*0
MOON  FORECASTER  PERMANENT  SCREEN

      Data displayed are current date and time UTC, Moon Elevation (El), Azimuth (Az) and Doppler amount (D) at "Home" Station, as well as mutual Doppler (mD) between the "Home" and "DX" Station. Information about current "Home" and "DX" Stations are displayed on the uppermost line of the screen.

      As long as Moon Forecaster is "on", this screen remains on display. It can also be moved anywhere on the PC Screen.

MOON  FORECASTER  HELP  SCREEN

      When Help is set to YES, a Help Screen is available wherever the mouse pointer shows a question mark. To display the relevant Help Screen, click on the right button. To close the Help screen, click either on the upper right cross of the screen, or click anywhere outside of the screen with the left button.

      To disable the Help screen, click either on the left margin of the screen or on the sub menu "Help NO" of the menu "Help".

      The Help Screen can be moved across the PC Screen with the mouse if necessary. Its sizes can also been changed. Character size is then changed accordingly.

*1
MOON  OVERVIEW  GRAPH

      This is the plot of Declination (yellow curve) and Distance (cyan curve) vs Time. The Time Unit is the Month (format "yyyy Mmm"). Example: "August 2004" is written "2004 Aug".

      The numbered blue tags along the -30° declination line of the plot symbolise Week-Ends with their respective rank numbers along the year (see below).

      Quick Graph reading:

      Move the mouse across the plot. A yellow marking bar then moves left or right. Bar position shows Declination, Greenwich Hour Angle, Distance and Radial Speed, on the line just above the Graph. Date and Time UTC are shown on the line below the Graph. The yellow bar disappears when the mouse leaves the Graph window. The Date display includes the Week number. The Week # is computed according to the "Thursday's Rule": the Week #1 of the Year is the one that contains the first Thursday of the Year.

      Only Declination and Distance are plotted, because they are the most significant parameters for the choice of the "Best Possible Operating Window".

      For Northern Hemisphere, best condition grade is obtained when Moon is around highest northern Declination and around Perigee (closest point to the Earth). A given period can be qualified as best when Declination curve and Distance curve are "out of phase". This will prevail around the years 2007 to 2009. It was the case for the period 1999 to 2001. The period is about 8.5 years. Such conditions provide long duration of Moon availability, together with best theoretical signal strength.

      However, keep in mind that in practice, signal strength may be much more affected by atmospheric fluctuations and disturbances rather than by purely geometrical variations. 

      Graph functions:

      When the left button is clicked, the date displayed on the graph is transfered into the Date Screen, and the MUTUAL MOON WINDOW for this date is computed. All its related parameters are displayed accordingly. A fixed white bar replaces the yellow bar. This white bar position is updated everytime a new Moon Window is computed.

      Below the graph, a Slide Bar can be activated. Put the mouse on the cursor, keep the left button depressed, and move the mouse left or right. Every movement is followed by a complete computing update and a new display refresh, all relative to the new cursor position. If focus is kept on the Slide Bar, fine time adjustment can be obtained using the "left" or "right" arrow key on the key-board. Coarse adjusment can be also reached using the "page-up" or "page-down" key. Keeping one of these keys activated triggers animation: it is then possible to have a look at the Moon Figure changes at highly accelerated rate, giving an idea of the swinging and rocking motion of the Moon across the sky.

      No MUTUAL MOON WINDOW is computed with the Slide Bar.

      The lowermost part of the screen shows a set of buttons allowing various changes in the data displayed by the graph.

      Under "cold start" conditions, the default setting is a two month period, starting on the first day of the month date, and stopping on the last day of the next month. Example: Date is March 27th, 2002; selected "cold start" period is then March 1st, 2002 until April 30th, 2002.

      Month setting.

      Start Month: the Month for which computing of the plot starts.

      Use the small scroll-down menu or the buttons "<<" and ">>" to select a Start Month.

      Everytime the "<<" button is activated, the Previous Month to the Current Month shown between the button is selected.

      Everytime the ">>" button is activated the Next Month to the Current Month is selected.

