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Monday, May 21, 2012


For many months back in 1995, I wrote the “Don’t Try This at Home” column for Computer Life magazine, one of several Ziff-Davis titles to which I contributed. Here’s an example of what the column covered, finding novel ways to connect computers to other tasks. At this point, the idea of controlling a home-use telescope with a computer was still fairly new, if expensive, but you can still get a Meade LX-200 for about $2,500, and the versions of TheSky software have changed, but the entry-level telescope-controlling package is now less expensive than the one I reviewed. Much else also has changed in the interim – who deals with serial ports any more? – but the night sky remains a source of wonder and mystery.


Meade LX-200
IF YOU LISTEN TO the songwriters, the stars are big and bright in Texas when they're not falling on Alabama, no doubt wrenched from Vermont where there's only moonlight reported. But if you stand outside on a clear night and look up, a sparkling canopy of mystery awaits your study. Thanks to the ancients who had no streetlights and lots of time on their hands, we have fancifully-imagined constellations to consider, not to mention solar system objects and the more recently-catalogued phenomena like star clusters and distant galaxies.

These days, each time bright Venus rises, the number of UFO reports generally goes up. No professional astronomer makes that mistake, and, thanks to a happy combination of telescope and computer, neither will you.

Many fine astronomy programs are now on the market, giving planetarium-like tours of the heavens. And there are computer-telescope combinations in addition to what I describe below. But where the others combinations merely help you to aim that telescope barrel, Software Bisque's TheSky actually feeds the Meade LX-200 telescope the information it needs to position itself, telling it to center its focus on the object of your choice.

It's the kind of thing that makes old-line astronomers grumpy. You haven't earned the view of that object by skewing the scope by hand, hour after hour, to learn every square inch of what's up there. But isn't this exactly the kind of drudgery computers are supposed to spare us?

Besides, this experience will definitely spur you to learn more about the night sky. We all know how to spot Orion and the Big Dipper, and the fiery blue twinkle of Sirius cuts through even the lights of a city. Using this telescope and software, however, you can't help but pick up on the names of more stars and constellations. And the view up there changes hour by hour, even as the moon and planets reposition themselves (according to our point of view) day by day. TheSky tracks those changes, letting you know what's up there right now or how it will look any time in the future or past. Thanks to the information I gained from a virtual time-travel journey with the software, I was inspired to get up an hour before dawn the other morning so that I could watch the rise of Venus and Saturn in the east before the sun rose and obliterated everything.

You get more than just a planetarium picture. Tell TheSky where you live and the time of day, and it calculates the heavenly view. Use the Time Skip feature and you'll see what the view will be in an hour or two (or more). A yellow horizon line shows what's rising at sea level; you can draw your own horizon line to reflect what's blocking that view.

TheSky, with convenient horizon
TheSky software comes in several versions, so be sure you choose the Remote Astronomy package. When you crave more in the way of heavenly objects, though, there's a CD-ROM-based version that incorporates information captured by the Hubble telescope, giving a database of 20 million things in the sky.

Although the LX-200 telescope looks stubby (but don't be fooled--it's heavy!), it actually sends the light bouncing three times the length of its tube thanks to a clever arrangement of mirrors. By the time it hits the eyepiece, significantly more of that light has collected. Which means that this telescope will show you pinpoints of light that you've never seen with the naked eye, and that you'll be able to see formations of comparatively weak magnitude, so browse TheSky's listing of Messier objects--those nebulae and clusters that make outer space seem all the more wonderful and mysterious--and make a shopping list for your observation sessions.

This has been a treat for my household and the neighbors, who quickly learned to gather in my yard whenever the skies were clear. With the telescope in place, aligned, and connected to the computer, I found Jupiter on the computer screen and instructed the telescope to skew to find it. We were greeted with the image of the planet's radiant disk closely surrounded by its four brightest moons, which is a startling sight.

Setting it all up is straightforward, but it's best done during the daytime when you can see well enough to set up a table and to stash the wires away--which can be done by placing a piece of heavy carpet over them. Keep in mind, though, that the greatest potential danger with a telescope this powerful is a glimpse of the sun during daytime. Even a momentary glimpse can cause blindness. I read the cautions, dismissed them as over-fussy--who's going to look at the sun?--and almost swung the scope right at it as I followed the track of a jet through the daytime sky.

I'm looking forward to the dark nights of late summer when the band of the Milky Way spreads across the sky and I can probe that band of galaxies and dust. It even gets a little spooky when I'm confronted with the evidence of so much else in the universe and reason that somebody, somewhere, hidden amidst those stars, has a computer-guided telescope aimed back in my direction and is also wondering just who else is out there.

