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How far is a lightyear?
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Caviar Liberta
The Scope
Gallente Federation
#61 - 2014-05-08 19:58:48 UTC  |  Edited by: Caviar Liberta
Picture

The picture is from a jump planner for a jump from Pelille to Vlillirier. The jump planer says this is a distance of 9.26 light years.

Hope this gives an idea of the distance a light year covers.
James Nikolas Tesla
Tesla Holdings
#62 - 2014-05-08 19:59:25 UTC
Serene Repose wrote:
I can't believe Tesla asked this question. This has to be a troll thread.

Well, I did ask and this is not a troll thread (at least on my part)

Anyhow, thank you to the people that helped me out, it turns out I was missing a part and I found some helpful tools for future use.

CODE is just a bunch of pirates; smart, organized pirates. It doesn't help to rage at them because that is exactly what they want. Dust yourself off and get back on your feet, you don't even have to talk to them.
James Amril-Kesh
Viziam
Amarr Empire
#63 - 2014-05-08 20:03:30 UTC
Solecist Project's Alt wrote:
Ramona McCandless wrote:
Oh ok. Sorry.

I thought that the passage of time appeared to be altered the closer to the speed of light you reached, therefore the length of time to travel the sdistance would vary depending if you were the subject or the object.

I really am trying to remember this stuff from school, so Ill take your word for it :)

http://www.reddit.com/r/explainlikeimfive/comments/22pi7o/eli5_why_does_light_travel/

This might be interesting for you.

It's not for those who believe they can read things and understand it immediately.


Great read.


A relevant part regarding time dilation:
Quote:
By the way, this is why time dilation happens: something that's moving very fast relative to you is moving through space, but since they can only travel through spacetime at c, they have to be moving more slowly through time to compensate (from your point of view).

That actually clarified things significantly for me as well.

Enjoying the rain today? ;)
Evelyn Meiyi
Corvidae Trading and Holding
#64 - 2014-05-08 20:28:04 UTC
Ramona McCandless wrote:
Oraac Ensor wrote:


Exactly how far is a lightyear? I assume it is one jump


Uh huh. And this is a sensible, non-idiotic question that cant be looked up in seconds, quineg?


I'd expect a mech pilot to be polite, instead of bickering like a six-year-old. Quiaff?
Ion Kirst
KIRSTONE ALLIANCE
#65 - 2014-05-08 21:05:01 UTC  |  Edited by: Ion Kirst
Ok guys some of this is basic physics, some of this other stuff that was touched upon borders into Quantum mechanics.

Light travels at 186,000 miles per second. A light year is the distance light will travel in one year.

An A. U. is the distance between the Earth and the Sun, that's about 93 million miles. I believe it takes about 8 to 9 minutes for light to travel from the Sun to the Earth.

In Eve a ship can make a jump much farther than one A.U.

In a vacuum, light travels at the same speed, until it passes thru something that slows down the different colors that "white" light is made of. Red light travels more quickly (thru glass) than does violet light. When light passes thru a prism, the white light is broken down into all it's colors. ( a rainbow)

If there is a star behind a black hole in space, it's light sometimes can be seen as the gravitational forces of the black hole bend that light. (Sky and Telescope Mag. has some pictures.)

Could say more, but I've said too much. Science is just cool, and EVE tries to actually use some of it.

-Kirst

Always remember Tovil-Toba, and what was done there.
James Amril-Kesh
Viziam
Amarr Empire
#66 - 2014-05-08 21:16:44 UTC
1 AU is about 8.32 light minutes (.32 minutes ~= 19 seconds).
As said earlier, light doesn't travel slower in a medium, what happens is that it's absorbed (photon energy excites a valence electron in the material) and re-emitted some time later (excited electron releases its energy in the form of a photon to return to the base energy state).
And again, light doesn't actually bend. Light always travels in a straight path. The space that the light is traveling through is curved.

Enjoying the rain today? ;)
Ion Kirst
KIRSTONE ALLIANCE
#67 - 2014-05-08 22:27:43 UTC
James hope you didn't think I was saying your wrong, because I wasn't.



"A gravitational lens refers to a distribution of plates (such as a cluster of galaxies) between a distant source (a background galaxy) and an observer, that is capable of bending (lensing) the light from the source, as it travels towards the observer. This effect is known as gravitational lensing and is one of the predictions of Albert Einstein's general theory of relativity."