      Stop Month: the Month for which computing stops. This month is selected the same way as the Start Month.

      Note:
      If the Stop Month is "earlier" than the Start Month, the Year of the "early" months is automatically incremented. Example: Start Month, Aug 2004; Stop Month, January 2004 ?? The Stop Month will be automatically incremented to January 2005. The Year will be correctly displayed on the Moon Motion Graph.

      Month settings remain the same, whichever the Year selected (see above). 
    
      Year setting.

      Any Year between 1945 and 2050 can be selected. However, Start Month and Stop Month will remain the same as previously set, either during "cold start" conditions, or manually (see above).

      The Year can be selected the same way as the Months, using either the scroll-down menu or both "<<" and ">>" buttons (see above).

      When the "Full Year" button is activated, the Moon Motion is plotted all over the Current Year, from January 1st until December 31st.

      "To-Day" function.

      When the "To-Day" button is activated, the computer resets all computings at the current Date and Time UTC, whichever the previous position is. If Real Time mode was activated, it is reset to Simulated Time mode. However, the Motion Graph is not modified if "To-Day" falls inside the Graph; the white Bar and the Slide are just reset at proper position.

	"Current Plot" function.

      When the "Current Plot" button is activated, the computer displays back the current month and the month after, inside the current year. This function is usefull when some explorations were carried on in the past or in the future. 

      WARNING !

      Real Time mode and To-Day function are consistent ONLY if the software is run in UTC. See "Set Local Time" and/or "Set UTC" menu help screens for UTC settings. ("Universal Time Coordinated", official definition since January 1978, is still better known as GMT, or "Greenwich Mean Time", although this last denomination should no be used any longer. The military "Z" or "Zulu" for UTC is also popular among hams).

*2
MUTUAL  MOON  WINDOW  SCREEN

      The yellow tape refers to the "Home" Station Window, the cyan tape, to the "DX" one. The Home Station Window is always centered on the plot. The DX Station Window is shown either on the left side of the local one when earlier, or on the right side when later. The span is ± 18 hours, centered on the Home Station Window.

      The cross-over part of the tapes is the so-called MUTUAL MOON WINDOW common to both Stations. The lower part of the screen shows the Mutual Window parameters, as follows:

      1) Time of Beginning (UTC),
      2) Duration, in hours, minutes and seconds (hh:mm:ss).
      3) Time of End (UTC), 

      If there is no mutual window, the warning message "No Mutual Window available !" is displayed.    

      Quick Graph reading:

      Move the mouse across the plot. A marking bar then moves left and right. Bar position shows Date and Time UTC (See Date display).

      Graph functions:

      When the left button is clicked, all Moon Parameters are updated and displayed accordingly.

      Below the graph, a Slide Bar can be activated. Put the mouse on the cursor and move left or right. Every movement is followed by complete update and new display refresh, all relative to the new cursor position. If focus is kept on the Slide Bar, fine time adjustment can be obtained using the "left" or "right" arrow key on the key-board. Coarse adjusment can also be reached using the "page-up" or "page-down" key. Lower speed animation can also be obtained if one of those keys is kept activated.

*3
MOON  DATA  AND  MOON  FIGURE  SCREEN

      This screen displays in bigger characters Moon Elevation and Azimuth at Date and Time UTC shown in the Date display above. It also shows in smaller characters Sun Elevation and Sun Azimuth at the same time. The screen also simulates the Moon figure as it appears to the operator/observer on the ground, as well as the background sky (daylight, twilight or dark). It also simulates Moon ashlight whenever it can be observed.

      When the Moon is below the horizon, a warning message reading "Moon below Horizon !" is displayed across the screen.

      Below the Moon figure, the actual Distance between the Station and the Moon is displayed, as well as the actual Radial Speed, i.e. the speed of the Moon along the Station to Moon axis, the motion of the Station around the Earth axis being taken into account. The Distance is given in kilometers (km), and the Radial Speed, in meters per second (m/s). The value of this "Station" Radial Speed is used to compute the Doppler shift as observed by the Station (see Moon advanced Parameters Window).

