The other day, I was having a chat with my cousin and as usual our talks inevitably wandered off to the topic of the universe and the recent discoveries in this space.

Then something he said really sent me into a deep thinking frenzy. He pointed out that telescopes are like time machines. For example, if an alien race 65 million miles away pointed their telescopes towards the Earth right now, they could witness the wiping off of the dinosaurs.

Isn’t that an eye-opening realisation? I mean I always knew this for a fact that since light has a constant speed and the universe is so unthinkably large, that even it takes millions of years to travel long distances.

But the realisation that this essentially makes ours and anyone else’s telescopes in the universe, sort of like time machines, is thrilling, to say the least. At least for me.

A Little Explanation

If you are reading this, there is a great chance that you are already familiar with what I’m talking about. But if you are not, let me quickly explain it to you in simple terms.

I am sure that in school you must have learned that light takes 8 minutes and 20 seconds to reach our planet. You can calculate this yourself if you know the speed of light and distance between the Earth and the Sun.

So, the light that we see coming from the sun at any given point, actually left the sun a little more than 8 minutes ago. That really means that we are witnessing the past of the sun by 8 minutes or so.

And that is just between the Earth and the sun. The further away any object is from us, the further we are looking into its past. That’s just the way our universe works, folks!

Telescopes - The Time Machines

When it comes to the sun, we can use our eyes, but when it comes to distant stars and galaxies that are not visible to the naked eye, we use powerful telescopes like the Hubble Telescope.

These telescopes are useful in the understanding of the universe not just because they let us see what’s out there but also the past of it all. That’s why we have been able to study how different objects in the universe develop over time.

I just wonder what wonders we could witness if had a telescope thousands of times more powerful than Hubble. Of course it is not really time travel and we can’t change anything, but at least we can witness the actual past of something in the universe.

That to me, is such a huge thing and something that not many people think about while thinking of telescopes. This surely makes me want to go out and buy one of my own!