Does Light Traveling Through Space Wear Out?

The telescopy, built for astrophotography in a light contaminated San Diego yard, pointed to a galaxy far away from the ground. My wife Cristina, the first spacecraft went like a flowing on my tablet. Glittered on the screen in front of us.

“That’s what Pinwheel Galaxy“I said. Name, because this Pinwheel contains a trillion star.

Light from Pinwheel, Universe, about 150 quintile miles, to reach my telescope.

My husband wondered: “Does not tire light during such a long journey?”

His interest caused a thought-provoking conversation about light. As a result, why does not wear light and lose energy over time?

Let’s talk about light

I am a one astrophysicsAnd one of the first things I learned in my education, how much light in the roads against our intuitions. It is the light electromagnetic radiation: Basically an electric wave and a magnetic wave together together and walks together Space time. Froze There is no mass. This point is critical, because the mass of an object is a speckle of a dust or speech, limits the highest speed that it can pass through space.

However, since the light is unprotected, the maximum speed limit in a vacuum, about 186,000 miles per second (300,000 kilometers) or almost 6 trillion miles a year (9.6 trillion kilometers). Nothing passing through space is faster. To perspective:, at this time, the light particle walks around twice around the earth.

As incredibly fast, the space is incredibly spread. 93 million miles (about 150 million kilometers) from the ground above the sun To reach us for eight minutes. In other words, the sunlight you see is eight minutes old. Alpha CentauriAfter the sun, we are the closest star, 26 trillion miles (about 41 trillion kilometers). So as soon as you see in the night sky, his light is only four years old. Or, as astronomers say, this Four Light Years.

https://www.youtube.com/watch?v=1btxxcr8awq

Review Cristina’s question with great distances in mind: How can light travel throughout the universe and slowly lose energy?

In fact, a little light loses energy. This is when it happens Leaps from somethingFor example, inter-steeper powder and scattered. But the most light goes and goes without a collision with just one thing. This is almost always because The space is mostly empty-Houmlyess. So there is nothing on the road. When the light is not cut, no energy is lost. This can save the second speed per 186,000 miles forever.

It’s about time

Here’s another concept: take a picture like an astronaut At the International Space Station. 17,000 miles per hour (about 27,000 kilometers) orbit. Compared to someone on earth, the goal swatch will sign more slowly than 0.01 seconds.

This is an example increased time-Mim moves different speeds in different conditions. If you actually move quickly or close to a large attraction area, your clock will slower than you, or slower than you are more slowly than a large attraction area. I say the owner, Time is relatives.

Think that this light is now Including time. Picture sits on a photona light particle; Here you live in maximum time dilation. Everyone on earth will take you to the speed of the light, but the time of your reference will be completely stopped.

This “Hours” measurement time is two different locations in a very different speed, the photon moves in the speed of light and is slowly moving rapidly around the sun.

More, when traveling to the speed or near the light, the distance between where and where you go. That is, the earth itself becomes more compact in the direction of movement, so your journey should be shorter if you can go faster. In other words, for the photon, the space is understood.

This returns us to the pinwheel galaxy. From the influence of Photo, a star in the galaxy and then swallowed a pixel in my back yard. Traveling in space, traveling, travel was infinitely fast and endless short, a small part of the second.

However, from our prospects on earth, the photon left the Galaxy 25 million years ago, and walked 25 million light years until my tablet on my tablet.

And there, a surprising image on a cool spring night, inspired a delicious conversation between Nerdy Scientist and his interesting wife.

Jarred RobertsProject scientist, University of California, San Diego. This article is republished Conversation Under the Creative Commons license. Read original article.