      Moon Rise (R), Transit (T) and Set (S) dates and times, as well as Azimuth (A) at Rise and Set, and Elevation (E) at Transit, are displayed in the following text windows. Rise and Set are computed under the following conditions: 1) Optical refraction is not taken into account.
2) Local Geometric Horizon is supposed to be "free of access" for any given Station.
      Clicking with the left button on any of the "Rise", "Transit" or "Set" text windows of either station refreshes all parameters and displays as of date and time shown in the text windows. If Timing is set in Real Time mode, it is reset to Simulated Time mode.

      The screen also shows Station's call-sign (yellow background for "Home" and cyan background for "DX"), and Station's coordinates (Latitude, Longitude and Grid Square).

      The "Home" or "DX" Station Call-Sign (or Radio Telescope) List is opened by "single-clicking" inside the related Screen with the left button. The Radio Telescope list is called upon "double-click". Alternate access is also possible using the "Select Home or DX" menu. There is a short-cut possibility to access the Station List, as follows:
      <Ctrl Q> for "Home" station,
      <Ctrl A> for "DX" station,
      <Ctrl W> for "Home" radio-telescope,
      <Ctrl S> for "DX" radio-telescope.

      This Radio Telescope list is also provided, because some of them have been activated by radio-amateurs in the past (Arecibo in 1965, Nançay in 1989, for example), and others may be activated in the future.

      Greenwich and Paris observatories, which are not radio telescopes, are included for the purpose of comparison with ephemeris data related to those observatories. For example, at Paris on 1978 July 2, the Moon transit took place at 09:34:24 UTC according to the French ephemeris "Connaissance des Temps". The software gives the same time.

      See specific STATION LIST SCREEN clause for further details. To access this help screen, first open the list as explained above, and then click inside the list with right button.

*4
MOON  PARAMETERS  SCREEN

	The upper-most part of the screen displays the Week #, and the UTC date and time.

      The upper part of the screen displays the standard Moon parameters usually available in major ephemeris publications and handbooks, like the "Nautical Almanac" or Russian "Astronomicheskyi Yezhegodnik" for example. These parameters are:

      1) The Declination (degrees),
      2) The Greenwich Hour Angle (degrees),
      3) The Earth to Moon Distance (center to center, km),
      4) The Radial Speed (Moon center to Earth center, m/s),
      5) The Phase Angle (degrees),
      6) The Moon to Sun Angle (degrees).
      

      The Declination is the angle made by the direction of the Moon refered to the Equator plane, the Earth center being the origin. It is counted from 0 up to +90° in the Northern Hemisphere, and from 0° down to -90° in the Southern Hemisphere. It is equivalent to the geographic latitude. The maximum Declination range of the Moon is ±28.73°. This will be the case in March / April 2006.

      The Greenwich Hour Angle is equivalent to the geographical longitude refered to the Greenwich Meridian (Origin). It is counted up westward, from 0° to 360°.

      The Distance shown here is the distance between the centers of both the Moon and the Earth. It is given in kilometers (km).

      The Radial Speed shown here is the speed of the Moon along the Earth-Moon axis. It is given in meters per second (m/s). When it is negative, the Moon is getting closer to the Earth. When it is positive, the Moon is getting farther. The Radial Speed is null at Apogee and Perigee.

      The Phase Angle refers to the Moon Figure. It is counted up from 0° to 360°. The phase cycle is traditionally divided in four parts, as follows:

      Phase Angle = 0°: "New Moon",
      Phase Angle = 90°: "First Quarter",
      Phase Angle = 180°: "Full Moon",
      Phase Angle = 270°: "Last Quarter".

      The Phase Angle is measured in the Ecliptic Plane, the plane of the Earth Orbit around the Sun.

      The Moon to Sun Angle is the angle made by the line joining the Earth center to the Moon center and the line joining the Earth center to the Sun center.
      At New Moon, if this angle is lower than 1°, there is a Sun Eclipse.
      Likewise, at Full Moon, if this angle is between 179° and 180°, there is a Moon Eclipse.

