can see it with a telescope, but you are unlikely to see the galaxy it is in.
Open: A group of hundreds or thousands of baby stars. They aren't bonded to each other, so they spread out. They tend to break up after 50 million years.
Wild Duck: It is one of the most massive open clusters. It is only 316 million years old and it is about as massive 7,500 suns. There is a lot of iron in this cluster. It has a lot of drug dealers (stars that live fast and die young) @ it's center.
Hyades: The closet cluster to the Sun. It is 153 light years away and only 650 million years old. 5 of the brightest stars are becoming giants because they used up the hydrogen @ their core. There was more stars in this cluster in the past.
Butterfly: It is 1,590 light years away and 94 million years old. It is such a baby. It has a lot young and wild blue stars, but it's brightest star is a orange giant star. 120 stars have been discovered in this cluster. It orbiting in our galaxy.
NGC 7419: It has 5 red supergiants, but no blue supergiants. It is only 15 million years old, which makes it a zygote. Is about as massive as 8,500 suns.
Jewel Box: A very young cluster with about 100 stars. It is 6,440 light years away and 16 million years old. There are bright supergiants there; some of the brightest stars in the Milky Way. Crux constellation is where it is located.
Intergalactic Star
A rogue (intergalactic) star is not bound to a galaxy. It originated in a galaxy and out knocked out of it. This could have happened because of a galaxy merger or traveling too close to a supermassive black hole. In the 90's rogue stars was discovered in the Virgo and Fornax galaxy clusters. There are 675 rogue stars @ the edge of our galaxy.
Exotic Stuff
Brown Dwarf: This is an almost star. It didn't become massive enough for it core to have nuclear fusion of ordinary hydrogen. But they are able to fuse an isotope of hydrogen or lithium. Some brown dwarfs have iron rain and older ones have methane in their atmosphere.
Neutron: This is the core of a very massive star after it went supernova. The explosion was so powerful it caused the protons and electrons to fuse together. They are as big as a city and as massive as the Sun. There are 9 types of neutron stars. I will write about some of them.
Hercules X-1: This a neutron star taking material from its companion star, because of this it emits X-rays.
The Magnificent Seven: They are 7 neutron stars that are close to each other and about 300,000 years old.
Aquila X-1: It is a low mass binary star system, that emits a lot of X-rays. The neutron star there is absorbing material from its main sequence companion.
Scorpius X-1: It emits more X-rays than the Sun. This is because it's sucking the blood of its wife.
Pulsars: Neutron stars that emit many different electromagnetic waves from their magnetic poles and they spin a lot. It is like a lighthouse; sometimes the beams are in Earth's direction, sometimes they ain't. You can think of it as a light switch someone is turning on and off very quickly.
Crab Pulsar: Located in the Crab nebula and it is very young. It comes from the supernova that was observed 1054 by a Chinese astronomers. It emits X-rays and gamma rays.
PSR J0540-6919: Located in the Tarantula Nebula in the Large Magellanic Cloud. It was the first pulsar discovered to emit gamma rays outside the of the Milky Way.
Hulse-Taylor binary: A binary star system of a regular neutron star and pulsar. It was the first binary star system with a pulsar discovered.
AR Scorpii: The only known white dwarf pulsar and it has a red dwarf companion. It is 380 light years away. The red dwarf emits radio waves, light, and ultraviolet waves.
Magnetars: Neutron stars that have a magnetic field that is 1,000 trillion times stronger than Earth's!!! If it surfaces cracks it will release an amount of energy greater than the Sun!!!!
SGR 0525-66: First magnetar discovered outside the Milky Way.
SGR 1900+14: It emits X-rays and gamma rays @ random. It formed after a recent supernova and it's 20,000 light years away. In 1998 it emitted so much energy a satellite had to be shut down, so it wouldn't get damage. That burst caused a ring of matter to form around it.
Quasars: They are bright collection of gas that orbits a supermassive black hole. They look like stars, but they aren't. They are the brightest objects in the universe.
J2157-3602: Most powerful quasar discovered next to the fastest growing black hole.
3C 147: Redshifted in a galaxy 6.4 billion light years away. It took 5.1 billion years for the light from that qausar to reach us.
J0313-1806: The most distant quasar discovered; that is next to the oldest known supermassive black holes.
Blazers: They are quasars that our beaming material and/or electromagnetic waves @ light speed in the direction of Earth.
Black Hole: It is the core of super-massive star. It has gravity so strong not even light can escape it. Most galaxies have a supermassive black hole @ their center.
GRO J0422+32: Smallest known black hole. It has a companion that is a main sequence star.
Cygnus X-1: It is a binary star system: black hole and blue supergiant. The blue supergiant is being slowly eaten by its friend.
Conclusion
Stars are amazing!!!!!!!!!!!! They are made out of plasma and come from nebula. Most are main sequence and very massive ones create planetary nebulas. They come in clusters: the very old ones are globular and the the babies are open. Some stars are outside of galaxies because they were knocked loose. There are several exotic stars.
References
https://en.wikipedia.org/
https://www.space.com
https://science.nasa.gov/astrophysics/focus-areas/how-do-stars-form-and-evolve
https://www.britannica.com/science/star-astronomy
https://astronomy.swin.edu.au/cosmos/q/quasar
https://imagine.gsfc.nasa.gov/science/objects/neutron_stars1.html
https://www.nationalgeographic.com/science/article/black-holes
https://www.noao.edu/jacoby/
https://www.universetoday.com/45775/famous-stars/
astronomy.com
https://medium.com/@sin_gularity/9-types-of-neutron-stars-3566cb18c7b8
