| |
Main
Date: 02 Oct 2006 19:56:48
From: brucegooglegroups
Subject: moon atlas; questions about moon
|
Tonight I was viewing the moon. I had a difficult time matching my view
with moon charts in books and the one from S&T.
www.lunarrepublic.com/atlas/index.shtml is a good site, though.
I am using a 4.5 Newtonian reflector, with a Plossl 10x eyepiece and a
filter. I assume that my view is upside down and right is west.
In my view, on the lower side of the moon( North in my telescope?), I
could see one large crater, and six craters near it.
The surface was flat. I also saw two craters directly right on the
edge.
Was I looking at the Northern Mare Imbrium?
Thanks.
Bruce
|
|
| |
Date: 03 Oct 2006 08:49:53
From: brucegooglegroups
Subject: Re: moon atlas; questions about moon
|
Hi,
I just wanted a simple answer:)
I have a Dobsonsion skyquest 4.5 reflector. I am new to astronomy.
So- when viewing the moon, let's say the bottom- is it north and not
south?
BTW, what's an internet troll? I know that in Peer Gynt by Ibsen, Peer
was almost forced in marriage with cave troll as I recall:)
I suppose an internet troll doesn't stray far from that definition.
Thanks.
Bruce
Starlord wrote:
> Me smells a TROLL.
>
>
> --
> The Lone Sidewalk Astronomer of Rosamond
>
> Telescope Buyers FAQ
> http://home.inreach.com/starlord
> Sidewalk Astronomy
> www.sidewalkastronomy.info
> The Church of Eternity
> http://home.inreach.com/starlord/church/Eternity.html
>
>
> "rAgAv" <ragav.payne@googlemail.com> wrote in message
> news:1159872776.511040.175480@i42g2000cwa.googlegroups.com...
> >
> > Can you give me a piece of info.?
> >
> > How does the American flag look, through your telescope?
> >
> > --
> > Thanks in advance,
> > rAgAv
> >
|
| | |
Date: 03 Oct 2006 19:43:47
From: William Hamblen
Subject: Re: moon atlas; questions about moon
|
On 3 2006 08:49:53 -0700, "brucegooglegroups"
<brucegooglegroups@hotmail.com > wrote:
>I have a Dobsonsion skyquest 4.5 reflector. I am new to astronomy.
>So- when viewing the moon, let's say the bottom- is it north and not
>south?
The answer is "it depends." Assuming you are in the northern
hemisphere, the moon is due south and you are straddling your
telescope looking straight down into the eyepiece, the south side of
the moon would be straight up. In any other case the moon would
appear to be tilted. Just turn the moon map until it matches the view
through the eyepiece.
Bud
--
The night is just the shadow of the Earth.
|
| | |
Date: 03 Oct 2006 10:42:41
From: Starlord
Subject: Re: moon atlas; questions about moon
|
When viewing via a dob (or most scopes without the extra goodie that rights
the image) you are seeing SOUTH at the top and the image is also backwards,
I've got 3 dobs myself and when viewing DSO's it's no big deal.
--
The Lone Sidewalk Astronomer of Rosamond
Telescope Buyers FAQ
http://home.inreach.com/starlord
Sidewalk Astronomy
www.sidewalkastronomy.info
The Church of Eternity
http://home.inreach.com/starlord/church/Eternity.html
"brucegooglegroups" <brucegooglegroups@hotmail.com > wrote in message
news:1159890593.868123.288920@i42g2000cwa.googlegroups.com...
> Hi,
> I just wanted a simple answer:)
> I have a Dobsonsion skyquest 4.5 reflector. I am new to astronomy.
> So- when viewing the moon, let's say the bottom- is it north and not
> south?
>
> BTW, what's an internet troll? I know that in Peer Gynt by Ibsen, Peer
> was almost forced in marriage with cave troll as I recall:)
>
> I suppose an internet troll doesn't stray far from that definition.
