CALCLUN©

Virtual Moon Atlas Ephemeris Calculator
Documentation usable for the version 8
Welcome to "CALCLUN" the ephemeris calculation module
integrated in the "Virtual Moon Atlas".
As amateur astronomers ourselves, we continue to refine the AVL to design
software that is ever more useful for lunar observers and practical for use in thefield.
We always try to define the most user-friendly and intuitive features and interface
possible.
This is why we have incorporated a lunar ephemeris calculator designed andprogrammed by Patrick Chevalley called "CALCLUN" (c) which allows you toprepare your lunar observation or imaging sessions in detail.
.
This first version includes the functions that we found most useful. We are thinking
about other possibilities that will eventually be included in the following versions.
We advise you to read this manual carefully, practicing at the same time thehandling of the functions described in order to discover all the functions of themodule.
Have a good use and we hope you enjoy this new program and recommend it
around you.
Thank you very much for your trust.
Christian Legrand & Patrick Chevalley

THE CALCLUN MODULE :CALCLUN © is a module of the Virtual Moon Atlas calculating lunar ephemerides
over durations ranging from a day to a year.
It can be called from the “Command Center” screen by clicking on the CALCLUN
button or from the same button in the button bar of the ATLUN module. It is also
possible to launch it from the "Right click" contextual menu of the ATLUN module.

Finally, it can be launched from the calclun.exe file present in the VirtualMoon
directory.
It was designed in the same spirit as DATLUN©, the Virtual Moon Atlas lunar
formation database management software also designed and programmed byPatrick Chevalley.

THE CALCLUN SCREEN

The CALCLUN screen fits in a "Windows" window. Like all Windows windows, youcan minimize, maximize or adapt its size by clicking on the buttons to the right of thetitle bar. From the CCLun Command Center, it is possible to simultaneously open
the other VMA modules (DATLUN / PHOTLUN / WEBLUN / NOTELUN ) and
CALCLUN, which allows the study of the Moon, while having access to the others
VMA functions.
The CALCLUN window includes:- The menu bar- The date selection banner- The Ephemeris duration selection tabs
- The graph window on the right if there is one associated.

THE MENU BAR
In CALCLUN, this bar presents only one menu.

THE "Setup" MENU
It is used in CALCLUN to access settings for location, time zone and language. It
has only one "Configuration" tab.

"Setup" TAB
Observatory coordinates
The software takes into account the coordinates and altitude of the observationsite to display the lunar globe in real time and in 3D, taking into account the socalled "diurnal" libration.
"Date / Hour" FrameThe "Date / Time" frame allows you to specify the country and the time zoneto use. CEST stands for "Central European Summer Time". This is indicatedfrom the date internal to your computer if the territory is in daylight saving time.

"Languages" drop-down list
The "Language" drop-down list allows you to choose the language used by thesoftware and the database. In the distributed version, you have French and English.
Are now also available in alphabetical order:- German- Catalan- Croatian- Spanish- Greek- Dutch- Hungarian- Italian- Lithuanian- SlovakYou can then download from the VMA site the translations of the words andexpressions used in the menus for the languages not included in the distributionversion. The translations page of the VMA site also indicates if translations of thedatabase are available in this new language.
You can also offer yourself as a translator in a language not yet supported.
We would particularly like to thank the authors of the already existing translations
for their support for our action.
Click on the "OK" button once your settings have been made or on the "Cancel"
button to disregard them.

THE DATE SELECTION BANNER

The top banner allows you to choose a start date for the ephemeris calculation. Youcan change the year and/or the month and/or the day and validate the changes bypressing the "Enter" key. CEST stands for "Central European Summer Time".
This is indicated from the date internal to your computer if the territory is in daylightsaving time.
You can instantly return to today's date by clicking the "Today" button.
Finally, you can jump to the previous month or the next month by clicking on the "<"or ">" buttons.

EPHEMERIDES DURATION SELECTION TABS
"Year" TAB

By clicking on this tab, the display will show:- At the top left an annual graphic calendar of the lunar phases- Bottom left: A table of the ephemerides of the phases of the Moon and theextrema of the librations for the year.
- On the right: A graphic representation of the visibility of the Moon throughout theyear, differentiating between day and night.

"Month" TAB

By clicking on this tab, the display will show:- On the left: the lunar ephemerides of the selected month. Are displayed in column
the numerical values over the duration of the month of :- Right ascension in coordinates 2000
- Declination in 2000 coordinates- Apparent right ascension- Apparent variation- Distance in km- Diameter in minutes of arc- Phase as the terminator value over 360° of longitude.
- Number of days of the Lunar Season- Illumination of the Visible Face from 0 to 100%
- Colongitude as the lunar morning terminator value over 360° longitude- Sub-solar latitude (Latitude of the place on the lunar surface where the Sun isat its zenith).
- Liberation in longitude- Liberation in latitude- PA is for "Position Angle", the angle between North Celestial Pole (NCP) andthe Moon.
- Sunrise time
- Bedtime- Top right: A frame with the dates and times of the Quarters, New Moon and Full
Moon of the month.

