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Light moves pretty fast. It actually moves the FASTEST out of anything that we know of (for now). Light moves at about 300,000 kilometers per second. When I’m in a rush on the freeway, I drive up to 145 kilometers per hour (90 miles per hour) which is only 0.04 kilometers a second. The fastest plane moves at about 12,000 kilometers per hour which is about 3.3 kilometers per second. Light moves a lot faster than that plane and my car.
We also know that things in space are really far away from us. Take our sun for example, it’s about 150 million kilometers away from Earth. The sun emits a light, but even moving at the speed of light, the light takes about 8 minutes to get to us. (You do this calculation by taking 150 million, the distance, and dividing it by 300,000, the speed of light, and that will give you the time it takes in seconds, so to convert to minutes you divide by 60 and that will give you about 8 minutes) So technically, if you look up at the sun (do not recommend without sunglasses) you aren’t seeing how the sun looks right now. You’re seeing how it looked 8 minutes ago. So you’re looking 8 minutes in the past. Let’s take this up another level because 8 minutes is alright. But what if we could look years back in time. Let’s take a look at the star closest to Earth, Proxima Centauri. Even though it’s the closest, it’s still 40,208,000,000,000 kilometers away (40 trillion). So even moving at the speed of light, which we said earlier was way faster than anything we got here on Earth. It takes about 4.25 YEARS for the light on Proxima Centauri to reach us. So if I find Proxima Centauri and I look at it, it doesn’t even look like that anymore. That’s how it looked 4.25 years ago, I’m looking 4.25 years in the past!!
Andres' Astronomy Adventures 
One response to “Speed of light in Space”
These are some very fascinating points that you brought up Andres. As a human, we like to compare relative speeds to things which we are comfortable with. It is crazy that even the fastest plane ever created only moves at a mere fraction of the speed that light moves at. Do you think humans will ever be able to develop an aircraft that travels close to the speed of light? How long do you think it would take? I also analyzed the size of cosmic objects in my blog1 post. However, I looked at the size in term of distance. If you want to learn more about the size of the Milky Way, feel free to check out my post!
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