Technical name for 'day' on other planets

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Discussion Overview

The discussion revolves around the search for a technical term to describe the lunar day-night cycle, which lasts approximately 28 Earth days. Participants explore various naming conventions and terms that could be used to avoid confusion with existing terminology.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • Some participants express concern that "Lunar Day" may be misunderstood as the 14-day period of sunlight on the Moon.
  • One participant suggests using "sol" as a term, although they note it may not be widely recognized for lunar contexts.
  • Another participant mentions "molad," a term used in Hebrew calendars for lunar conjunctions, and highlights its appeal.
  • Several terms related to lunar cycles are discussed, including "siderial period," "synodical month," "tropical month," "anomalistic month," and "nodical month," with suggestions to use "synod" as a shorthand for "synodical month."
  • There is a playful discussion about the term "month," with some suggesting it could derive from "moon," and others proposing "lune" or "moonth" as alternatives.
  • One participant emphasizes the importance of using the correct terminology in professional settings, particularly when presenting to NASA representatives.

Areas of Agreement / Disagreement

Participants do not reach a consensus on a single term to use, with multiple competing suggestions and preferences expressed throughout the discussion.

Contextual Notes

There are unresolved assumptions regarding the appropriateness and recognition of the proposed terms in various contexts, including professional and cultural considerations.

enigma
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Does anyone know if there is a (short) technical name for a "Lunar day-night cycle" (28 Earth days)?

We're afraid that simply saying "Lunar Day" might be misconstrued as the 14 day period which a site would be in the sun, and typing "Lunar day-night cycle" is becoming rediculous when it needs to be referenced several times in one paragraph.

We've been calling it a "sol", but I don't think that's a typical term.
 
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I looked around a bit and saw other people struggling with the same problem. I saw either day/night cycle, lunar day, or if you plan to publish in Hebrew, a molad.

The calendar is based on virtual lunar conjunctions called "molads" spaced precisely 29 days, 12 hours, and 793 parts apart

http://en.wikipedia.org/wiki/Hebrew_calendar
 
Ivan Seeking said:
I looked around a bit and saw other people struggling with the same problem. I saw either day/night cycle, lunar day, or if you plan to publish in Hebrew, a molad.

The calendar is based on virtual lunar conjunctions called "molads" spaced precisely 29 days, 12 hours, and 793 parts apart

http://en.wikipedia.org/wiki/Hebrew_calendar

molad has a really nice sound
this last post shows editorial flair. the kerry quote is well chosen from among many possible things that could have had similar impact
the finding of "molad" is like a small prize for Ivan having done the "seeking"
research----editors of magazines do a lot of fact-checking in obscure references, if they are good. it has this flavor. You could edit a small science-related magazine that would be interesting or attract a following, or a blog.

to toss in some more arcana, my astrophysics handbook lists several months

siderial period----around 27.3
synodical month-----what you call molad, new moon to new moon
tropical month-----around 29.3
anomalistic month----perigee to perigee
nodical month------node to node


This suggests to me that one alternative to saying "molad" would be
to say "synod"
as a shortening of "synodical month"

but what would really be wrong with simply saying "month"
it must come from moon because it sounds like "moonth"
probably there are some people who say "lune" for the 29.5 earthday period
regards to Tsu
 
People call the Martian day a "sol." I think the world "sol" could apply equally well to any planet.

- Warren
 
marcus said:
molad has a really nice sound
this last post shows editorial flair. the kerry quote is well chosen from among many possible things that could have had similar impact
the finding of "molad" is like a small prize for Ivan having done the "seeking"
research----editors of magazines do a lot of fact-checking in obscure references, if they are good. it has this flavor. You could edit a small science-related magazine that would be interesting or attract a following, or a blog.

to toss in some more arcana, my astrophysics handbook lists several months

siderial period----around 27.3
synodical month-----what you call molad, new moon to new moon
tropical month-----around 29.3
anomalistic month----perigee to perigee
nodical month------node to node


This suggests to me that one alternative to saying "molad" would be
to say "synod"
as a shortening of "synodical month"

but what would really be wrong with simply saying "month"
it must come from moon because it sounds like "moonth"
probably there are some people who say "lune" for the 29.5 earthday period
regards to Tsu
Thanks, Marcus! Back at ya! (sure wish I had spent less time on my professional CE and more on LQG now that Rovelli and Baez have visited! :wink: Dang! Don't let them get away! :biggrin: )

I thing molad has a very nice ring to it. (could be a function of my Jewish ancestry :wink: )

Synod - sounds like a religious ecclesiastical council... :eek:

Lune? - hey! you talkin' 'bout me again?

Moonth - hmmmm... it has certain possibilities...

If this is a democratic thread, I vote for molad. :biggrin:
 
Tsunami said:
If this is a democratic thread, I vote for molad. :biggrin:

Well, there will be some NASA bigwigs at the comprehensive design review for my senior design class. Don't want to sound like an idiot at that presentation or in the project writeup. :cool:
 
enigma said:
Well, there will be some NASA bigwigs at the comprehensive design review for my senior design class. Don't want to sound like an idiot at that presentation or in the project writeup. :cool:
Hey! Whose ancestral language are you calling idiotic! :-p
Fine. BE picky, then. :-p :biggrin:
If you don't like Hebrew, would Hindu be more acceptable?

http://www.encyclopedia4u.com/t/tithi.html

This assumes, of course, that the NASA bigwigs are into vedic timekeeping... :wink:
 
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