Navigator wrote:
What location has moon rise and set 12 hours apart?

Virtually anywhere, I'd guess - just had a look at moon rise and set for
some random locations (Glasgow, Jerusalem and Canberra), for today, and
they're all a shade over 12 hours apart. If rise/set are close to due
east/west, then the time for the moon to traverse the sky will be about 12
hours - think about the solar equinoxes, where the sun rises/sets due
east/west. I dare say this princple won't hold at extreme latitudes. The
moon passes the due east/west points twice in its mo(o)nthly cycle.


--
Wally
www.forthsailing.com
www.wally.myby.co.uk

Wally wrote:
Navigator wrote:

What location has moon rise and set 12 hours apart?


Virtually anywhere, I'd guess - just had a look at moon rise and set for
some random locations (Glasgow, Jerusalem and Canberra), for today, and
they're all a shade over 12 hours apart. If rise/set are close to due
east/west, then the time for the moon to traverse the sky will be about 12
hours - think about the solar equinoxes, where the sun rises/sets due
east/west. I dare say this princple won't hold at extreme latitudes. The
moon passes the due east/west points twice in its mo(o)nthly cycle.


The devil _is_ in the detail and is it ever 12 hours????

Cheers

Navigator wrote:

The devil _is_ in the detail and is it ever 12 hours????

What part of 'find lunar noon' are you ignoring in lieu of trolling for
nanosecond-precise astronomical timing?


--
Wally
www.forthsailing.com
www.wally.myby.co.uk

"Navigator" wrote in message
...


Wally wrote:
Navigator wrote:

What location has moon rise and set 12 hours apart?


Virtually anywhere, I'd guess - just had a look at moon rise and set for
some random locations (Glasgow, Jerusalem and Canberra), for today, and
they're all a shade over 12 hours apart. If rise/set are close to due
east/west, then the time for the moon to traverse the sky will be about 12
hours - think about the solar equinoxes, where the sun rises/sets due
east/west. I dare say this princple won't hold at extreme latitudes. The
moon passes the due east/west points twice in its mo(o)nthly cycle.


The devil _is_ in the detail and is it ever 12 hours????


Why not? What's the problem? Or are you making the sophomoric argument that
its very unlikely to be "precisely" 12 hours? It certainly isn't hard to find
places and times where its within a couple of minutes. Certain latitudes are
more favorable than others for this situation to exist, but there's nothing the
precludes it.

Have a go with:
http://aa.usno.navy.mil/ select "Data Services" and then "Table of
sunrise/sunset ..."

No, I'm trying to get people to think about the relationship between
altitude and period between rise and set for a fixed lunar orbital period.

Cheers

Jeff Morris wrote:

"Navigator" wrote in message
...


Wally wrote:

Navigator wrote:


What location has moon rise and set 12 hours apart?


Virtually anywhere, I'd guess - just had a look at moon rise and set for
some random locations (Glasgow, Jerusalem and Canberra), for today, and
they're all a shade over 12 hours apart. If rise/set are close to due
east/west, then the time for the moon to traverse the sky will be about 12
hours - think about the solar equinoxes, where the sun rises/sets due
east/west. I dare say this princple won't hold at extreme latitudes. The
moon passes the due east/west points twice in its mo(o)nthly cycle.



The devil _is_ in the detail and is it ever 12 hours????



Why not? What's the problem? Or are you making the sophomoric argument that
its very unlikely to be "precisely" 12 hours? It certainly isn't hard to find
places and times where its within a couple of minutes. Certain latitudes are
more favorable than others for this situation to exist, but there's nothing the
precludes it.

Have a go with:
http://aa.usno.navy.mil/ select "Data Services" and then "Table of
sunrise/sunset ..."

Sounds more like you don't know what you're talking about.



"Navigator" wrote in message
...
No, I'm trying to get people to think about the relationship between
altitude and period between rise and set for a fixed lunar orbital period.

Cheers

Jeff Morris wrote:

"Navigator" wrote in message
...


Wally wrote:

Navigator wrote:


What location has moon rise and set 12 hours apart?


Virtually anywhere, I'd guess - just had a look at moon rise and set for
some random locations (Glasgow, Jerusalem and Canberra), for today, and
they're all a shade over 12 hours apart. If rise/set are close to due
east/west, then the time for the moon to traverse the sky will be about 12
hours - think about the solar equinoxes, where the sun rises/sets due
east/west. I dare say this princple won't hold at extreme latitudes. The
moon passes the due east/west points twice in its mo(o)nthly cycle.



