# Radio-only communications with Aliens: left and right? -- Updates? **URL:** \ **Category:** Miscellaneous and Personal Stuff I Must Share\ **Created:** [June 28, 2011, 5:14pm UTC](https://boards.straightdope.com/t/radio-only-communications-with-aliens-left-and-right-updates/587159 "2011-06-28T17:14:27Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![Zeldar](https://avatars.discourse-cdn.com/v4/letter/z/b77776/32.png) [@Zeldar](https://boards.straightdope.com/u/Zeldar)\ **Post date:** [June 28, 2011, 5:14pm UTC](https://boards.straightdope.com/t/radio-only-communications-with-aliens-left-and-right-updates/587159/1 "2011-06-28T17:14:27Z")
> **[Radio-only communications with Aliens: left and right?](https://boards.straightdope.com/sdmb/showthread.php?t=330236)** > > I know there was a thread on this topic, but I don’t remember any keywords that search would recognize. So if you can point to the old thread, great. The issue was/is: if all we had to communicate with some alien civilization was radio, how could we... Radio-only communications with Aliens: left and right? (Was started 08-15-2005, 07:54 AM and got 6 posts through 08-15-2005, 06:55 PM ) Are there other threads on the topic? The recent East-West thread got me thinking that I never got a convincing explanation of the Left-Right issue and kept me wondering if the two issues aren’t really much the same. Ideas? Answers? Bump the zombie or reply here. Whatever is best. ---
**Author:** ![Zeldar](https://avatars.discourse-cdn.com/v4/letter/z/b77776/32.png) [@Zeldar](https://boards.straightdope.com/u/Zeldar)\ **Post date:** [June 28, 2011, 7:31pm UTC](https://boards.straightdope.com/t/radio-only-communications-with-aliens-left-and-right-updates/587159/2 "2011-06-28T19:31:28Z")
This can’t be the thread I was mentioning in the one linked to in the OP, since it came later: > **[Define "left".](https://boards.straightdope.com/sdmb/showthread.php?t=409520)** > > I saw something on TV a while back - someone suggested that you can’t define “left” or “right” only using words. The other people on the show couldn’t think of a way. I couldn’t think of a way (Other than “That way” points) So, I went looking to see... Define “left”. 02-22-2007, 09:18 AM through 02-22-2007, 03:13 PM for 31 posts ---
**Author:** ![Zeldar](https://avatars.discourse-cdn.com/v4/letter/z/b77776/32.png) [@Zeldar](https://boards.straightdope.com/u/Zeldar)\ **Post date:** [June 29, 2011, 2:25pm UTC](https://boards.straightdope.com/t/radio-only-communications-with-aliens-left-and-right-updates/587159/3 "2011-06-29T14:25:43Z")
From the revived … > **[Define "left".](https://boards.straightdope.com/sdmb/showthread.php?t=409520)** > > I saw something on TV a while back - someone suggested that you can’t define “left” or “right” only using words. The other people on the show couldn’t think of a way. I couldn’t think of a way (Other than “That way” points) So, I went looking to see... Define “left”. Started 02-22-2007, 09:18 AM by **Revenant Threshold** In [this post](http://boards.straightdope.com/sdmb/showpost.php?p=13968943&postcount=37) > [@Peter Morris](#): > > Today, 08:47 AM > > [Quote=Zeldar] > Some other stabs at answers to this question showed up in Radio-only communications with Aliens: left and right? Assuming that aliens have a similar biology to us, and a similar level of technology and science: Shine white light through a prism. The white light will be split into bands of colour. Stand facing the prism. Blue is the left side of the spectrum, red is the right side. If aliens don’t understand what ‘blue’ and ‘red’ are, explain in terms of the Doppler shift. [/quote] … comes very close to convincing me of a way that would work and which ought to translate to another alien civilization’s capabilities. The only real issue, as I see it, is whether our assumptions about the nature of Light and Optics are universal. At present I would vote for it. (Just wanted this thread to have the opportunity to discuss the topic more. Either here or on the linked thread suits me fine.)