How Many Stars Are There In Space?

Scientists Estimate The Number Of Stars In Space.

Scientists like me have figured out how to estimate the total number of stars in the universe, which includes everything that exists.

Throughout the universe, there are groups of stars, planets, gas, and dust called galaxies.

Just like people, galaxies come in different sizes and shapes.

Our planet is in the Milky Way, a spiral galaxy with stars forming spiral arms around its centre.

Other galaxies are oval-shaped (elliptical), and some are irregular with various shapes.

Estimating the amount of galaxies

Astronomers begin by figuring out how many galaxies are in the universe.

They do this by taking really close-up pictures of tiny pieces of the sky and counting all the galaxies in those pictures.

Then, they multiply that number by how many pictures it takes to capture the entire sky.



The result: There are about 2,000,000,000,000 galaxies in the universe, which is 2 trillion.

Estimating the amount of stars in those galaxies.

Astronomers aren't sure exactly how many stars exist in each of those 2 trillion galaxies. Most are extremely far away, making it hard to know for sure.

However, we can make a good estimate of the number of stars in our own Milky Way galaxy. These stars are quite different from one another, coming in various sizes and colours.

Our Sun is a medium-sized, medium-weight, and medium-hot star. It's around 27 million degrees Fahrenheit (15 million degrees Celsius) at its centre.



Bigger, heavier, and hotter stars usually appear blue, like Vega in the Lyra constellation. Smaller, lighter, and dimmer stars often have a reddish colour, like Proxima Centauri, which is the closest star to us except for the Sun.

A Huge Number!

Stars that are red, white, or blue shine with varying amounts of light. Astronomers can guess the total stars in our galaxy by checking this starlight – particularly its colour and brightness.

Using this method, they found out that our Milky Way has around 100 billion stars – that's 100,000,000,000.

Now, let's move forward. Taking the Milky Way as a guide, we can multiply the typical number of stars in a galaxy (100 billion) by the total galaxies in the universe (2 trillion).

The result is a truly amazing number. There are approximately 200 billion trillion stars in the universe. In other words, it's 200 sextillion.

That's 200,000,000,000,000,000,000,000!

The number is incredibly huge, and it's tough to imagine. But here's a way to think about it: It's about 10 times the number of cups of water in all the Earth's oceans combined.

Next time you look at the night sky, consider this – and then ponder what might be going on in the trillions of worlds circling those stars.