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November,6th,2006 This entire site is done by:NurulHusna Bte Md.Saleh ( 05B0722 ) B.Ed General Science.
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WANT TO KNOW MORE info ABOUT THE STAR THAN BEING EXPLAIN here.. JUST CLICK THE BUTTONS BELOW:
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 To play song
Twinkle twinkle little Star . . .How I wonder what you are...  Up above the sky so high, like a diamond in the sky . . . Twinkle twinkle little star . . .How I wonder what you are . . . -By Mozart –  
 
Glancing up above, it is as if the night sky has been sprinkled with glitters. The view is absolutely amazing..
 The stars looked so small and not so far away.. it feels like as if when you reached out your hand, you could grasps them.
Wondering and appreciating those stars.. a child would have asked, “ What are those twinkling little diamonds doing up there?”
Well, I’m happy that you are here. In this site, I’m trying to help you to understand more about the Stars.
These are the main contents about the stars that I would like to share with you all:
1) The life cycle of a Star 2) The Basic Types of Star 3) Special Stars 4) Curious Questions
Now lets begin by knowing the life cycle of a star.
Do you know that star also have its own life-cycle? As a matter of fact, star has three stages in life.
Star is born from the gathering of gas and dust. These gas are mainly hydrogen, helium and other substances that when mixed together can create energy. (Scientifically the process occurring is called as nuclear fusion processes in the core, but you don’t have to worry about that for now).
Second stage: The star grows up As time goes, they grow into a giant furnace and spent their adult life giving out heat and light. Adult stars have different sizes and colours.
Third stage: The death of the star After living for many billions years, the star eventually dies. Their death can either be peaceful or explosive.
>> This is just a general explanation about the star’s life cycle, so if you are interested to know more, just click on the button at the top, left side.
After understanding the life of the star, let me introduce to you the different kind of stars that are usually found.
Here we have listed seven of the most common type of stars. They are actually more detailed than the ones that have been listed here.
1) Black dwarf This type of star does not shine, causing them to look black. The star have aged after living for million of years and have used up all of their energy to shine.
2) Brown dwarf Nearly the same like black dwarf, but this kind of star gives out a little shine. Usually, this kind of star appears when a star dies.
3) Red dwarf This is the most common star in the universe. The star is small and very cool than the rest of other stars. They can live for many billions and trillions of years.
4) Yellow dwarf This star fairly shines. Our “Sun” is an example of a yellow dwarf. It is a medium-sized star that can live for about ten billion years.
5) White dwarf This star is actually the remaining of a dead star. They are hotter than the other dwarf stars. Thus, our sun will become a white dwarf when it dies billions of years from now.
6) Red giants This star is very large and cool. This star is created before the dead yellow dwarf becomes a white dwarf. So, when our sun dies, it will first become a red giant star and finally turn into a white dwarf star.
7) Red super giants Red super giant star is many times bigger than our Sun. It is the biggest star in the universe. They are created when a big-sized star begin to die. When the red giant star die, it causes a huge dramatic explosion. Then it turns into a neutron star or a black hole.
Now, we are moving to a few more types of stars which are classified as special. However, this does not mean that the other stars are not unique. All stars in the universe are actually very special. Some, however are truly amazing which makes us think that they are special than the others. These stars caught our eyes by their brightness or size.
Here are a few lists of those stars:
1) Binary stars.
2) Black holes.
3) Neutron stars and pulsars
4) Supernovas.
>> if you are interested to know more, just click on the button at the top, left side.
I have gotten these questions from a website, the answers given are also good. I’ve selected few that I think are interesting and worth knowing.
