Does light travel across space?

My telescope, which was prepared for astronomical photography in the backyard of light, was directed to a galaxy that is not known about the ground. My wife, Christina, walked like the first satellite image broadcast on the tablet. Glow the screen in front of us.

“This is it Pinwheel GalaxyI said: The name is derived from its shape – although this wheel contains about a trillion stars.

Binwheel’s light traveled for 25 million years throughout the universe – 150 Quintillination – to reach my telescope.

My wife asked, “Do you not get tired of light during such a long journey?”

Her curiosity sparked an interesting conversation about light. In the end, why does the light not wear and lose energy over time?

Let’s talk about light

I Astronomical physics worldOne of the first things I learned in my studies is how light behaves in ways that challenge our intuition. Light Electromagnetic radiationBasically, an electric wave and a magnetic wave associated together and traveling through Space. He – she He does not have a block. This point is crucial because the object mass, whether it is a spot of dust or space ship, limits the maximum speed that can go across space.

But since the light without a block, it is able to reach the maximum speed in a vacuum – About 186,000 miles (300,000 km) per second, or Almost 6 trillion miles per year (9.6 trillion kilometers). Nothing travel through space faster. To put it in its correct perspective: while it takes you to flash your eyes, a particle moves from the light around the Earth more than twice.

Unscrewed quickly, the space is spreading incredibly. The light of the sun, 93 million miles (about 150 million km) from Earth, takes only Eight minutes to get to us. In other words, the sunlight you see is eight minutes. Alpha SantoriThe closest star to us after the sun, 26 trillion mile (about 41 trillion kilometers). So by the time you see it in the sky of the night, the light of light is more than four years. Or, as astronomers say, it is so Four light years away.

https://www.youtube.com/watch?

While taking these huge distances into consideration, think about the question of Christina: How can light travel across the universe and not slowly losing energy?

In fact, some light loses energy. This happens when Wears somethingLike dust between stars, which is widespread. But most light goes and goes, without colliding with anything. This is always the case for The space is mostly empty– nothing. So there is nothing on the way. When the light travels without obstacles, it does not lose any energy. It can maintain that the speed is 186,000 mph forever.

It’s time

This is another concept: Imagine yourself as an astronaut On board the International Space Station. You revolve around 17,000 miles (about 27,000 km) per hour. Compared to someone on the face of the earth, your rape watch will mark 0.01 seconds slower over one year.

This is an example on Stretch time– Time is moving in Various speeds under different circumstances. If you are really moving quickly, or near a large attractive field, your watch will slow more than one person moving slower than you, or who is beyond a large attractive field. To say this briefly, Time is relative.

Now think that the light Insecure in an incomparable time. A picture sitting on a PhotonEssential particle of light; Here, you will test the maximum time to extend the time. Every person on the face of the earth will record you at the speed of light, but from your reference stirring, the time will stop completely.

This is because the time of measuring the “hours” in two different places walks two completely different speeds: the photon moves with the speed of light, and the relatively slow Earth’s speed roams in the sun.

What is more, when you travel or near light speed, the distance between your place and where will go shorter. That is, the space itself becomes more tight in the direction of movement – and the faster, the shorter your journey. In other words, for the photon, Space is crushed.

This brings us back to my picture of the wheel. From the photon perspective, a star inside the galaxy removed it, then absorbed it with one camera in the rear courtyard, exactly at the same time. Since the area was crushed, to the photon, the journey was fast without borders and short -without borders, which is a small part of a second.

But from our point of view on Earth, the photon left the galaxy 25 million years ago and traveled 25 million light years in space until it landed on the tablet in the backyard.

There, on the cold spring night, her amazing image inspired a delightful conversation between Nerdy and his strange wife.

Jared RobertsProject world, University of California, San Diego. This article has been republished from Conversation Under the creative public license. Read The original article.