Earth logo

The Incredible Speed of Light

It is believed that no other thing can reach the speed of light. Therefore, you could say that it's the maximum speed limit throughout the whole universe.

By Unravelling the UniversePublished 5 months ago 3 min read
The Incredible Speed of Light
Photo by CHUTTERSNAP on Unsplash

In a vacuum, light travels at almost 300,000 kilometres or 186,000 miles per second.

Light travelling through the Earth's atmosphere would be slowed down very slightly.

The speed of light is so important in many areas of physics.

So what is the speed of light?

It works out at roughly 18 million kilometres, or over 11 million miles per minute, which works out at 1,080 million kilometres, or 671 million miles per hour. Yes, that speed is a bit mind-boggling, to say the least.

Anything that has mass could never reach the speed of light; the vast amount of energy needed would be impossible to achieve.

Could it be possible that in the future we will be able to reach distant areas in space while travelling near the speed of light? I think we can rule that scenario out. The most that we can hope for is to visit objects in our solar system, which, of course, is just our backyard.

The Parker Solar Probe was launched into space in 2018. Its mission is to study the sun and its outer corona. In 2025, it will make its closest approach to the Sun and is expected to achieve a speed of roughly 690,000 kilometres, or 428,000 miles per hour. But even at that speed, we are never going to get very far from our local area in space.

By Federico Respini on Unsplash

The next few lines will hopefully put the speed of light into perspective.

Light speed is 1,565 times faster than the maximum speed the Parker Solar Probe will be able to achieve.

Our natural satellite, the Moon, lies 384,400 kilometres, or 238,855 miles, from the Earth; light leaving the Moon takes just over one second to reach the surface of the Earth.

The circumference of our planet is about 40,000 kilometres or 25,000 miles. If it were possible for light to zip around the Earth's surface, it would do so 7.5 times each second.

The distance from the Earth to our local star, the Sun, is almost 150 million kilometres, or 93 million miles; that short journey for light takes 8.3 minutes.

Proxima Centauri is a small, low-mass star located roughly 40 billion kilometres, or 24 billion miles away from our planet.

Proxima Centauri, Credit: ESA/Hubble & NASA

Not including the Sun, Proxima Centauri our nearest star neighbour, but light would still take over 4 years to travel the distance between the Sun and Proxima Centauri.

It may seem like Proxima Centauri is very distant, but in reality, it is just a step away when considering the size of our galaxy, the Milky Way.

Light would take over 100,000 years to travel across the diameter of the Milky Way.

But our galaxy is minuscule compared to that gargantuan area we call the universe.

With highly advanced telescopes, we can now see objects that are over 13 billion light-years away. It is very hard for us to comprehend these vast distances.

Imagine this, for every year of those 13 billion years, the light from those extremely distant objects will have travelled 9.46 trillion kilometres, or 5.87 trillion miles, towards us.

I could write down the number of kilometres or miles light has travelled in 13 billion years, but it would be meaningless to most of us. Yes, they are mind-boggling astronomical distances.

The end.


We can only imagine what our early ancestors were thinking as they gazed up at the night sky—were they curious about what the heavens had to hide?

Now it is very different, as we have developed sophisticated telescopes and other specialised scientific instruments that are helping to reveal some of the secrets the universe holds.

The evolutionary path of life has been extremely long, but at last, we have arrived. Our highly developed brain has given us intelligence and curiosity; now we can try and make sense of our existence.


You may find my easy-to-understand stories about the universe and life interesting and educational.

If you subscribe to me for free, you will see my latest stories. Regards.

Free to read

Scienceshort storyNatureHumanity

About the Creator

Unravelling the Universe

We can only imagine what our early ancestors thought as they gazed up at the night sky—were they curious about what the heavens had to hide? 

Reader insights

Be the first to share your insights about this piece.

How does it work?

Add your insights


There are no comments for this story

Be the first to respond and start the conversation.

Sign in to comment

    Find us on social media

    Miscellaneous links

    • Explore
    • Contact
    • Privacy Policy
    • Terms of Use
    • Support

    © 2024 Creatd, Inc. All Rights Reserved.