Discover The Incredible Life Cycle Of A Star

 In Space

Why do we wish upon stars? According to experts, this idea dates back to 127 AD. In ancient Greece, an astronomer by the name of Ptolemy noted that the Gods occasionally gaze down between the glistening spheres out of mild curiosity. So, when the Greeks wished on a star, they believed the Gods were listening and perhaps would make their wishes come true. This is when the incredible life cycle of a star began.

Of course, when you wish on a star, there’s a good chance that the star is already dead. The light reaching your eyes years later is all that is left of that big ball of gas.

So, what is the life cycle of a star?

Well, as a Waterhog once suggested to a meerkat, a star is a big ball of hydrogen and helium gas. They can be massive or tiny and differ greatly in power and temperature levels. They live for billions of years, passing through a few stages before they finally blink out.

Our own sun is just one giant star, and yes one day, it will die. To help you shake that rather depressing thought, let’s look at the life cycle of a star that fill our galaxy, our universe and all of space.

Lifecycle of a star

Congratulations, It’s A Bouncing Baby Ball Of Gas

Thinking about stars as babies isn’t actually that ridiculous when you consider that they form in nurseries that are also known as nebulae. In Latin, this means cloud, and that’s exactly what they are. A big cloud of gas and dust which will give rats a run for their money. Rats produce around forty babies a year. Nebulae can ‘give birth’ to thousands of stars.

How does a star become a star? A great talent agent! Bad jokes aside the dust and gas gather together in clumps. When a clump is big enough, it rises and builds up mass, up until the point it just collapses in on itself. This occurs due to gravity. The sheer force of the clumps gravity triggers the collapse. When this happens, the temperature rises due to the cloud becoming condensed which causes nuclear fusion. At that point, a star becomes a protostar.

Those Terrible Teen Years

The next stage for the star is to become part of the main sequence. This occurs once it has built up enough mass. It basically eats up the dust and gas in the clouds around it to become what we know as the main sequence star.

When this happens, the star brings hydrogen molecules together, fusing them to produce helium. This is what we mean by nuclear fusion, and it really could be seen as the teenage life of a star because it’s when its still growing. However, unlike us, stars can stay a teen for billions of years.

Did you know our sun was just a moody teenager? It’s true which is why we don’t have to worry just yet about the lights going out.

Have you ever wondered why some stars shine brighter than others? Well, this is all to do with how much mass they accumulate. If a star has more mass, it shines brighter. Now we move onto the next stage answering the age-old question. Is Bigger really better?

The Biggest Loser?

Just like in humans, more mass tends to mean a shorter lifespan for the star. In other words the bigger they are, the harder they fall.

When we left off our teen star had stopped going crazy spinning it’s gas around. Its temperature had stabilized after reaching it’s hottest point, and it had reached the happy resting point as the main sequence star. With the life cycle of a star, what could happen next?

Remember, during this time the star is busy turning hydrogen into helium. But what happens when it runs out of stock. Now the star no longer has a heat source, and that means it becomes unstable. The hydrogen shell of the star expands, and then it begins to glow red.

It becomes a big beautiful, slightly temperamental Red Giant! You can always tell the temperature of a star by its color. Cool stars go red or orange while hotter stars are often white or blue.

Since a star stays a teen for billions of years, it doesn’t hit middle age. Instead, we’ll skip right on ahead to the twilight years. Up until they become a red giant the stars continue along the same path. But after that, things will change dramatically depending on how much mass a star has.

The first is the path to become a Black Dwarf.

A Peaceful Death

A star becomes a black dwarf if it has a low level of mass. Do you want the good news? Our sun is a low mass star. That means it’s not going to go boom but before you get too excited when it does die so will life on planet earth. During that time when the outer area of the star expands inside helium becomes caron. At this point, a low mass star collapses again inside the core. The out layer is pushed out and becomes a new nebula, thus completing the cycle of – for lack of a better word – life.

That core then cools down retaining its luminosity as a white dwarf. Eventually, it loses all energy and becomes a black dwarf.

Life cycle of a star

The other option is far more interesting.

A Violent End

For the second outcome to occur, a star needs more than five times the mass of our own sun. If a star does have this level of mass, it still becomes a Red Giant. Carbon atoms are still formed, but as the temperature rises, other atoms are formed as well including oxygen, nitrogen, and iron. Eventually, the core will contain nothing but iron, and then the process of fusion finally stops. Due to the huge mass of the iron core it collapses. The matter then starts to bounce off the surface and thus a massive explosion occurs. You’ll know this as a supernova.

It’s an incredible event that triggers a luminosity with the power of an entire galaxy filled with stars. The star ends its life with a brilliant bright burst of light, and then it’s gone. Though sometimes, protons and neutrons will be created that become new dense stars.

We hope you have found this information interesting and that you now understand the full life cycle of a star that you may wish upon in a dark night sky.

We have more articles about Space! Check out our article on black holes if you want a really interesting read.

Matt Cameron

About Matt Cameron

Hard-working, dedicated, and passionate are three traits that describe me. I've spent my entire life learning the skills that I need to be able to be a successful entrepreneur. Whether I'm doing work for my companies, or writing content for my blogs, I'm always giving it my best effort.

View All Posts
Recommended Posts

Leave a Reply

Be the First to Comment!

Notify of

Start typing and press Enter to search

Fermi Paradox