how was the light year discovered?

Answer 1

A light year is a measure of distance, so it wasn't "discovered". It is more like "invented".

A light year is the distance something going at the speed of light (186,000 miles per second) would go in a year.

So you figure out how many seconds are in a year
(60X60x24x365.25 = 31,557,600)

multiply that my how many miles light travels in a second
(186,000 more or less)

and you get

5,869,713,600,000 miles.

That is what a light year is.

It is a measure of DISTANCE not of time.

Astronomers started using it when they started figuring out how far away the stars really are. They needed a meaurment that was easy to deal with. Considering that the closest star is about 4 l/y away and some are thousands of light years away, miles and kilometers wasn't going to cut it... everything would be at least 18 TRILLION miles away. If all the numbers you are dealing with are that big it gets really hard to do the math.

They used Parsecs for a while, ( a parsec is about 3.26 light years if I remember right). The parsec was developed from the mathematical/geometric method used to determine how far away stars are (it is the PARalax of of one arc SECond....PARSEC. get it?). But with advances in astronomy different methods of determining how far away stars are began to be used so light years wound up replacing Parsec for most uses.

Answer 2

In the past decade, scientists have found more than 160 extra-solar planets -- planets circling stars outside our solar system. Most of the discoveries were made indirectly, by measuring the "wobble" in a star's motion caused by the gravitational pull of its planet.

To make a star wobble, the planet has to be very large -- many are several times the size of Jupiter -- or very close to the star, as Mercury is to the sun. None of the planets discovered by this method are believed capable of sustaining life.

The current discovery, reported in today's issue of the journal Nature in a paper signed by 73 researchers, took advantage of a relatively new technique called gravitational microlensing, based on Einstein's precept that light from a distant star is bent by the gravitational pull of intervening stars, or other large bodies, on its way toward Earth.

The "lensing incident" distorts the incoming starlight, causing it to brighten for about a month. If the intervening star has an orbiting planet -- even a small one -- it will cause a supplemental "blip" in brightness. To analyze these planets, astronomers must observe the microlensing event continuously for as long as it lasts.

On July 11, the Optical Gravitational Lensing Experiment search team, which surveys millions of stars, detected a microlensing event in the constellation Sagittarius, prompting two telescope networks -- the Probing Lensing Anomalies Network, or Planet, and RoboNet -- to begin observations.

On Aug. 10, astronomers at La Silla Observatory in Chile saw what they had been looking for: "This small brightening was . . . our blip in the night," said Nature lead author Jean-Philippe Beaulieu of Planet and the Institut d'Astrophysique in Paris.

Bennett, another Planet researcher, added that there will be more small planets to come. Microlensing has so far detected three exoplanets -- two giants and OGLE-2005-BLG-390Lb -- and "higher-mass planets are more easy to discover," he said. So if scientists have already found a small one, "these must be substantially more common."

Answer 3

I don't think at anybody "discovered" the light-year.

Light-year is a unit of distance. It's like asking how the mile was discovered.

Answer 4

I don't think discovered would be the right description. Created would be better. When you're talking about the vastness of space, miles or kilometers aren't really a good way to measure distance (you'd get numbers like 100000000000000000000000000000000 or even bigger), so astronomers created the light year to measure distance. By the way, just one light year is equal to 5,880,000,000,000 miles

Answer 5

It wasn't discovered. It was just established as a standard measurement of distance like the meter or the mile.

Answer 6

As soon as the idea that the speed of light is finite was accepted, the speed * time=distance formula was obvious.

Answer 7

Me mate Len was pissed and he found the first ever one on Dunc's head but then I realized it was the shine off the sun behind his head or something like that I think

Answer 8

When Thomas Edison had celebrated the 1st anniversary of his light bulb , I guess. =)

Answer 9

it was not invented, it was devised as a system of measurement for vast distances

Answer 10

check the web:
www.ebizel.com