> Thanks.
> Bruce
>
> Starlord wrote:
>> Me smells a TROLL.
>>
>>
>> --
>> The Lone Sidewalk Astronomer of Rosamond
>>
>> Telescope Buyers FAQ
>> http://home.inreach.com/starlord
>> Sidewalk Astronomy
>> www.sidewalkastronomy.info
>> The Church of Eternity
>> http://home.inreach.com/starlord/church/Eternity.html
>>
>>
>> "rAgAv" <ragav.payne@googlemail.com> wrote in message
>> news:1159872776.511040.175480@i42g2000cwa.googlegroups.com...
>> >
>> > Can you give me a piece of info.?
>> >
>> > How does the American flag look, through your telescope?
>> >
>> > --
>> > Thanks in advance,
>> > rAgAv
>> >
>
|
| | | |
Date: 03 Oct 2006 18:10:14
From: Chris L Peterson
Subject: Re: moon atlas; questions about moon
|
On Tue, 3 2006 10:42:41 -0700, "Starlord"
<starlord@sidewalkastronomy.info > wrote:
>When viewing via a dob (or most scopes without the extra goodie that rights
>the image) you are seeing SOUTH at the top and the image is also backwards,
>I've got 3 dobs myself and when viewing DSO's it's no big deal.
Most Dobs are Newts, and they don't produce a backwards image (just
upside down). And I think you're over-generalizing orientation. First of
all, you don't know the position of the eyepiece around the OTA, and
that affects orientation. Second, you don't know what the observer
considers the "top". Finally, a Dob has an altaz mount, and therefore
the field rotates. If you determine that south is at the "top", it won't
be a few hours later.
I think a more general explanation would simply be that it is unlikely
that the orientation seen through the eyepiece will match the
orientation seen with the naked eye. Combine that with some
magnification, and many beginning observers have some difficulty with
orientation.
_________________________________________________
Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com
|
| | | | |
Date: 03 Oct 2006 13:14:56
From: Starlord
Subject: Re: moon atlas; questions about moon
|
It's odd, that as long as I've had any Dob telescope (starting with a 12.5
f4.8 DSE in Hawaii ) the image has always been just the oppsit of what I see
with my eyes, insted of it being ) I see it as ( and from the map I used to
have and pictures in magazines, etc. and they have the south pole area
marked, that's what I see at the top of my EP image.
I guess all those maps and stuf are wrong?
--
The Lone Sidewalk Astronomer of Rosamond
Telescope Buyers FAQ
http://home.inreach.com/starlord
Sidewalk Astronomy
www.sidewalkastronomy.info
The Church of Eternity
http://home.inreach.com/starlord/church/Eternity.html
"Chris L Peterson" <clp@alumni.caltech.edu > wrote in message
news:mb95i2p8mdu2e3o2hingqr3hq41l8gkv8h@4ax.com...
> On Tue, 3 2006 10:42:41 -0700, "Starlord"
> <starlord@sidewalkastronomy.info> wrote:
>
>>When viewing via a dob (or most scopes without the extra goodie that
>>rights
>>the image) you are seeing SOUTH at the top and the image is also
>>backwards,
>>I've got 3 dobs myself and when viewing DSO's it's no big deal.
>
> Most Dobs are Newts, and they don't produce a backwards image (just
> upside down). And I think you're over-generalizing orientation. First of
> all, you don't know the position of the eyepiece around the OTA, and
> that affects orientation. Second, you don't know what the observer
> considers the "top". Finally, a Dob has an altaz mount, and therefore
> the field rotates. If you determine that south is at the "top", it won't
> be a few hours later.
>
> I think a more general explanation would simply be that it is unlikely
> that the orientation seen through the eyepiece will match the
> orientation seen with the naked eye. Combine that with some
> magnification, and many beginning observers have some difficulty with
> orientation.
