# Lightyears and Parsecs **URL:** \ **Category:** Factual Questions\ **Created:** [December 3, 2014, 3:16am UTC](https://boards.straightdope.com/t/lightyears-and-parsecs/706192 "2014-12-03T03:16:11Z")\ **Posts on this page:** 18\ **Page:** 2
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [December 5, 2014, 10:12pm UTC](https://boards.straightdope.com/t/lightyears-and-parsecs/706192/21 "2014-12-05T22:12:25Z")
> [@buddha\_david](#): > > Unless you’re[Joan Baez.](https://www.youtube.com/watch?v=1ST9TZBb9v8) It’s a science fiction song… ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [December 6, 2014, 5:08am UTC](https://boards.straightdope.com/t/lightyears-and-parsecs/706192/22 "2014-12-06T05:08:21Z")
> [@](#): > > Quoth **md2000** : > > Except that you’d add the ambiguity of mass. Doesn’t light technically red-shift due to gravity too? True in principle, but not a problem in practice. Any plausible source at that kind of distance will have a gravitational redshift that’s negligible compared to its cosmological redshift. ---
**Author:** ![Napier](https://avatars.discourse-cdn.com/v4/letter/n/ce73a5/32.png) [@Napier](https://boards.straightdope.com/u/Napier)\ **Post date:** [December 6, 2014, 12:19pm UTC](https://boards.straightdope.com/t/lightyears-and-parsecs/706192/23 "2014-12-06T12:19:19Z")
> [@Chronos](#): > > Even if we knew the redshift-distance relation exactly, it’d still be a good idea to express cosmological distances as redshifts, because on that scale, there are multiple different ways to define distance, and stating the redshift removes the ambiguity. Right, good point, I was forgetting. Absolutely. And I still never quite grasped all the ways; I remember some involved conceptually difficult distinctions, for me. ---
**Author:** ![Hail\_Ants](https://avatars.discourse-cdn.com/v4/letter/h/dc4da7/32.png) [@Hail\_Ants](https://boards.straightdope.com/u/Hail_Ants)\ **Post date:** [December 6, 2014, 5:01pm UTC](https://boards.straightdope.com/t/lightyears-and-parsecs/706192/24 "2014-12-06T17:01:20Z")
> [@leahcim](#): > > Of course, in the expanded universe there is a whole explanation involving clusters of black holes and nav computers that make what Han said technically correct (the best kind of correct!). I saw the original Star Wars in the theater in ‘77 and even though I was only 11 years old I was such a science geek I caught that mistake the instant Ford said it. I even remember an article in the old magazine \*Starlog \*which tried to make some ridiculous convoluted explanation about hyperspace warping space and therefore making a parsec ‘less’. Amusing once I was old enough to fully realize it was just Lucas’ shitty writing! 😃 ---
**Author:** ![Derleth](https://avatars.discourse-cdn.com/v4/letter/d/b9e5f3/32.png) [@Derleth](https://boards.straightdope.com/u/Derleth)\ **Post date:** [December 6, 2014, 8:01pm UTC](https://boards.straightdope.com/t/lightyears-and-parsecs/706192/25 "2014-12-06T20:01:52Z")
> [@ZenBeam](#): > > It’s a science fiction song… Good science fiction gets the facts right, as far as they apply to the story. I mean, if we don’t allow Lucas to get away with shit… ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [December 6, 2014, 8:09pm UTC](https://boards.straightdope.com/t/lightyears-and-parsecs/706192/26 "2014-12-06T20:09:17Z")
sigh ---
**Author:** ![Derleth](https://avatars.discourse-cdn.com/v4/letter/d/b9e5f3/32.png) [@Derleth](https://boards.straightdope.com/u/Derleth)\ **Post date:** [December 6, 2014, 10:52pm UTC](https://boards.straightdope.com/t/lightyears-and-parsecs/706192/27 "2014-12-06T22:52:39Z")
> [@ZenBeam](#): > > sigh What? Annoyed a songwriter is getting taken to task for the same reason a screenwriter/director is? ---
**Author:** ![EdwinAmi](https://avatars.discourse-cdn.com/v4/letter/e/5fc32e/32.png) [@EdwinAmi](https://boards.straightdope.com/u/EdwinAmi)\ **Post date:** [December 7, 2014, 12:56am UTC](https://boards.straightdope.com/t/lightyears-and-parsecs/706192/28 "2014-12-07T00:56:56Z")
I didn’ even realize parsec is a realunit of distance Still doesn’t explain why George Lucas made Han Solo say the millenium falcon “made the kessel run in 12 parsecs” ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [December 7, 2014, 1:05am UTC](https://boards.straightdope.com/t/lightyears-and-parsecs/706192/29 "2014-12-07T01:05:04Z")
> [@EdwinAmi](#): > > I didn’ even realize parsec is a realunit of distance > > Still doesn’t explain why George Lucas made Han Solo say the millenium falcon “made the kessel run in 12 parsecs” Nor does it explain why you didn’t bother to read the whole thread before posting. ---
