Just Jupiter - The solar system's largest planet and its four major moons are all you get with this plain and simple utility.
By David Ratledge
SHOULD You BUY one software package that attempts to do everything or go for a range of small, specialized programs? It's a difficult call. The former might be easier, and ultimately even cheaper, but it could be a case of being a jack of all trades but master of none. JupSat Pro from Gary Nugent definitely falls into the second category. It's a one trick pony and, despite the obvious impression that its snappy title suggests, that trick doesn't include Saturn. It has no pretensions for covering anything other than Jupiter and its Galilean satellites: lo, Europa, Ganymede, and Callisto.
First things first: this software is not going to break the bank. It's available as a $15 download and, despite using a slow modem, I was able to acquire it in the time it took to make coffee. Installation was equally quick. After I entered a key code, JupSat Pro was up and running and I set out to determine when Jupiter, its moons, and the Great Red Spot would be best placed for imaging. The author chose not to follow the standard Windows look and designed his own interface. Despite the unique exterior, I had no problems with navigation and control. The provided electronic manual appears identical to the software's description on its home page, so you can read about all its features before risking your $15!
The special interface has a fixed-size window of 1,024 by 768 pixels. Consequently, the software doesn't benefit much from having a bigger monitor. Nevertheless, with a larger screen. you can position the program's other pop-up windows (discussed later) outside the main window.
The primary screen features two graphics windows and four text sections. At start-up the upper, bannerlike picture shows the standard binocular view of Jupiter and its four Galilean moons running in real time. The second graphic, called the View Window, can show rotating close-ups of the Galilean moons and Jupiter itself. The satellites are color coded for identification; the bottom text section includes the necessary key (this section also gives the distances of the moons from the planet in Jupiter radii - a sensible touch). The windows are synchronized and - here's the clever bit - the user controls them with a zoom (magnification) slider. You can quickly change the view from wide-angle, showing the extent of the moons' positions, to a close-up on the Great Red Spot and any moons (with their shadows) in transit across Jupiter. The views in the graphics windows can be oriented to match a particular telescope: inverted, mirror-reversed, or both. An icon allows easy stepping through all the permutations, and a compass indicates the current setting. For binoculars, this compass depicts west to the left - while this may be correct for Jupiter's atmosphere, it's opposite to the terminology most users would expect for the planet's environs.
The text sections are a mixture of useful information and a few data-entry fields. The former includes essentials such as position angle, phase, apparent diameter, and transit time. For accuracy, you must enter your location and the longitude of the Great Red Spot (94 degrees at the time of writing). Entering the time tripped me up at first. The real-time clock, which runs by default, must be stopped before you attempt a time change - I should have read the instructions! The animation interval can accelerate the clock, allowing a quick run through a night's (or week's or month's) events.
JupSat Pro has a better way of determining what lies ahead with three extra pop-up windows. These screens will be familiar to readers of Sky & Telescope's monthly planetary calendar (see page 59). The first is a timetable of the Great Red Spot's central transits for the current month. The second displays the phenomena of the moons - occultations, transits, and shadow transits - but just for the current day. The third shows a month-long vertical satellite-track diagram, a format that I consider the best way to quickly assess forthcoming moon alignments. These pop-up windows are the real powerhouse of the program and enable the planning of observing sessions to catch the best events for the month ahead. Unfortunately, like JupSat Pro's main window, these side screens cannot be printed. That's a shame, as it would be most useful to take such results out to the telescope.
I experienced a few irksome niggles. First, though the Jupiter banner view could be flipped to match a user's telescope, the satellite-tracks chart always corresponds to a Newtonian reflector's inverted view. Second, when the planetary-view window displays a close-up of Jupiter, it shows the Great Red Spot beautifully but the moons and their transits disappear. Finally, and perhaps most important, the program doesn't calculate eclipses of the moons by Jupiter's shadow.
I found JupSat Pro a neat utility that delivered what it promised - nothing more, nothing less. In these days of bloated complex software, it's great to come across something that lives up to the KISS philosophy: keep it simple, stupid. I can't wait for a logical sequel: SatSat Pro!
What We Like:
- Very easy to use
- Excellent display os moon transits and the Great Red Spot
- Pup-up windows for forthcoming events
What We Don't Like:
- Doesn't calculate eclipses by Jupiter's shadow
- Doesn't print output
Whether contributing editor DAVID RATLEDGE succeeded in imaging Jupiter, its Great Red Spot, and its moons, could well be disclosed in the new book he has just finished editing, Digital Astrophotography: The State of the Art, to be published by Springer in mid-2005.
JupSat Pro Author's Note: Sky & Telescope reviewed an earlier release of JupSat Pro (V1.32). The current version of the software (V1.70) does now calculate the times for satellite eclipses by Jupiter's shadow and the satellite tracks diagrams and Great Red Spot transit times can now be printed out.
Scanned Images of the Sky & Telescope Review
Filed under: Astronomy Software