      This parameter is usefull around New Moon, because the sharper the antenna is, the closer to the Sun it is possible to operate.

      The line "Station" shows the call-signs of both stations (yellow for "Home", cyan for "DX"). The "Station List" or "Radio Telescope List" can be called respectiveley by "single-clicking" or "double-clicking" on either call-sign. See clause "Station Selection List Screen" for further details.

      Below the line "Station", the regular operating parameters are summarized  in a small table, as follows:
      1) Local time: this is UTC ± time shift due to position of station (see clause "Set Local Time" for further details),
      2) Local Elevation (degrees),
      3) Local Azimuth (degrees),
      4) Distance from Station to Moon "sub-station" point, on Moon surface (km),
      5) Radial speed on Station-Moon axis, as observed by both Stations respectively (m/s),
      6) Doppler shift as observed by both stations on their respective own echo. A special line also gives the "Mutual Doppler Shift", as observed by one station listening to the other station's echo. The Mutual Doppler Shift is the shift resulting from the combined motions: that of the Moon around the Earth, and those of both Stations relative to the Moon, due to Earth rotation.

      If either the "Home" Station or the "DX" Station is monitoring its own echoes, the receiver frequency must be set to that of the transmitter, corrected by the Doppler shift as indicated in either Station column.

      If both stations are trying to have a "Moon radio contact", they then have to tune their receiver at the transmitter frequency corrected by the Doppler shift as shown in the "Mutual Doppler" line.

      The lower part of the screen displays the following parameters: 

      
      1) Path Attenuation, in dB.
      2) Mutual and Complementary polarization.

      Path Attenuation:

      This is the theoretical "round trip" Attenuation. Fluctuations due to unpredictable atmospheric factors (and maybe others) are not taken into account.

      Note that the attenuation difference between Perigee and Apogee amounts to 2.3 dB, and this on any band.

      Mutual Polarization:

      The so called "Mutual Polarization" is the result of the Geometrical Polarization Rotation between both Stations, as seen from the Moon. Both mutual polarization and its complementary counterpart are given here. The resulting theoretical "extra" attenuation is also displayed. This parameter mainly concerns Stations using linear polarization and El-Az mounts.
      Warning: the Faraday effect, of different origin and essentially unpredictable, is not taken into account. This effect may either add to or cancel the Geometrical Rotation, leading to deep signal strength variations. This effect is not observed on the higher bands (5 GHz and above).

      On the lowermost line of the screen, a scroll-down menu allows selecting the frequency (or band) for which the Doppler Shift and the Path Attenuation are to be computed.

      The "Home" or "DX" Station Call-Sign (or Radio Telescope) List is opened by "single-clicking" on the displayed Call-Signs with the left button. The Radio Telescope list is called upon "double-click". Alternate access is also possible using the "Select Home or DX" menu. There is a short-cut possibility to access the Station List, as follows:
      <Ctrl Q> for "Home" station,
      <Ctrl A> for "DX" station,
      <Ctrl W> for "Home" radio-telescope,
      <Ctrl S> for "DX" radio-telescope.

      This Radio Telescope list is also provided, because some of them have been activated by radio-amateurs in the past (Arecibo in 1965, Nançay in 1989, for example), and others may be activated in the future.

      Greenwich and Paris observatories, which are not radio telescopes, are included for the purpose of comparison with ephemeris data related to those observatories. For example, at Paris on 1978 July 2, the Moon transit took place at 09:34:24 UTC according to the French Ephemeris "Connaissance des Temps". The software gives the same time.

*6
*7
STATION  SELECTION  LIST  SCREEN

      To open the Station Selection screen, "single-click" anywhere inside the "Moon Figure" screen or on the Call-Sign Label with the left button. This can also be opened through the MOON PARAMETERS Screen, by also clicking on the Call-Sign Label with the left button.

      A scroll List appears. The same List is selected, whichever the status of the screen, either "Home" or "DX". Once on display, the List screen can me moved anywhere. The background color is yellow for "Home", or cyan for "DX".

