What does it mean to say that the Milky Way is 100 000 light years wide?

Question

What does it mean to say that the Milky Way is 100 000 light years wide?

Answer 1

it takes light 100,000 years to go from one end of the galaxy to the other

Answer 2

Some people find the term "light year" confusing. It's not actually a measurement of time, it's a measurement of distance. The speed of light is always the same -- 186,000 miles per second. In a year, light travels almost 6 trillion miles. That's one light year. Light years are what astronomers commonly use to measure distances beyond our solar system because the universe is so huge. Our galaxy, the Milky Way, is thought to be about 80,000 to 100,000 light years in diameter, so that would be up to 600 quadrillion miles (approx) across. The nearest large galaxy to the Milky Way is Andromeda, which is 2.5 million light years away.

Answer 3

It means that the Milky Way galaxy is 600,000,000,000,000,000 miles wide. That is because a light year is a measure of distance, not time, despite the word "year" in the name. A light year is about 6 trillion miles, so 100,000 light years is 600 quadrillion miles.

Another way of looking at it is the "drive time" to cross the Milky Way is 100,000 years if you drive at the speed of light.

Answer 4

A light year is the distance light can travel in one year. Light travels at approximately 186,000 miles per second, in a vacuum.

So, when you say the Milky Way galaxy is 100,000 light years wide, it means that light takes 100,000 years to travel from one side of the Milky Way galaxy, to the other side of the Milky Way galaxy.

Answer 5

A light year is defined as the distance an unobstructed light beam would travel in a year, which is 5,879,000,000,000 miles >*5 trillion,879 billion miles<. Multiply that sum by 100,000 years and that gives you the perspective of how vast this world is. Considering that the milky way is only a small galaxy in a universe of thousands of galaxies, it makes the statement is Psalms 8:3 & 4 take on real meaning:

  ¶When I consider thy heavens, the work of thy fingers, the moon and the stars, which thou hast ordained;
4  What is man, that thou art mindful of him? and the son of man, that thou visitest him?

Answer 6

It takes light 100 000 years to go across it. Use the speed of light and convert it to an actual distance if you need to.

Answer 7

A light-year is a unit of measure. It measures the distance that the light travels in one year at its maximum speed (speed in vacuum) of 299,792,458 meters per second (1,079,252,848.8 km/h).

Our galaxy (Milky Way) measures about 100,000 light-years in diameter. This means that a ray of light would take 100,000 years to travle from one side to the other of the spiral disk of our galaxy.

It measures also about 10,000 light-years at the center (the bulge) in thickness.

Note: contrary to most people believe, you WILL NOT take 100,000 years to travel from one side to the other at the speed of light. You take way less.

Based on Relativity, for us, hereon Earth, at our constant speed, light takes 100,000 years, but for a ship traveling at that speed, for those onboard, would take a mere 100 years only. For us here on Earth, it wil be 100,000 years, but for the ship, it will be just 100 years.

This is true not just for traveling in the galaxy, but fro traveling anywhere at any speed. The faster you go, the faster the clock outside your ship will tick, or the slower the clock in the ship will tick as seen by those outside the ship that are not moving that fast.

Time is relative to the speed.

Of course, nothing can reach the speed of light, again, based on Relativity, but you could reach speeds that are close to it, and be able to travel around our galaxy in just years. But on Earth, years will flay by, and you will have jumped into the future when you come back. It is the price for traveling at that speed.

Answer 8

Light takes 100,000 years to travel across the width of the galaxy.

Answer 9

It would take a beam of light 100,000 years to travel the distance from one end to the other.

Answer 10

That if you could travel the speed of light. It would still take you 100,000 years to get from one end of the galaxy to the other.
Light travles at: 186,000 miles per second

Its freaking huge.