1) Is it possible to count the stars? Well, yes and no. If a very patient person went out night after night, she could count up all the stars she could see. But if she then looked through a telescope and tried to count again, she would find many more stars, because the telescope would help her see faint stars that she couldn't see with her naked eye. If she got an even bigger telescope, she would see even more stars! It is possible for astronomers to guess how many stars there are, though. First, we can use physics to make a good guess about how many stars there are in our galaxy (about 100 billion). Then we can make a guess about how many galaxies there are in the visible universe (also about 100 billion). Then we just multiply these numbers together to estimate the number of stars in the visible universe - ten thousand billion billion stars! 2) How do the stars get names? I mean did the same people name them. Also how many stars are there? A lot I know but do you have the answer? Most of the brightest stars are named after characters in the mythology from various cultures. Many of them (like the planets) therefore have different names depending on where you are in the world. They were often named in pre-history by our ancestors who gazed at the stars trying to find patterns and stories in what they saw (this is also where the names for the visible planets and the constellations came from). Modern astronomers have given the stars new names so that they can keep track of them more easily. Stars are named for the constellation that they lie in with the brightest star in a constellation being alpha and so on throught the greek alphabet. For example, Betelguese which is the brightest star in the constellation Orion, is also called Alpha Orionis. There is a nice website on the names of stars at The constellations and their stars and another at Star Names.
Stars that are discovered today are in general named for where they are
in the sky or the person who found them, which gives them really ugly
names like: Once they run out of Greek letters in a constellation, astronomers also use numbers (eg. 51 Pegasi - a famous star because of the planets around it). Variable stars are called things like RR Lyrae (in Lyre) or TT Arietis, in order of discovery (ie. AA is the first variable star in a constellation, then AB. When they reach ZZ they start with number 677!?) There are probably other ways that stars are names. Each star usually has more than one name which astronomers have to keep track of in the information that they keep on it. Apparently about 2-300 stars were named in the past (between 500 to over 2000 years ago), these are the ones with (in general) mythological names. With the naked eye you can see about 4000 stars in each hemisphere of the sky. There are probably several million in the most up-to-date astronomical catalogues. There are at least a billion stars in the Milky Way (our galaxy), probably quite a few billion. There may be an infinite number of stars in the whole universe, we just don't know yet! There are at least 100 billion billion in the observable universe (this is saying that there are about 100 billion galaxies each with a billion stars, which is most likely an underestimate). This is more than any human can deal with, so the exact number doesn't matter too much. Let's just say that there are a lot of stars! 3) Why do stars twinkle? The songline goes "Twinkle twinkle little star". What is the cause of the "twinkling" of stars? Does light from planets "twinkle" as does light from stars? A young person of my acquaintance asked me this question, and I didn't have a good answer. Stars twinkle because of turbulence in the atmosphere of the Earth. As the atmosphere churns, the light from the star is refracted in different directions. This causes the star's image to change slightly in brightness and position, hence "twinkle." This is one of the reasons the Hubble telescope is so successful: in space, there is no atmosphere to make the stars twinkle, allowing a much better image to be obtained. Planets do not twinkle the way stars do. In fact, this is a good way of figuring out if a particular object you see in the sky is a planet or a star. The reason is that stars are so far away that they are essentially points of light on the sky, while planets actually have finite size. The size of a planet on the sky in a sense "averages out" the turbulent effects of the atmosphere, presenting a relatively stable image to the eye. 4) What is the difference between a "star" and a "sun"?Are all of the points of light in the night sky, other than the moon, planets, and artificial satellites, that we call stars also suns? A star is called a "sun" if it is the center of a planetary system. A large number of planets have been found that orbit other stars, thus making these stars officially "suns." Chances are that a large percentage of the stars in the galaxy also have planets orbiting them, which would make them suns as well. The number of extrasolar planets that have been detected is increasing very rapidly, as we find new planetary systems. So a large number of the stars that you see are also suns. However, many objects in the night sky are not stars. You mentioned man-made satellites, planets and the moon. From earth, there are many other objects that we see as points of light, such as far-away galaxies, so not every point of light is a star!
Well, that’s all for now.
Hopefully you enjoy your visit here. You are welcome to come and visit again. Thank you.
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