Technical name for 'day' on other planets

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In summary, the technical term for a "Lunar day-night cycle" (28 Earth days) has been a topic of discussion as it is often referred to as a "sol" or "month." However, after some research, it has been suggested that the term "molad" could be used, which comes from the Hebrew calendar and is based on virtual lunar conjunctions called "molads" spaced precisely 29 days, 12 hours, and 793 parts apart. Other alternatives include "synod" or simply "month." However, it should be noted that the term "sol" is commonly used to refer to the Martian day and could potentially apply to any planet. Other cultural references, such as "lune" or "
  • #1
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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  • #2
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
 
  • #3
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
 
  • #4
People call the Martian day a "sol." I think the world "sol" could apply equally well to any planet.

- Warren
 
  • #5
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:
 
  • #6
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:
 
  • #7
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! :tongue:
Fine. BE picky, then. :tongue: :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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1. What is the technical name for 'day' on other planets?

The technical term for 'day' on other planets is sol.

2. How is sol different from a day on Earth?

Sol is the term used to describe a full rotation of a planet on its axis. On Earth, this takes approximately 24 hours, but on other planets it can vary greatly. For example, a sol on Mars is approximately 24 hours and 39 minutes, while a sol on Venus is about 243 Earth days.

3. Is the length of a sol consistent on all planets?

No, the length of a sol varies depending on the planet's rotation speed. Some planets have longer or shorter days than Earth, and some planets even have multiple 'days' in one Earth day.

4. Can we use the same units to measure sol on all planets?

Yes, we can use the same units to measure sol on all planets. However, the numerical value will be different due to the varying lengths of a sol on different planets. For example, we can measure a sol on Mars in hours and minutes, just like we measure a day on Earth.

5. Why is it important to have a technical term for 'day' on other planets?

Having a technical term like sol allows scientists to communicate accurately and efficiently about time measurements on other planets. It also helps us understand the unique characteristics of different planets and how they relate to our own planet.

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