      To select a Station, either click with the left button on the wanted Call-Sign; if the wanted Call-Sign is not visible, move the scroll bar cursor until it shows up on the List, then single-click on it; or type the wanted Call-Sign in the text box above the list; every time a letter is typed, the list shows the first Call-Sign which contains the typed letter(s). A grayed preview display of the Call-Sign and Coordinates is provided in the display windows below the list. Double-click or type <Enter> to confirm the selection. The list then closes, and Call-Sign with Coordinates are displayed black. To close the list without any selection, click on the upper margin of the screen or type <Escape>.

      Default setting:

      Check the case "Default" for default setting. Everytime a Station is selected when this case is checked, it will be recalled when the software is later started "cold". Otherwise, the newly selected stations will be "lost" during a later start. The former "default" Stations will be recalled.

      Both Lists can be edited through the menu "Edit List". The editor "NotePad" is automatically called for that purpose. Every entry can then be modified or cancelled. New entries can be added.

*8
SET  LOCAL  TIME

      This option allows so-called Local Time to be displayed for both Stations on their respective "Moon Figure" screen, as well as on the "Moon Parameters" screen.

      Click on this menu and select the wanted correction needed to get Local Time, according to the longitude of the Station, or the country where it is located (most of European countries prefer arbitrary time shift, not in real relation with longitude...).

      Once the correction is selected, display of Local Time shows up on the lower left side of the Moon Figure. 

      Change Default setting(s):

      Check the case "Default" for default setting. Everytime a Local Time setting is selected when this case is checked, it will be recalled when the software is later started "cold". Otherwise, the newly selected Local Time(s) will be "lost" during a later start. The former "default" settings will be recalled.

      When the correction is cancelled (back to UTC), display of Local Time is also cancelled.

      If Default Computer Time is not set to UTC, UTC can be set back through the software without changing computer's internal clock settings. Click on the "Set UTC" sub menu.

*9
SET  UTC

      WARNING !

      Real Time mode and To-Day function are consistent ONLY if the software is run in UTC. "Universal Time Coordinated", official definition since 1978, is still better known as GMT, or "Greenwich Mean Time", although this last denomination should no be used any longer. The military "Z" or "Zulu" for UTC is also popular among hams.

      If the internal computer clock is set at local time rather than UTC, it is possible to run the software in UTC without changing the settings of the computer.
      Using the scroll-down list, choose the proper hour offset in order to come back to UTC. Displays of both Computer Time and UTC are provided, for checking purpose. Once UTC is properly set, click on the "OK" button. UTC correction is now defaultly recorded and will be recalled under "cold start" conditions.

      Example: a West-European operator has his computer clock set to UTC+2:00 during summer. In the scroll-down list, he chooses the value +2:00 to set back the software to UTC. This offset value is defaultly recorded once the "OK" button is triggered. This does NOT change the original computer clock settings.

*10
DYNAMIC WORLD MAP

      This map shows the Earth as seen by an observer "riding" on the Earth to Moon axis, at the date and time displayed in the date/time window. All EME stations recorded in the station file are shown as a small dot on the globe. Dragging the mouse over the globe shows its position (Latitude, Longitude and full Grid Square). Every time the mouse drags over a station dot, the dot is slightly expanded and the call-sign of the station is displayed.

      The "Home" station and the "DX" station are specifically "highlighted" with a small square and a line joining each station to the center of the map, which is also the "Sub-Lunar Point". An observer located at this point would see the Moon at Zenith. The angle made by the two lines is the so-called "station polarization angle".

      Moving left and right the cursor at the bottom of the map changes the time and makes the Earth rotate accordingly. The changes of the relative positions of the two stations become quite obvious on the map. "Medium speed" or "high speed" Earth rotation can be simulated using the left/right and page-up/page-down keys, when the map cursor got focus.

      The map can be moved across the main screen, and its size can be increased or decreased using the resize functions of the mouse, by clicking on the bottom right corner of the map screen and then, dragging the mouse. "Full screen" display can be choosen by clicking on the "max button" of the Map screen.

      Clicking on the "Default Map Size" sub menu restores the map to its default size and puts it back to its default position on the screen.

*11