>
> _________________________________________________
>
> Chris L Peterson
> Cloudbait Observatory
> http://www.cloudbait.com
|
| | | | | |
Date: 04 Oct 2006 00:58:11
From: Chris L Peterson
Subject: Re: moon atlas; questions about moon
|
On Tue, 3 2006 13:14:56 -0700, "Starlord"
<starlord@sidewalkastronomy.info > wrote:
>It's odd, that as long as I've had any Dob telescope (starting with a 12.5
>f4.8 DSE in Hawaii ) the image has always been just the oppsit of what I see
>with my eyes, insted of it being ) I see it as ( and from the map I used to
>have and pictures in magazines, etc. and they have the south pole area
>marked, that's what I see at the top of my EP image.
>
>I guess all those maps and stuf are wrong?
Maybe you are confusing backwards with upside down? If you look at a
street sign during the day is it actually backwards, as if viewed in a
mirror?
If your EP is on top, and you straddle the scope, I'd expect what you
see through the scope to appear upside down compared with what you see
with your naked eye.
_________________________________________________
Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com
|
| |
Date: 03 Oct 2006 05:43:23
From: brucegooglegroups
Subject: Re: moon atlas; questions about moon
|
brucegooglegroups wrote:
> Hi RAGAV,
> Is this a joke or an straight ahead question?
> My telescope is an Orion xt4.5.
> Bruce
> rAgAv wrote:
> > Can you give me a piece of info.?
> >
> > How does the American flag look, through your telescope?
> >
> > --
> > Thanks in advance,
> > rAgAv
I should have added- an Xt4.5 Dobsonian.
Bruce
|
| |
Date: 03 Oct 2006 05:40:07
From: brucegooglegroups
Subject: Re: moon atlas; questions about moon
|
Hi RAGAV,
Is this a joke or an straight ahead question?
My telescope is an Orion xt4.5.
Bruce
rAgAv wrote:
> Can you give me a piece of info.?
>
> How does the American flag look, through your telescope?
>
> --
> Thanks in advance,
> rAgAv
|
| | |
Date: 04 Oct 2006 00:14:31
From: Trane Francks
Subject: Re: moon atlas; questions about moon
|
On 2006-10-03 21:40 +0900, brucegooglegroups wrote:
> Hi RAGAV,
> Is this a joke or an straight ahead question?
> My telescope is an Orion xt4.5.
> Bruce
> rAgAv wrote:
>> Can you give me a piece of info.?
>>
>> How does the American flag look, through your telescope?
>>
>> --
>> Thanks in advance,
>> rAgAv
Don't sweat it, Bruce. It doesn't matter what telescope you have. There
are no telescopes (yet) that can resolve something as small as the flag
on the moon. Someday, perhaps, but not today.
trane
--
/////////////////////////////////////////////////////////
// Trane Francks trane@gol.com Tokyo, Japan
// Practice random kindness and senseless acts of beauty.
|
| |
Date: 03 Oct 2006 03:52:56
From: rAgAv
Subject: Re: moon atlas; questions about moon
|
Can you give me a piece of info.?
How does the American flag look, through your telescope?
--
Thanks in advance,
rAgAv
|
| | |
Date: 03 Oct 2006 07:30:57
From: Starlord
Subject: Re: moon atlas; questions about moon
|
Me smells a TROLL.
--
The Lone Sidewalk Astronomer of Rosamond
Telescope Buyers FAQ
http://home.inreach.com/starlord
Sidewalk Astronomy
www.sidewalkastronomy.info
The Church of Eternity
http://home.inreach.com/starlord/church/Eternity.html
"rAgAv" <ragav.payne@googlemail.com > wrote in message
news:1159872776.511040.175480@i42g2000cwa.googlegroups.com...
>
> Can you give me a piece of info.?
>
> How does the American flag look, through your telescope?