"Spacetime around a massive object (such as a galaxy cluster or a black hole) is curved, and as a result light rays from a background source (such as a galaxy) propagating through spacetime are bent. The lensing effect can magnify and distort the image of the background source."

"Unlike an optical lens, maximum 'bending' occurs closest to, and minimum 'bending' furthest from, the center of a gravitational lens. Consequently, a gravitational lens has no single focal point, but a focal line instead. If the (light) source, the massive lensing object, and the observer lie in a straight line, the original light source will appear as a ring around the massive lensing object. If there is any misalignment the observer will see an arc segment instead."

I remember seeing a great picture of this in S&T, but I could find the article. I wanted to copy and paste what was said, and to be on the safe side, I'm quoting from another source.

In all, it's a great discussion.

-Kirst


Always remember Tovil-Toba, and what was done there.
Kryxal
Wing Born Echos
#68 - 2014-05-09 02:24:34 UTC
James Nikolas Tesla wrote:
Well, I did ask and this is not a troll thread (at least on my part)

Anyhow, thank you to the people that helped me out, it turns out I was missing a part and I found some helpful tools for future use.


Remote Sensing isn't worth much, by the way ... you might as well just go to the system and look. If it's low-sec, take a covops. Assuming you're doing this for PI, any planet you place a command center on is effectively range 0 anyway.
Sir Substance
Sebiestor Tribe
Minmatar Republic
#69 - 2014-05-09 03:46:33 UTC
1 lightyear is 3.066x10^17 attoparsecs, or 5.559x10^15 smoots.

I hope this clears up the issue for you.

The beatings will continue until posting improves. -Magnus Cortex

Official Eve Online changelist: Togglable PvP. - Jordanna Bauer
Hasikan Miallok
Republic University
Minmatar Republic
#70 - 2014-05-09 03:54:29 UTC
James Amril-Kesh wrote:
1 AU is about 8.32 light minutes (.32 minutes ~= 19 seconds).
As said earlier, light doesn't travel slower in a medium, what happens is that it's absorbed (photon energy excites a valence electron in the material) and re-emitted some time later (excited electron releases its energy in the form of a photon to return to the base energy state).
And again, light doesn't actually bend. Light always travels in a straight path. The space that the light is traveling through is curved.



Regardless of the process involved, they slowed it down to effectively travel at 38 mph in some sort of supercooled gas back in the 90's no idea if there was any progress on that record.

http://www.news.harvard.edu/gazette/1999/02.18/light.html
James Amril-Kesh
Viziam
Amarr Empire
#71 - 2014-05-09 03:58:31 UTC
They can stop it entirely now.

Enjoying the rain today? ;)
Cebraio
State War Academy
Caldari State
#72 - 2014-05-09 09:22:45 UTC
James Amril-Kesh wrote:
They can stop it entirely now.

The article for five year olds: http://www.geekosystem.com/light-trapped/

Also contains a link to a more detailed article and the actual paper.
Octoven
Stellar Production
#73 - 2014-05-09 11:17:03 UTC
This is one thing I actually wished they would add to the map somehow. A light year is not one jump though. Some gates will jump you 8 light years and some 1/10th it just varies. The only sure fire way to know is grab a ship with a jump drive, know its current jump range, pull up the map and there ya go, you can kind of sort of estimate. You will be surprised though how many systems are under 1 light year from each other...eve is one hell of a densely packed cluster of stars.
ctx2007
Republic Military School
Minmatar Republic
#74 - 2014-05-10 10:18:15 UTC
In RL a light year is roughly a quarter way to Alpha centauri, our nearest neighbour 4.37ly

You only realise you life has been a waste of time, when you wake up dead.
Ion Kirst
KIRSTONE ALLIANCE
#75 - 2014-05-10 20:35:20 UTC
ctx2007 wrote:
In RL a light year is roughly a quarter way to Alpha centauri, our nearest neighbour 4.37ly



Yes, so if you could travel at the speed off light, it would take you 4.37 years to reach Alpha Centauri. (or you could get lost in space.)

-Kirst

Always remember Tovil-Toba, and what was done there.
Mr Epeen
It's All About Me
#76 - 2014-05-11 02:25:23 UTC
If I wanted to get to the Andromeda galaxy (approx 2.5m ly), how many jumps would I have to make in a tricked out, max skilled, jump freighter?