**Author:** ![md2000](https://avatars.discourse-cdn.com/v4/letter/m/73ab20/32.png) [@md2000](https://boards.straightdope.com/u/md2000)\ **Post date:** [December 7, 2014, 6:53am UTC](https://boards.straightdope.com/t/lightyears-and-parsecs/706192/30 "2014-12-07T06:53:06Z")
> [@Hail\_Ants](#): > > I saw the original Star Wars in the theater in ‘77 and even though I was only 11 years old I was such a science geek I caught that mistake the instant Ford said it. I even remember an article in the old magazine \*Starlog \*which tried to make some ridiculous convoluted explanation about hyperspace warping space and therefore making a parsec ‘less’. Amusing once I was old enough to fully realize it was just Lucas’ shitty writing! 😃 yeah. I was disappointed. The whole rest of the first movie appeared to show a deeper understanding of the universe. Unlike Space1999 or Lost in Space or even Firefly, or any “memorable” Hollywood fluff - Lucas seemed to realize that planets orbit star systems, moons orbit planets, and star systems are so incredibly far apart and isolated that you can’t get between them without hyperdrive. And meanwhile he blows it with such an obvious mistake. And then Kershner blew it completely with TESB(V), despite having Leigh Brackett as the writer for that one. Sorry, going from star system to star system without hyperdrive is like “I’ll just slip out the back door and walk over to Paris for the afternoon.” > [@EdwinAmi](#): > > I didn’ even realize parsec is a realunit of distance > > Still doesn’t explain why George Lucas made Han Solo say the millenium falcon “made the kessel run in 12 parsecs” Amateur with no science knowledge. Like you, he’d heard the term and assumed “sec” = “seconds” = time. Like people who think a silencer on a gun actually silences it. Like Hollywood people who think you can outrun an explosion for a while like many bad action movies since digital effects came along. Like Hollywood people who think you can fall 10 feet then grab hold by your fingertips to a ledge in an elevator shaft and hold on…(Die Hard) Sometimes it’s just ignorance, sometimes its willful ignorance, and sometimes it’s just negligence. ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [December 7, 2014, 1:05pm UTC](https://boards.straightdope.com/t/lightyears-and-parsecs/706192/31 "2014-12-07T13:05:58Z")
> [@Derleth](#): > > What? Annoyed a songwriter is getting taken to task for the same reason a screenwriter/director is? Annoyed that someones getting all worked up over a joke. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [December 7, 2014, 7:25pm UTC](https://boards.straightdope.com/t/lightyears-and-parsecs/706192/32 "2014-12-07T19:25:29Z")
Who went from one star system to another without a hyperdrive in ESB? ---
**Author:** ![D18](https://avatars.discourse-cdn.com/v4/letter/d/c57346/32.png) [@D18](https://boards.straightdope.com/u/D18)\ **Post date:** [December 7, 2014, 8:29pm UTC](https://boards.straightdope.com/t/lightyears-and-parsecs/706192/33 "2014-12-07T20:29:34Z")
Going from memory: weren’t we told X-wing fighters didn’t go faster than light, but Luke had to do just that to get from Yoda’s planet to wherever he went after that? ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [December 7, 2014, 8:59pm UTC](https://boards.straightdope.com/t/lightyears-and-parsecs/706192/34 "2014-12-07T20:59:19Z")
X-wings have hyperdrives. It’s TIE fighters that don’t. ---
**Author:** ![buddha\_david](https://avatars.discourse-cdn.com/v4/letter/b/ee7513/32.png) [@buddha\_david](https://boards.straightdope.com/u/buddha_david)\ **Post date:** [December 7, 2014, 9:03pm UTC](https://boards.straightdope.com/t/lightyears-and-parsecs/706192/35 "2014-12-07T21:03:03Z")
> [@Chronos](#): > > Who went from one star system to another without a hyperdrive in ESB? How do we know the stars weren’t much closer together in that galaxy? ---
**Author:** ![D18](https://avatars.discourse-cdn.com/v4/letter/d/c57346/32.png) [@D18](https://boards.straightdope.com/u/D18)\ **Post date:** [December 7, 2014, 10:34pm UTC](https://boards.straightdope.com/t/lightyears-and-parsecs/706192/36 "2014-12-07T22:34:16Z")
> [@Chronos](#): > > X-wings have hyperdrives. It’s TIE fighters that don’t. Huh. I’ve been under this misapprehension for decades, then. Is there any way that the novelization of Ep IV would have said otherwise? I could have sworn that there was something along those lines. ---
**Author:** ![Nancarrow](https://avatars.discourse-cdn.com/v4/letter/n/c37758/32.png) [@Nancarrow](https://boards.straightdope.com/u/Nancarrow)\ **Post date:** [December 8, 2014, 2:47am UTC](https://boards.straightdope.com/t/lightyears-and-parsecs/706192/37 "2014-12-08T02:47:32Z")
> [@buddha\_david](#): > > How do we know the stars weren’t much closer together in that galaxy? Because in that galaxy, we could clearly see that people were ALIVE. ---
**Author:** ![leahcim](https://avatars.discourse-cdn.com/v4/letter/l/b4bc9f/32.png) [@leahcim](https://boards.straightdope.com/u/leahcim)\ **Post date:** [December 8, 2014, 3:14am UTC](https://boards.straightdope.com/t/lightyears-and-parsecs/706192/38 "2014-12-08T03:14:39Z")
> [@Nancarrow](#): > > Because in that galaxy, we could clearly see that people were ALIVE. Are you implying that people couldn’t survive in a galaxy where the stars were much closer together? The earth is eight light-minutes from the sun. Neptune is about four light-hours from the sun. I’d think that if the next star over was light-weeks away instead of light-years away you wouldn’t see too much disruption in the inner solar system in the short term. The closer encounters might prevent orbits from being stable for the amount of time required for life to evolve, but in the star wars galaxy, no species is native to the planet they hang out on anyway. [Previous page](https://boards.straightdope.com/t/lightyears-and-parsecs/706192.md?page=1)