Question about the full moon

I know nothing about astronomy, but I have a dispute which someone here
might be able to settle for me:

When it's a full moon in the UK, is it also a full moon in all other parts
of the world at around the same time, or does it vary according to latitude
ot longitude?

--
Hungerdunger
To reply by email, remove the MARX from my address

In article <epbbcl$47m$1$8300dec7@news.demon.co.uk>,
Hungerdunger <Hungerdunger@celynnen.MARXdemon.co.uk> wrote:

>When it's a full moon in the UK, is it also a full moon in all other parts
>of the world at around the same time, or does it vary according to latitude
>ot longitude?

It's a full moon when the side of the moon facing the earth is
illuminated by the sun. The side of the moon facing on point on the
earth is very slightly different from that facing another point, so
it's possible for the moon to be full as seen from one place but very
slightly un-full from another, but the difference is so small as to be
unnoticable in practice.

-- Richard

--
"Consideration shall be given to the need for as many as 32 characters
in some alphabets" - X3.4, 1963.

"Hungerdunger" <Hungerdunger@celynnen.MARXdemon.co.uk> wrote in
news:epbbcl$47m$1$8300dec7@news.demon.co.uk:

> I know nothing about astronomy, but I have a dispute which someone here
> might be able to settle for me:
>
> When it's a full moon in the UK, is it also a full moon in all other
> parts of the world at around the same time, or does it vary according to
> latitude ot longitude?
>

The moon is full everywhere at the same time for casual observation. There
will be a small difference just because of the different position that
viewers are looking from. I believe the official definition of full moon is
when the moon's ecliptic longitude is exactly 180 degrees different to the
Sun. Half of the Earth cannot see this exact event because it is daytime
for that half ;-). As the Moon's orbit is inclined to the ecliptic you
could argue that a 'true' full Moon is impossible, as when the Moon is
exactly opposite the Sun in 3D it is in the Earth's shadow (lunar eclipse)
and thus not illuminated except by stray light refracted/scattered by the
Earth's atmosphere.

Klazmon

A think 'full moon' is a sort of non-scientific term.

A more precise term is opposition. That is the instant that the moon is
directly on the opposite side of the earth from the sun. Opposition is at
the same time wherever you are located on the earth.

Cheers
Paul
"Hungerdunger" <Hungerdunger@celynnen.MARXdemon.co.uk> wrote in message
news:epbbcl$47m$1$8300dec7@news.demon.co.uk...
>I know nothing about astronomy, but I have a dispute which someone here
>might be able to settle for me:
>
> When it's a full moon in the UK, is it also a full moon in all other parts
> of the world at around the same time, or does it vary according to
> latitude ot longitude?
>
> --
> Hungerdunger
> To reply by email, remove the MARX from my address
>

"Paul Clark" <dr.clark@dial.pipex.com> wrote in message
news:SqudncOtPoXEzyfYRVnyvgA@pipex.net...
>A think 'full moon' is a sort of non-scientific term.
>
> A more precise term is opposition. That is the instant that the moon is
> directly on the opposite side of the earth from the sun. Opposition is at
> the same time wherever you are located on the earth.

Thank you, everyone, for your replies.

I thought I'd get a sensible answer here.
--
Hungerdunger
To reply by email, remove the MARX from my address

> Paul"Hungerdunger" <Hungerdun...@celynnen.MARXdemon.co.uk> wrote in messagenews:epbbcl$47m$1$8300dec7@news.demon.co.uk ...
>
> >I know nothing about astronomy, but I have a dispute which someone
> > here might be able to settle for me:
>
> > When it's a full moon in the UK, is it also a full moon in all other parts
> > of the world at around the same time, or does it vary according to
> > latitude or longitude?

Ignorant and/or lazy poster:
On Jan 26, 7:11 pm, "Paul Clark" <dr.cl...@dial.pipex.com> top posted:
<corrected>
> A think 'full moon' is a sort of non-scientific term.
>
> A more precise term is opposition. That is the instant that the moon is
> directly on the opposite side of the earth from the sun. Opposition is at
> the same time wherever you are located on the earth.

It takes something like 30 hours for the percentage visibility to go
from 99% through 100% (full) to 99% again. So the moon will appear
full for almost everyone on the planet.

It can seem to be full for two transits on occasion. A transit to
transit is a "tidal day" of just over 24 hours and 50 or 55 minutes,
IIRC.

It takes something like 20 hours for the moon to go from 1% visibility
through new moon to 1% again.

(Or is that the times for half percentages I remember?)

