Main screen for LunarPhase Pro.

Do you remember when you were a kid and wanted one of those fancy Swiss Army Knifes? There in one red package you could have a saw, scissors, tweezers, toothpick, bottle opener, file, slotted and philips screwdriver and even a knife blade! Well LunarPhase Pro (LPP) doesn’t have the fat red case, but it does take the same approach to Lunar software.

The opening screen shows the moon with current phase and the correct libration, with a marker for the point on the lunar limb that currently is at maximum libration. This view can be set for flipped or inverted views, depending on what you use to observe the moon. Around that are listed the time and dates for the four different quarters (new, half, full, half), percentage of the moon currently illuminated, age, current distance, RA & DEC, Alt & Az, angular diameter, time and date of apogee and perigee, time of today’s moonrise, moonset and transit, sunrise, sunset and sun-transit time, twilight start and ending time (civil, nautical and astronomical) and colongitude. Additionally, a table of libration data adds North-South libration, East-West libration, degree of maximum libration, position angle for that libration and the moon’s current position angle. But even more amazing is that all of this data is clear and available at a glance, due to the clear layout employed.

A dropdown menu accesses features to find lunar eclipses within a specified timeframe, display a calendar with phase for each day, lunar features database, Equinox & Solstice dates, Internet links, basic lunar data and other features which will be described below.

As I mentioned, the opening screen tells the current libration, both graphically and in table form. LPP corrects its maps for the current libration.

LPP takes it several steps farther. Clicking on the Moon Explorer button brings up a large image of the moon with current libration. But if you click on the start arrow, the phase and libration shifts to the first of the month. From there, it plays like a movie, with the terminator moving across the surface and the moon shifting to show the proper libration at each point. A clock at top shows the date and time for each frame in the animation. At this point in the review process I ceased to be a lunar observer, and became a kid with a new toy. This has to be the coolest feature! There in front of you sits the moon, rocking back and forth with the small libration changes caused by the observer’s movement as the earth rotates. And overall is the much larger movement of a month’s worth of libration changes, played out before you. It is fun to just sit and watch favorite craters move up into view and back towards the limb. Even more centrally located craters like Tycho, Plato or the larger Mare Crisium move in and out, changing in apparent shape as they go. I confess I played with this for a long time before moving on to checking out the other features!

Along with the libration movie and the libration data on the initial screen, there is a clear graph showing the direction and amount of libration for each day of the month. This can be presented for a geocentric position or your actual geographical location. Again, the small loops caused by the earth rotating the observer from horizon to horizon are superimposed on the larger monthly libration movements. Those wanting to observe features in the libration zones can quickly print out the libration results for the full month.

LPP presents the actual libration for the current moment but also gives you additional tools and data for planning your observing sessions.

This is illustrated by the second major feature I discovered (and the one that is rapidly becoming my favorite). Instead of simply listing lunar features, LPP presents them with the date and time for sunrise and sunset at each of those features. Printing this out is a big help for planning. For example, in writing this month’s Lunar Feature of the Month [LFM] (on Tycho) I wanted to point out a swirl of craters that are near Tycho. They are only prominent for a few hours, when the terminator has passed them but not gone much farther. Looking up a crater that was where the terminator would be for best viewing of this cluster of craters, I checked LPP and found the date and time (my own local time) of sunrise for that crater. This was then included in the LFM article, as well as in my own observing session plans. In the same manner, if you wanted to observe or photograph Rupes Recta at sunrise, a quick check would tell you when sunrise will occur. I am presently printing out the sunrise and sunset data for all the listed features each month. It only takes a couple of pages but is very helpful!

The accompanying visibility charts also help with planning by showing how high above the horizon the moon will be at those particular times of sunrise or sunset on the features I want to observe. Also listed are the moonrise, moonset and transit times for each day of the month in question.

Once you go out to the scope, the Lunar Explorer Screen will come into play. This presents a map of the moon, corrected for libration. The map and the ability to identify features works both directions. That is, you can click on a feature on the map, and LPP will give you the name and information about that feature. Or, you can go through a list of features and click on a name. The corresponding feature will then be highlighted on the map. Lists are broken down into 19 categories, including craters, maria, spacecraft landing sites, domes and rima. An additional category lists all of those items which are currently on the terminator.

Easily accessed buttons scroll the display to center the section you want to observe. A slider at the top will change the zoom so you can zoom in on a detail, or drop back to have the full moon in the display. Shortcut buttons will zoom to the 4 lunar quadrants and a North or South Pole view.

An additional feature is the map of the moon’s far side. LPP is the only one to include this interesting (and fun!) ability. All of the features work on the far side so you can zoom in, pan, identify features etc. The map can also be flipped or inverted to show the view as it will appear in your scope.

LPP is outstanding value. LPP adds a great lineup of tools to plan your observing sessions (lunar feature sunrise/sunset times, visibility charts, libration charts), as well as the cool libration movie. The cost is only $40. You can also download a simpler version (Lunar Phase) as shareware ($30 registration and any registered LP user can later upgrade to LPP for $15). Bear in mind that this is a simpler version and does not have all of the planning features of Lunar Phase Pro. I think you will find the additional features in LPP to be worth the $40 expense.

Clear Skies and enjoy the Moon!

– Chuck Taylor – Moderator: Yahoo Lunar-Observing List

Filed under: Astronomy Software