- A "Chart selection" button which gives access to the drop-down list of chart types
that will bedisplayed under the button.
- Right ascension in coordinates 2000
- Declination in 2000 coordinates- Apparent right ascension- Apparent variation- Distance in km- Diameter in minutes of arc- Phase in the form of the graph of the value of the terminator over 360° oflongitude- Number of days of the Lunar Season- Illumination of the Visible Face from 0 to 100%
- Colongitude in the form of the graph of the value of the lunar morningterminator on 360° oflongitude- Sub-solar latitude (Latitude of the place on the lunar surface where the Sun isat its zenith)- Libration in longitude showing a graph of the libration in longitude and a graphof the global libration- Libration in latitude showing a graph of the libration in latitude and a graph of
the global libration- PA is for "Position Angle", the angle between North Celestial Pole (NCP) andthe Moon.
- Sunrise time showing a graph of the sunrise time and a diagram of thevisibility during the month- Set time showing a set time graph and visibility diagram during the month- One or two frames displaying the graphs selected in the drop-down list showing
the variation of the parameter(s) chosen with the values of the grids inserted in theordinate and abscissa.

"Day" TAB

By clicking on this tab, the display will show:- On the left: the lunar ephemerides of the day selected hour by hour. Are displayedin column the numerical values on the length of the day of:- Right ascension in coordinates 2000
- Declination in 2000 coordinates- Apparent right ascension- Apparent variation- Distance in km- Diameter in minutes of arc- Phase in the form of the graph of the value of the terminator over 360° oflongitude.
- Number of days since the beginning of the Lunation- Illumination of the Visible Face from 0 to 100%
- Colongitude as the longitude of the lunar morning terminator over 360° oflongitude- Sub-solar latitude (Latitude of the place on the lunar surface where the Sun isat its zenith).
- Liberation in longitude- Liberation in latitude- PA is for "Position Angle", the angle between the Celestial North Pole and theMoon.
- At the top right, a frame with the moonrise and moonset times for the chosen day,as well as a graphic representation of the phase- Below a frame showing the elevation of the Moon above the horizon according tothe hours.
- Three drop-down lists to choose a specific time to the nearest second- A frame presenting the values of the following parameters for the precise time
specified:- Right ascension in coordinates 2000
- Declination in 2000 coordinates- Apparent right ascension- Apparent variation- Distance in km- Diameter in minutes of arc- Colongitude as the lunar morning terminator value over 360° longitude- Sub-solar latitude (Latitude of the place on the lunar surface where the Sun isat its zenith).
- Liberation in longitude- Liberation in latitude- PA is for "Position Angle", the angle between the Celestial North Pole and theMoon.
- 360° azimuth with North at 0°- Elevation in degrees, positive above the horizon and negative below

"Prediction" TAB
By clicking on this tab, the display will show three tabs allowing forecasts oncolongitude (Longitude of the morning lunar terminator), on the elevation of the Sun
above a given formation or on the global lunar libration.
"Colongitude" TAB

This sub-tab includes:- Top left: a frame for entering the desired colongitude with its width of theterminator taken into account.
- Top center: a frame for entering the forecast time interval.
- Top right: a box for entering the observation constraints that you wish to take into
account (Night observation and selection of the observation time after sunset,
visibility of the Moon from the place of observation, height minimum of the Moon
above the horizon if there are obstacles.
- At the bottom: the results table of the forecast calculation"Sun elevation on a formation" TAB

This sub-tab includes:- At the top on the far left: a search framework for the desired formation. Enter thename in the box and click on the "Search" button. Then click on the formation thatinterests you in the drop-down list that appears.
- Top left: a box for entering the coordinates of the formation if it is not in one of thedatabases.
- Top center: a frame for entering the Sun's elevation limit constraints.
- Top right: a frame for entering the forecast duration targeted by the calculation.
- At the top on the far right: a frame for entering the observation constraints that you
wish to take into account (Night observation and selection of the observation timeafter sunset, visibility of the Moon from the place of observation, minimum heightof the Moon above the horizon if there are obstacles.
- Bottom: two tables of forecast calculation results for increasing solar elevation(Morning Terminator) and for decreasing solar elevation (Evening Terminator).
"Libration" TAB

This sub-tab includes:- At the top on the far left: a search framework for the desired training. Enter thename in the box and click on the "Search" button. Then click on the training thatinterests you in the drop-down list that appears.
- Top left: a box for entering the coordinates of the training if it is not in one of thedatabases.
- Top center: a frame for entering the desired libration stresses.
- Top right: a frame for entering the forecast duration targeted by the calculation.
- At the top on the far right: a frame for entering the observation constraints that you
wish to take into account (Night observation and selection of the observation timeafter sunset, visibility of the Moon from the place of observation, minimum heightof the Moon above the horizon if there are obstacles.
- At the bottom: the results table of the prediction calculation

COPYRIGHTSCALCLUN © was designed and programmed by Patrick Chevalley.
CALCLUN © is a trademark of Christian Legrand.
Any use of CALCLUN outside the Virtual Moon Atlas is subject to the priorauthorization of the authors.

"CALCLUN" MANUAL END
Copyright Christian Legrand & Patrick Chevalley / 2023
The authors kindly ask users to report any errors found in this manual to themthrough the forum on the website.