The devil _is_ in the detail and is it ever 12 hours????



Why not? What's the problem? Or are you making the sophomoric argument
that
its very unlikely to be "precisely" 12 hours? It certainly isn't hard to
find
places and times where its within a couple of minutes. Certain latitudes
are
more favorable than others for this situation to exist, but there's nothing
the
precludes it.

Have a go with:
http://aa.usno.navy.mil/ select "Data Services" and then "Table of
sunrise/sunset ..."

Are you saying that the peiod between rise and set is fixed?

Cheers

Jeff Morris wrote:

Sounds more like you don't know what you're talking about.



"Navigator" wrote in message
...

No, I'm trying to get people to think about the relationship between
altitude and period between rise and set for a fixed lunar orbital period.

Cheers

Jeff Morris wrote:


"Navigator" wrote in message
...


Wally wrote:


Navigator wrote:



What location has moon rise and set 12 hours apart?


Virtually anywhere, I'd guess - just had a look at moon rise and set for
some random locations (Glasgow, Jerusalem and Canberra), for today, and
they're all a shade over 12 hours apart. If rise/set are close to due
east/west, then the time for the moon to traverse the sky will be about 12
hours - think about the solar equinoxes, where the sun rises/sets due
east/west. I dare say this princple won't hold at extreme latitudes. The
moon passes the due east/west points twice in its mo(o)nthly cycle.



The devil _is_ in the detail and is it ever 12 hours????



Why not? What's the problem? Or are you making the sophomoric argument

that

its very unlikely to be "precisely" 12 hours? It certainly isn't hard to

find

places and times where its within a couple of minutes. Certain latitudes

are

more favorable than others for this situation to exist, but there's nothing

the

precludes it.

Have a go with:
http://aa.usno.navy.mil/ select "Data Services" and then "Table of
sunrise/sunset ..."

Are you claiming its broken?

There are a number of factors that determine the time between moonrise and
moonset. However, there is no reason why a 12 hour duration can't occur, and no
reason why it can't happen from 4pm to 4am.

Now you can claim that you were "trying to get people thinking about something"
but I claim you have no idea about lunar noon and it relationship to the tides,
and that you had some bizarre notion that a 12 hour duration was not possible.


"Navigator" wrote in message
...
Are you saying that the peiod between rise and set is fixed?

Cheers

Jeff Morris wrote:

Sounds more like you don't know what you're talking about.



"Navigator" wrote in message
...

No, I'm trying to get people to think about the relationship between
altitude and period between rise and set for a fixed lunar orbital period.

Cheers

Jeff Morris wrote:


"Navigator" wrote in message
...


Wally wrote:


Navigator wrote:



What location has moon rise and set 12 hours apart?


Virtually anywhere, I'd guess - just had a look at moon rise and set for
some random locations (Glasgow, Jerusalem and Canberra), for today, and
they're all a shade over 12 hours apart. If rise/set are close to due
east/west, then the time for the moon to traverse the sky will be about
12
hours - think about the solar equinoxes, where the sun rises/sets due
east/west. I dare say this princple won't hold at extreme latitudes. The
moon passes the due east/west points twice in its mo(o)nthly cycle.



The devil _is_ in the detail and is it ever 12 hours????



Why not? What's the problem? Or are you making the sophomoric argument

that

its very unlikely to be "precisely" 12 hours? It certainly isn't hard to

find

places and times where its within a couple of minutes. Certain latitudes

are

more favorable than others for this situation to exist, but there's nothing

the

precludes it.

Have a go with:
http://aa.usno.navy.mil/ select "Data Services" and then "Table of
sunrise/sunset ..."

Navigator wrote:

No, I'm trying to get people to think about the relationship between
altitude and period between rise and set for a fixed lunar orbital
period.

Not so much a side-step, as a stumble.


--
Wally
www.forthsailing.com
www.wally.myby.co.uk

C'mon you can try better than that.

Cheers

Wally wrote:

Navigator wrote:


No, I'm trying to get people to think about the relationship between
altitude and period between rise and set for a fixed lunar orbital
period.


Not so much a side-step, as a stumble.