As I begin this article, I'm imagining that I'm on a satellite of Mars called Phobos, and I'm watching Mars, which looks like an enormous crescent, eight times the size of the Big Dipper as seen from Earth. Such imaginary wanderings can now take place from within my home, with the help of a wonderful CD-ROM planetarium simulator called RedShift (about $60 street price), created by Maris Multimedia in the U.K. and published in North America by Maxis Software.
RedShift offers all the features of a normal planetarium simulator. Its stellar database includes stars as faint as the 12th magnitude, giving you around 250,000 stars to explore. Should you tire of stars, you can also explore some 5,000 asteroids, 100 short-period comets, and 40,000 deep sky objects (such as nebulae, star clusters, and galaxies). Using RedShift, you can place yourself anywhere on Earth at any time or in any era, and view the sky as it was (or will be) then and there. The program also takes precession into account; that's the extremely slow wobble of our planet's axis over the millennia.
With the possible exception of the enormous database of stellar objects, you might expect such features from any real life planetarium in any major city. RedShift takes another exciting step: it gives you the ability to observe the night sky anyplace in the solar system within 100 AUs (Astronomical Units, or 93 million miles) of the Sun. Not only can it put you on the equator of any of the planets or several of their moons, it can also put you at any point in space within the solar system. You can watch the universe revolve in real or accelerated time, and take advantage of this unique opportunity to watch a planet as it sweeps by you in its orbit. As a bonus, the CD-ROM includes detailed maps of the Earth, Moon, and Mars, giving you the ability to view the sky from the same perspective as Viking 2 on Mars or Tranquility Base on the Moon, for example.
The program also allows you to record your own still images or QuickTime movies. Take a picture of the sky on your birthday to show friends, or record a QuickTime movie of Venus transiting the Sun to enhance your classroom astronomy lesson.
While other planetarium simulators allow you to view conjunctions and eclipses you already know about, RedShift allows you to calculate when the next ones will appear. Was the Star of Bethlehem really a conjunction of several planets in the night sky of the Middle East? Set it up and you can decide for yourself.
RedShift also acts as a multimedia astronomical encyclopedia. The CD contains the full text of the revised and updated Penguin Dictionary of Astronomy by Dr. Jacqueline Mitton. This text has been enhanced by hypertextual links, additional illustrations, and animation. The dictionary interface enables you to browse around via both the contents and an index. You can also access it by simply clicking on the object the screen that you want to find out more about. A dialog box will appear and give you access to the dictionary among other reports.
Finally, Maris Software has marketed this product in a format that I look forward to seeing from other companies: the Windows, Macintosh, and Power Macintosh versions of the program are all included on the same CD-ROM, thus eliminating any confusion about what platform the CD-ROM will run on when you buy it and offering the maximum flexibility in deciding where to run the program. In doing this, Maris has given its customers a truly "plug and play" solution and I commend them for it.
No program is perfect, and as wonderful as RedShift is, there is room for improvement. The software's handling of time, an important concept in astronomy, could be better. The program reads the system's clock and map control panel to determine your location and time zone. This causes problems during the summer when most people switch to Daylight Savings Time; to get around the problem you must manually modify the difference in the number of hours between your time zone and Greenwich Meridian Time. Also, when you place yourself on the surface of other planets and moons the program mandates that only Greenwich Meridian Time has meaning. Unfortunately it then insists that your computer's system clock shows Greenwich Meridian Time which, unless you live in England, is not the case. I've worked around this difficulty by using the shareware World Time Control Panel to temporarily change my system's clock to Greenwich Meridian Time when I need to.
Since starting to review CD-ROMs I've found that their quality varies quite a bit. Some have not been worth the plastic expended to print them, while others embody the reason CD-ROM technology has taken the industry by storm. RedShift falls into the latter category. It shines like Venus in the early evening sky. This is one CD that justifies your CD-ROM drive in the first place! Although its handling of time is a blemish in an otherwise outstanding product, it can be worked around. If you have any interest in astronomy, RedShift would make a fine addition to your CD-ROM collection.
Maris Multimedia Ltd -- 800/336-0185 (US) -- 44-71-488-1566 (UK)
44-71-702-0534 (UK fax)
Maxis -- 800/336-2947 -- 510/254-8700 -- 510/253-3736 (fax)