How many years is a light-year when it moves?

At the speed of light 1.5 million years

None. Even though the two terms sound as if they're two forms of the same thing, they're not. A "year" is a period of time. It's the time between two of the same person's birthdays, the time between...

A light year is how far light travels in a year. So one year if you go the speed of light....

"Light year" is a distance ... it's the distance light travels in one year, or about 5,878,700,000,000 miles. "Year" is a period of time ... it's the time elapsed while the earth makes one complete...

Zero. Light years are a measure of distance, not time.