	#1
Hungerdunger	Question about the full moon I know nothing about astronomy, but I have a dispute which someone here might be able to settle for me: When it's a full moon in the UK, is it also a full moon in all other parts of the world at around the same time, or does it vary according to latitude ot longitude? -- Hungerdunger To reply by email, remove the MARX from my address

	#2
Richard Tobin	Re: Question about the full moon In article <epbbcl$47m$1$8300dec7@news.demon.co.uk>, Hungerdunger <Hungerdunger@celynnen.MARXdemon.co.uk> wrote: >When it's a full moon in the UK, is it also a full moon in all other parts >of the world at around the same time, or does it vary according to latitude >ot longitude? It's a full moon when the side of the moon facing the earth is illuminated by the sun. The side of the moon facing on point on the earth is very slightly different from that facing another point, so it's possible for the moon to be full as seen from one place but very slightly un-full from another, but the difference is so small as to be unnoticable in practice. -- Richard -- "Consideration shall be given to the need for as many as 32 characters in some alphabets" - X3.4, 1963.

	#3
Llanzlan Klazmon the 15th	Re: Question about the full moon "Hungerdunger" <Hungerdunger@celynnen.MARXdemon.co.uk> wrote in news:epbbcl$47m$1$8300dec7@news.demon.co.uk: > I know nothing about astronomy, but I have a dispute which someone here > might be able to settle for me: > > When it's a full moon in the UK, is it also a full moon in all other > parts of the world at around the same time, or does it vary according to > latitude ot longitude? > The moon is full everywhere at the same time for casual observation. There will be a small difference just because of the different position that viewers are looking from. I believe the official definition of full moon is when the moon's ecliptic longitude is exactly 180 degrees different to the Sun. Half of the Earth cannot see this exact event because it is daytime for that half ;-). As the Moon's orbit is inclined to the ecliptic you could argue that a 'true' full Moon is impossible, as when the Moon is exactly opposite the Sun in 3D it is in the Earth's shadow (lunar eclipse) and thus not illuminated except by stray light refracted/scattered by the Earth's atmosphere. Klazmon

	#4
Paul Clark	Re: Question about the full moon A think 'full moon' is a sort of non-scientific term. A more precise term is opposition. That is the instant that the moon is directly on the opposite side of the earth from the sun. Opposition is at the same time wherever you are located on the earth. Cheers Paul "Hungerdunger" <Hungerdunger@celynnen.MARXdemon.co.uk> wrote in message news:epbbcl$47m$1$8300dec7@news.demon.co.uk... >I know nothing about astronomy, but I have a dispute which someone here >might be able to settle for me: > > When it's a full moon in the UK, is it also a full moon in all other parts > of the world at around the same time, or does it vary according to > latitude ot longitude? > > -- > Hungerdunger > To reply by email, remove the MARX from my address >

	#5
Hungerdunger	Re: Question about the full moon "Paul Clark" <dr.clark@dial.pipex.com> wrote in message news:SqudncOtPoXEzyfYRVnyvgA@pipex.net... >A think 'full moon' is a sort of non-scientific term. > > A more precise term is opposition. That is the instant that the moon is > directly on the opposite side of the earth from the sun. Opposition is at > the same time wherever you are located on the earth. Thank you, everyone, for your replies. I thought I'd get a sensible answer here. -- Hungerdunger To reply by email, remove the MARX from my address

	#6
Weatherlawyer@gmail.com	Re: Question about the full moon > Paul"Hungerdunger" <Hungerdun...@celynnen.MARXdemon.co.uk> wrote in messagenews:epbbcl$47m$1$8300dec7@news.demon.co.uk ... > > >I know nothing about astronomy, but I have a dispute which someone > > here might be able to settle for me: > > > When it's a full moon in the UK, is it also a full moon in all other parts > > of the world at around the same time, or does it vary according to > > latitude or longitude? Ignorant and/or lazy poster: On Jan 26, 7:11 pm, "Paul Clark" <dr.cl...@dial.pipex.com> top posted: <corrected> > A think 'full moon' is a sort of non-scientific term. > > A more precise term is opposition. That is the instant that the moon is > directly on the opposite side of the earth from the sun. Opposition is at > the same time wherever you are located on the earth. It takes something like 30 hours for the percentage visibility to go from 99% through 100% (full) to 99% again. So the moon will appear full for almost everyone on the planet. It can seem to be full for two transits on occasion. A transit to transit is a "tidal day" of just over 24 hours and 50 or 55 minutes, IIRC. It takes something like 20 hours for the moon to go from 1% visibility through new moon to 1% again. (Or is that the times for half percentages I remember?)