>
> --
> Thanks in advance,
> rAgAv
>
|
| |
Date: 03 Oct 2006 15:32:58
From: Willie R. Meghar
Subject: Re: moon atlas; questions about moon
|
"brucegooglegroups" wrote:
>Tonight I was viewing the moon. I had a difficult time matching my view
>with moon charts in books and the one from S&T.
>www.lunarrepublic.com/atlas/index.shtml is a good site, though.
>
>I am using a 4.5 Newtonian reflector, with a Plossl 10x eyepiece and a
>filter. I assume that my view is upside down and right is west.
If you compare the low-powered telescopic view with the naked eye view
(paying particular attention to the phase and major mare regions) it
should be possible to determine how the view in your telescope is
oriented in relation to the naked eye view.
Typically, a Newtonian telescope provides an upside down, correct (not
mirror-reversed) image; but the exact rotation of the image will vary
with where your eyepiece is and where the moon is in the sky. In
other words, unless you're using a mirror-reversed moon map, it should
be possible to rotate the map until it matches the image orientation
seen in your eyepiece. (Those using non-Newtonian telescopes (with
minor exceptions) equipped with a star diagonal would be better off
with a mirror-reversed moon map.)
When looking at the moon through a telescope, if you nudge the front
end of the scope upward (northward) the moon's southern hemisphere
will move toward the edge of your field of view.
East and West on the moon can be somewhat more confusing, especially
since those directions got reversed around the time of the Apollo
program. This means that West on the old moon maps is the same as
East on today's moon maps! (Some of us are old enough to remember
this change;-) It might help to remember that during the first
quarter phase the moon's eastern hemisphere is illuminated.
The reason for the reversal of east and west was so that astronauts
would see the sun rise in the east and set in the west -- provided any
astronauts ever spend sufficient lengths of time on the moon.
As a result of the confusing directions, I usually prefer to use the
terms 'preceding' and 'following' instead of 'east' and 'west' ;-)
If you're not confused yet, I'll just add: The moon's eastern
hemisphere is on the western (using 'sky directions') side of the
moon!
>In my view, on the lower side of the moon( North in my telescope?), I
>could see one large crater, and six craters near it.
>The surface was flat. I also saw two craters directly right on the
>edge.
>
>Was I looking at the Northern Mare Imbrium?
It's tough to say. My best guess would be that you've mistaken Mare
Serenitatis for Mare Imbrium; but that's just a guess based largely on
the moon's phase at the time of observation.
Willie R. Meghar
Observational Notes at:
http://meghar.blogspot.com/
|
| |
Date: 03 Oct 2006 11:56:09
From: canopus56
Subject: Re: moon atlas; questions about moon
|
brucegooglegroups wrote:
> Tonight I was viewing the moon. I had a difficult time matching my view
> with moon charts in books . . . and the one from S&T.
> www.lunarrepublic.com/atlas/index.shtml is a good site, though.
> . . . [O]n the lower side of the moon( North in my telescope?), I
> could see one large crater, and six craters near it.
> The surface was flat. I also saw two craters directly right on the
> edge. Was I looking at the Northern Mare Imbrium?
Your description sounds like you were looking at the crater Plato on
the north edge of Mare Imbrium. The other large prominent crater
visible at that time was Copernicus, but its floor is not a flat plain.
The six craters reference does not ring any bells.
At the time of your post, the lunar terminator was at approx. 40W with
a lunar age of 10.7 days. Henrik Bondo's original edition evening lunar
atlas at:
http://inet.uni2.dk/~d120588/henrik/ela0_sessions.html
contains photos of the Moon by lunar age. That may help you to get
oriented. Bondo's 10.9 lunar day image is at:
http://inet.uni2.dk/~d120588/henrik/ela1_387w_109d_19apr05.html
Using your own lunar hardcopy map or the "lunar republic" map, you can
match up the craters in Bondo's image with their names. The "lunar
republic" image for Plato is B-3:
http://www.lunarrepublic.com/atlas/sections/b3.shtml
Copernicus is on "lunar republic" image D-2 and D-3.
