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- From: sterner@warper.jhuapl.edu (Ray Sterner)
- Subject: PC Starchart/Planetarium program review.
- Message-ID: <sterner.721430390@warper.jhuapl.edu>
- Sender: news@aplcen.apl.jhu.edu (USENET News System)
- Organization: Johns Hopkins University
- Date: 10 Nov 92 21:19:50 GMT
- Lines: 166
-
- Starchart/Planetarium program for IBM PCs and compatibles
- ---------------------------------------------------------
-
- I was digging around on the network a while back and came across
- an excellent starchart program for IBM PCs/compatibles. The
- program has too many features to give a full list here but I will
- describe some of them below.
-
- The program is shareware and is one of the truely great bargins at
- $20. It runs very well on my 386/25 monochrome LCD notebook computer,
- but I didn't know about the colorful graphics until I ran it on our
- 486/33 at work. The program is very well written and a user's manual
- is included in the *.zip file.
-
- The program is not available on non-IBM compatible computers, such as
- Macintosh. The documentation states that a lot of the code is in
- assembler, great for speed, but not for portability.
-
- This program would make a good Holiday or birthday present for anyone
- interested in astronomy that has the right computer.
-
- How to get the program
- ----------------------
-
- I found the program on an anonymous ftp site. The commands are:
-
- ftp wuarchive.wustl.edu (Washington University, St. Louis, MO)
- (I don't have a list of other archive sites that have this program.)
- For name enter: anonymous
- For password enter: your email address
- Change directories: cd mirrors/msdos/astronomy
- Set to binary mode: binary
- Download: get skygl352.zip (that's SKYGL, not G1, but lowercase).
- (check the name, the version number changes with updates.
- To get a directory listing do: ls)
- Exit ftp: bye
-
- Unzip the zip file on your PC. The program runs under MSDOS and Windows 3.X.
- The user's manual has Windows setup instructions.
-
- If you can't download the software from a BB or archive site you can
- call the company direct (KlassM SoftWare) and order it.
- The number is: 1-800-968-4994, its the best software buy at $20 I've
- seen so far.
-
- Educational site licenses are also available.
-
- A description of the program
- ----------------------------
-
- The program has a very large number of options. One nice feature that
- makes this number manageable is that option control keys often cycle
- through a number of closely related options or levels.
-
- Here is a list of some of what the program displays:
-
- Objects
- -------
- Stars: number selectable from 300 to 25000. White and gray.
- Sun/Moon/Planets: the Sun, Moon, and all 9 planets may be displayed
- with or without names. They may also be turned turned off completely.
- Appropriate colors, Jupiter has a red spot, the Moon shows quarters.
- Milky Way: may be displayed in 2 shades of gray or blue or just as
- contours of 2 levels. If gray or blue is used both the fainter and
- brighter parts of the milky way may have their intensity adjusted.
- Deep sky objects: all Messier objects may be shown, plus some NGC objects.
- All may be turned off. Objects may be turned on at one of 5 levels
- of completeness. White.
- Coordinates
- -----------
- Horizon: The horizon display may be cycled through the following:
- off, Horizon only (with direction labels), +zenith, + 15 deg altitude tics.
- Horizon in green, zenith and tics yellow.
- Ecliptic: on or off. Orange.
- RA and Dec lines: off, 3 hrs/45 deg, 1 hr/15 deg. Gray.
- Labels
- ------
- Stars: off, brightness sequence number, names, names (bold).
- The number of stars labeled may also be controlled. Orange.
- Constellations names: off, 3 letters, small text, large text. White.
- Lines
- -----
- Outline: off, screen, round map area. White.
- Constellations: constellation lines may be cycled through several
- levels, from asterisms to major constellations to all constellations.
- One key toggles the current setting completely on or off. Orange, red.
- Constellation boundaries: on or off. Orange.
-
- Here is a list of some of what the program does:
-
- Date and Time: may be incremented or decremented by 1 minute, 1 hour,
- 1 day, 1 month (30 days), 1 year, 1 century, 1 millenium. Its not hard
- to select a certain date and time.
- Zoom: May zoom in or out. At full zoom the Keystone of Hercules fills
- the screen. With all 25000 stars turned on I counted 18 inside the
- Keystone. At minimum zoom the entire sky is a small circle on the
- screen.
- Pan: May pan around the sky using the arrow keys. The mouse makes it
- even easier, just click on a point to center on the display.
- Location: may select from a large number of locations around the world.
- May also move in steps from selected location.
- Find: may find and center on the display the Sun, Moon, any planet,
- many stars, constellations, deep sky objects.
- Twilight mode: brightens the sky background while the sun or moon is
- above the horizon. The background darkens as the sun drops lower in
- the sky and below the horizon. The moon has a similar but smaller
- effect.
- Turbo mode: repeat a command until stopped. This is really the highlight
- of the program and will be described next.
-
- Animation:
-
- SkyGlobe even without animation would be a bargain, but it is designed
- to show the motions in the sky and does this very well. One very nice
- feature is the real time mode which shows the sky as it currently is,
- updating the display once each minute. I've watched the sun cross the
- sky on a rainy day while I worked on another computer.
-
- The really fun animation is done using the turbo mode which repeats any
- command. Using turbo mode to increment time by 1 day follows the sun
- on its path along the ecliptic as the background stars slide behind it
- in their westward drift. The orbits of Mercury and Venus around the
- sun become quite a bit more obvious. If the time increment is set to 1
- sidereal day the stars appear frozen while the Sun, Moon, and Planets
- move across the sky.
-
- A new feature in the latest versions (3.52 has it) is the ability to
- track any object. I was going to suggest this addition but it appeared
- before I could, the author seems to know just what to add to make the
- program an excellent teaching tool. I tried tracking on Mercury
- after zooming out to show the sky as a globe and minimizing the
- number of stars to get the fastest speed. The program preserves up and
- down at the center of the display, that is, the display is in
- altazimuth coordinates. This gives some really wild animation when
- tracking on Mercury.
-
- I also used turbo mode to watch the sun trace out an analemma in the
- morning sky. Combined with a VGA projection system such a demonstration
- would be a good way to explain to an astronomy class such things as why
- the year's latest sunrise doesn't happen at winter solstice and other
- related topics.
-
- I found an interesting grouping of Solar System objects using turbo
- mode. Seven objects come together in a group less than 10 degrees
- across. This happens on 12 Jan, 1994 (at about 0:00 UT to include
- the moon about the best). Use the program to view it from the South
- Pole. The objects are: Moon, Mercury, Venus, Mars, Uranus, Neptune,
- and, unfortunately, the Sun (which makes it all invisible).
-
- Turbo mode may be used with other commands, such as Pan or Zoom (gives
- a Startrek Warp-like effect). The number of stars displayed may also
- be animated using turbo mode. Precession is nicely shown by incrementing
- by centuries or millenia.
-
- Conclusion
-
- This is shareware at its best. The author of this software is well
- worth supporting, especially if it allows him to produce other such
- excellent programs. I would recommend this program to any amateur
- astronomer with an IBM PC or compatible computer. Also to any science
- class that deals with astronomy, from grade school up to college.
-
- Ray Sterner sterner%str.decnet@warper.jhuapl.edu
- Johns Hopkins University North latitude 39.16 degrees.
- Applied Physics Laboratory West longitude 76.90 degrees.
- Laurel, MD 20723-6099
-