What is the difference between regular years and light years?

Question

I am starting to get interested in Astronomy and I don't understand what all these new terms mean, mainly the difference b/w the regular years and light years. How many miles is a light year?

Answer 1

A light year is the measure of distance, not time. It's how far a ray of light can travel in a year, 5.something trillion miles. I wonder how they measure that.

A "regular" year measures time, not distance. If you mean a year on Earth it is 365 days -- how long it takes for the planet to go around its star (the sun) one time. For instance, a year on Mercury is shorter: 87.9 Earth days = one Mercury year.

Answer 2

A light Year is the distance that light travels in one Earth Year.

It may be calculated by multiplying...

186,000 Miles/Sec x 60 Sec/Min x 60 Min/hour x 24 Hr/Day x 365 Days/Year = 1 Light Year

or roughly 6 Trillion Miles.

Answer 3

The duration of a regular year and a light year is identical. However a light year is used to measure the distance to far away astronomical objects. For example the nearest star to earth is about four light years away and photons emitted from the star take about four years to reach us (at the speed of light). If the star exploded today it would take four years before we could see the explosion. In a way, knowing how far away an object is in light years lets us know both the distance to the object and how 'old' the light we are observing must be. Many distances are actually best estimates. Even sunlight takes 8 minutes to reach us and we always see how the sun appeared eight minutes ago including its past position although the earth has rotated in the meantime. At sunset we still see the sun even though it is now actually below the horizon.

Answer 4

A light Year is a measure of Distance, similar to a Kilometer, while a "regular year" is a measurement of time.
Specifically, a light year is the distance which light travel in the time of a year.
This unit is used in Astronomy since normal land based units of distance are hopelessly small when compared to distances in space.
I light Year is about 6,000,000,000,000 Miles! (6 Trillion )
It would be very cumbersome to use miles to express the distance to even near neighbours in space. Andromeda, our galactic neighbour is 2.8 million light years away. Try writng that in Miles a few times and you will see what i mean.

Adolph

Answer 5

A light year is a measure of distance, rather than time. We used to spell it with a hypen, as in light-year, which made it a little easier for people to understand.

It means the distance light travels in a year at 186,000 miles per second. (About 5,800,000,000,000 miles)

So a light-second is 186,000 miles and a light-minute is 11,160,000 miles, and so on. We say it that way because it is a compound measure like man-hours or foot-pounds.

Answer 6

Nothing is different. All that the term light year is saying is the distance light travels in one year. Same amount of time just the distance. And that distance is about 5.8 Trillion miles a year.

Answer 7

A "regular" year is a unit of time; a light year is a unit of distance -- about 6 trillion miles.

Answer 8

A year is defined as the time taken for a planet, any planet, to make one complete orbit of the Sun. For Earth that is about 365.25 days. For Mercury it is about 88 Earth days.

A light year is defined as the distance travelled by light in one Earth year. Light travels at 300,000km per second, so one light year is 300,000 x 60 x 60 x24 x 365.25 which is roughly 9,500,000,000,000km (about 5,900,000,000,000miles).

Answer 9

A year is ~365.25 days. It is the amount of time it takes the Earth to make one orbit around the sun. A light year is the distance light travels in one Earth year:

186,000 mi/sec x 60 sec/min x 60 min/hr x 24 hr/day x 365 days/yr

It works out to about 5.8 trillion miles.

Just to clarify, a year is a measure of time. A light year is a measure of distance.

Answer 10

like everyone is saying, its not a big of deal as the tv makes it seem. You probably are thinking "then why are such drastic measures being taken?" The reason why its such a big deal its because its a new flu thats infecting people. It has infected humans before, but not like it is now. It is just like the flu, except we have no immunity to it, or so they know so far. They are still researching wheter any human has had immunity to it yet. That is the reason why so many schools are being closed and so on, because we arent immune to swine. But that doesnt mean its going to kill you, there is treatment ofcourse.