A light year is a way of measuring distance. That doesn’t make much sense because “light year” contains the word “year,” which is normally a unit of time. Even so, light years measure distance.
You are used to measuring distances in either inches/feet/miles or centimeters/meters/kilometers, depending on where you live. You know how long a foot or a meter is — you are comfortable with these units because you use them every day. Same thing with miles and kilometers — these are nice, human increments of distance.
When astronomers use their telescopes to look at stars, things are different. The distances are gigantic. For example, the closest star to Earth (besides our sun) is something like 24,000,000,000,000 miles (38,000,000,000,000 kilometers) away. That’s the closest star. There are stars that are billions of times farther away than that. When you start talking about those kinds of distances, a mile or kilometer just isn’t a practical unit to use because the numbers get too big. No one wants to write or talk about numbers that have 20 digits in them!
So to measure really long distances, people use a unit called a light year. Light travels at 186,000 miles per second (300,000 kilometers per second). Therefore, a light second is 186,000 miles (300,000 kilometers). A light year is the distance that light can travel in a year, or:
186,000 miles/second * 60 seconds/minute * 60 minutes/hour * 24 hours/day * 365 days/year = 5,865,696,000,000 miles/year
A light year is 5,865,696,000,000 miles (9,460,800,000,000 kilometers). That’s a long way!
Using a light year as a distance measurement has another advantage — it helps you determine age. Let’s say that a star is 1 million light years away. The light from that star has traveled at the speed of light to reach us. Therefore, it has taken the star’s light 1 million years to get here, and the light we are seeing was created 1 million years ago. So the star we are seeing is really how the star looked a million years ago, not how it looks today. In the same way, our sun is 8 or so light minutes away. If the sun were to suddenly explode right now, we wouldn’t know about it for eight minutes because that is how long it would take for the light of the explosion to get here.
Q:How Long Would It Take U To Walk In A Light year ?
That would take us some 225 million years (that’s assuming that you managed a constant speed of 20 minutes for every mile and didn’t stop for any bathroom breaks…it would be a little trying, to say the least, especially when one considers that modern humans have only been around for about 200,000 years.
Q:How Long Would It Take For A Spaceship To Travel A One Light Year ?
How long would it take the space shuttle to go one light-year? The shuttle orbits the Earth at about 5 miles per second (18,000 mph). Light travels at 186,000 miles per second, which is about 37,200 times faster than the shuttle. So the shuttle would need about 37,200 years to go one light-year.
Q:If We Travel To Sun Through The Speed Of Light Year How much Time It Would Take To Reach The Sun?
A:The Sun is at an average distance of about 93,000,000 miles (150 million kilometers) away from Earth. It is so far away that light from the Sun, traveling at a speed of 186,000 miles (300,000 kilometers) per second, takes about 8 minutes to reach there.
Q:How Many Light years Away The Moon From The Earth ?
A:The distance from the earth to the moon is 1.25 light seconds, which is roughly 238,900 miles.
Q:How U Can Make out Someone About Light Years. ?
A:Astronomers use the speed of light to measure how far away things are in space. A light-year (ly) is the distance that light can travel in one year. In one year, light travels about 5,880,000,000,000 miles or 9,460,000,000,000 kilometers. So, this distance is called 1 light-year.
Q:How Long Does It Take To Travel 40 Light Years ?
A:Or about 1/17,000 the speed of light. Therefore to go 1 light year at the speed Voyager 1 is going, would take 17,000 years. To go 40 light years, would take 700,000 years.
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