When you begin to watch the Moon, it is typical to have problems
matching the chart to the image do to changes in the apparent view of
its surface. Those changes include:
1) phase change - where the terminator is. See -
http://www.lpod.org/archive/LPOD-2005-02-21.htm
2) parallactic angle - the angle of the Moon's north-south pole and
your local meridian.
3) libration - the Moon's orbit is inclined at 6 degrees to the
ecliptic. Sometimes you are looking "down" on the Moon; at others you
look "up" from below at the Moon. Libration effects range from about 7
degrees of selenographic latitude and up to 10 degrees in selenographic
longitude.
To understand libration, it helps to have a friend stand in front of
you. Look at their face at various angles, including by stooping and
looking up from below, or standing on ladder or stair case and looking
down from above.
A good illustration of this can be found on page 10 of Chong, S.M. et
al. 2002. A Photographic Altas of the Moon. Cambridge Univ. Press. ISBN
0-521-81392-1.
Chong's book is available on Amazon.com.
http://www.amazon.ca/exec/obidos/ASIN/0521813921
Excerpts from Chong's book, including the illustration of libration on
page 10, can be seen online using Amazon's "Search this book" feature.
The process I went through when first learning the Moon was:
1) Learn the major mare phase asterisms using the Astronomical
League's Lunar Observing List:
http://www.astroleague.org/al/obsclubs/lunar/lunar3.html
2) Using a whole Moon chart, like the ARVAL Moon Map, learn the major
fiducial craters that catch the eye on any casual inspection of the
Moon.
http://www.oarval.org/MoonMapen.htm
Some of the major fiducial craters include Atlas, Hercules, Mostling A
(a small crater near selenographic 0 degs lat, 0 deg long),
Ptolemaeus-Alphonsus, Clavius, Tycho, Plato, Kepler, Eratosthenes,
Copernicus, Archimedes, Gassendi, Aristarchus, and Grimaldi.
Then learn the fiducial mountain ranges like: Montes Caucasus, Montes
Alpes, Montes Jura, Montes Apenninus and Montes Pyrenaeus.
3) Using a lunar planetarium program like the freeware Virtual Moon
Atlas,
http://www.astrosurf.com/avl/UK_index.html
follow the Moon each night for one entire lunation. Pay particular
attention to
(a) the lunar longitude of the terminator each night. The Hitchhiker's
Guide to the Moon has a convenient online calculator to tell you the
lunar longitude of the terminator for a particular night.
http://www.shallowsky.com/moon/hitchhiker.html
Virtual Moon Atlas also reports this colongitude of the terminator, and
has tools that identify the major cool things to look at along the
terminator.
(b) the eclipitic latitude of the Moon - that partially defines the
libration viewing angle,
(c) how the phase is related to the position of the Moon in its orbit
around the Earth and the rising time of the Moon - first quarter Moon
sets after sunset in the West, third quarter rises in the east in the
early morning hours.
You can even do this online using the USNO "What the Moon looks like"
today.
http://aa.usno.navy.mil/data/docs/current_moon.html
4) Read Dr. Chuck Wood's Lunar Picture of the Day (LPOD) daily and his
monthly S&T column for in depth notes on particular objects.
www.lpod.org
A couple of lunations (monthly lunar cycles) of this and you'll be an
old hand!
When first learning the feature names, it is also helpful (for learning
purposes) to adopt the mindset of 17th and 18th century astronomers how
first named the Moon's features. They viewed the Moon like the Earth -
it had highland continents (terra), oceans (oceanus), seas (mare),
lakes (lacus) and marshes (palus). Headlands (promintorium) stick out
into the "oceans" and "seas". Although we no longer use the former
names of the continents, -
http://www.lpod.org/?m=20060418
- it is helpful to understand the early astronomers' mindset when they
were naming features.
Hope this helps.
Clear skies - Canopus56
|
|