Mr Epeen Cool
James Amril-Kesh
Viziam
Amarr Empire
#77 - 2014-05-11 02:50:31 UTC
Mr Epeen wrote:
If I wanted to get to the Andromeda galaxy (approx 2.5m ly), how many jumps would I have to make in a tricked out, max skilled, jump freighter?

Mr Epeen Cool

Assuming 2,500,000 LY exactly:
A Nomad (most fuel efficient freighter) at JDC 5 has to make 222,223 jumps, consuming about 1,687,500,000 hydrogen isotopes at JFC 5 and JF 5. You'd need a little over 1/4 of a cubic kilometer of fuel (250,000,000 m3).

An interesting exercise would be to see how many jump freighters full of fuel you'd need to get one jump freighter all the way across, but I don't feel like doing that math right now (and I'm not entirely sure how I'd set up that problem).

Enjoying the rain today? ;)
Utremi Fasolasi
La Dolce Vita
#78 - 2014-05-11 05:30:40 UTC
OP - try New Citizens Q &A for this time of game mechanics question next time - it's a bit less of a piranha pool over there and more like swimming with dolphins.
BrundleMeth
State War Academy
Caldari State
#79 - 2014-05-11 10:20:19 UTC
Zifrian wrote:
http://lmgtfy.com/?q=how+far+is+a+light+year



When I clicked on that all I saw was 2 Donkey's and a farm girl...
Bob Maths
Federal Navy Academy
Gallente Federation
#80 - 2014-05-11 11:31:08 UTC  |  Edited by: Bob Maths
James Amril-Kesh wrote:
1 AU is about 8.32 light minutes (.32 minutes ~= 19 seconds).
As said earlier, light doesn't travel slower in a medium, what happens is that it's absorbed (photon energy excites a valence electron in the material) and re-emitted some time later (excited electron releases its energy in the form of a photon to return to the base energy state).
And again, light doesn't actually bend. Light always travels in a straight path. The space that the light is traveling through is curved.


Not necessarily correct and we're arguing pedantics here.

Light doesn't excite exclusively valence electrons, as valence electrons are ones of the highest energy state, requiring the least energy to be emitted and are absorbed if the photon is of the hf to release the electron. The photoelectric effect tells us that the energy of the photon only needs to be greater than the difference of next energy state to the highest energy state for emission to occur.

As most mediums compared to the path of trajectory of a photon is virtually non-existent if it is opaque. The speed of light c is derived from Maxwell's equations (as all physicists should know) and is ultimately the inverse square root of the product of the permeability and permittivity of free space. However, that is free space. All mediums other than free space (a vacuum) have a refractive index which is a proportional increase of what the speed of light in the medium needs be multiplied by to become c. So as a result the permeability and permittivity of any other medium will reduce the speed to v, a percentage of c.

Light doesn't bend but space does so it doesn't bend? So, a projectile doesn't bend towards the Earth, the Earth is being pulled upwards in such a fashion that the projectile appears to be bending towards it. Oh wait, anyone who does physics knows that all masses attract each other so actually that's right, if only by thousandths of the radius of a nucleon in the case of Earth-to-Projectile. Classical mechanics will tell us that the projectile follows a parabolic motion towards the surface much quicker than the Earth will rotate and adjust itself to the point of the projectile. Light does bend as the path is bent and it can only travel along spacetime which begs the nature of light.


Ion Kirst wrote:

Yes, so if you could travel at the speed off light, it would take you 4.37 years to reach Alpha Centauri. (or you could get lost in space.)

-Kirst



No it would not. Relativity will tell us that it will take less 'time' for you to reach Alpha Centauri but why waste all the energy going up to the speed of light when you could just warp and get there sooner?

When considering time dilation you have to also take into account length stretching (or from your point of view, length contraction) of the object in question that is travelling to the speed of light. The reason (i imagine, not versed as much as a msci in this) is because as you travel to the speed of light you occupy all the space of the event within the time period of observation and thus you appear to be stretched.

Length contraction means that your journey will mechanically take less time from your clock than if you were to sit and observe the journey. There would be a disparity in clock time ticking.

This is one of the reasons why we can observe muons at ground level and also how matter from the start of the universe are only just arriving here.


To answer the main post if it hasn't been answered already:
9.4605284 × 10^15 m in standard form which is 9.4 trillion (or billion if you like the long scale) km, so think travelling for 6 hours at 3 AUs