Step 1: Install the Software

Start Windows on your computer. Insert the first disk of the TheSky software into you’re a: drive, pull down the File menu and choose Run. Type "A:INSTALL." Confirm the directory TheSky suggests, and change the disks when prompted.

Step 2: Configure the Software

Before you even start the program, set your computer's date and time correctly. Never mind what it already says: go to an atomic clock. If you're a shortwave listener, you already know how to tune WWV; otherwise, call 303-499-7111, keeping in mind that the number you get will be Universal Time, and you'll have to adjust it for your time zone. With Daylight Savings in effect, my location is four hours behind. Type TIME at the C:\> prompt and enter the correct time (using 24-hour time format). Now run TheSky and choose Date & Time from the Input menu. Check the box marked Use the System Date & Time, and check the Daylight Savings box if necessary (it's in effect until the end of October). TheSky also needs to know your location. Latitude and Longitude can be tough to find, but the numbers show up on certain road maps and atlases. I had to extrapolate from a small map of New York State, but with the info in hand, I pulled down TheSky's Input menu and chose Location, then typed in a longitude of 74 degrees 25 minutes west, latitude 42 degrees 55 minutes north. I typed my town name into the Description box, clicked Add to File, clicked Set to Current, and then selected OK.

Step 3: Set Up the Telescope.

The LX-200 is in two main parts: tripod and telescope. Set the tripod on a hard, level surface, choosing an area that isn't too saturated with artificial light. The telescope itself has two handles; with a friend to grab the other handle, lift it from its case and set it on the tripod, aiming the threaded center shaft into the corresponding slot on the bottom of the scope. Be sure that the tripod spreader arms are pushing against the legs of the tripod. Tighten the center shaft until the scope is firmly engaged. Remove the covers at each end of the telescope barrel. Thread the eyepiece holder onto the smaller of the two openings, and slide the narrow end of the diagonal prism into the eyepiece holder. Tighten the set screw on the side of the eyepiece holder, taking care not to overdo it. Slide the eyepiece into the shaft by the prism, and tighten the appropriate set screw. For help in centering objects, mount the viewfinder (it looks like a mini telescope) by sliding it into a groove near the top of the telescope barrel and tightening the set screws.

Step 4: Level the Telescope.

Proper alignment begins with a level telescope. There's a bubble level built into the base of the scope, so use that as a guide as your helper loosens one or two tripod leg extensions and slowly raises or lowers the whole assembly. Don't hurry this process, and don't overtighten the set screws on the tripod legs. Next, angle the barrel of the telescope until it’s horizontal. Looking from the rear, a protractor guide (called the declination setting circle) on the left-side hinge has a zero point that lines up with the base when the angle is correct. Tighten the locking knob on the right-side hinge. Similarly, rotate the telescope so that the pointer at the base of the hinge fork is lined up with the pointer above the control panel. Swing the thumb lock next to the pointer to the left until it’s locked.

Step 5: Make the Power Connections.

Run an outdoor-quality extension cord to a clear, flat area away from distracting lights (and when you're sky watching, all lights are distracting). Plug a power strip into the end of the cord, and plug the telescope’s power transformer into one of the power strip outlets. Plug your computer’s power supply into another. At the other end of the telescope transformer is a small barrel plug; plug it into POWER jack on the telescope’s control panel. The telescope has two motors, only one of which is in the base; the other motor is in the fork that holds the telescope barrel. Connect it to the base by plugging a coiled wire with a telephone-type plug at each end into jacks marked DEC MOTOR on the control panel and on the fork.

Step 6: Connect the Telescope to the Computer.

Plug the serial port adapter that comes with TheSky into a serial port on your computer, taking care not to interfere with your pointing device (you’ll need it!), and run the wire from the adapter to the telescope’s control panel, plugging into a jack labeled RS232.
Use the telephone wire that comes with TheSky to connect the computer to the telescope, with a serial port adapter that comes with TheSky software. Plug the adapter into a  Two slide switches sit at the upper right of the control panel; one, with ends marked N and S, is set for your hemisphere, so I left it at N; above it is the power switch. Switch it on. You’ll see the control panel spring to electronic life with an assortment of red LEDs.

Step 7: Establish a Data Connection.

Pull down TheSky’s Telescope menu, and select Data. Choose the COM port number in the pull-down box labeled Communication Port; confirm a baud rate of 9600 in the next box. In the Communication Box, select Meade LX-200 series from the pull-down menu. Click OK. Pull down the Telescope menu again and select Link; from the next menu, select Establish. When the link is successful, a small yellow-rimmed circle appears on the screen, corresponding to the view in the telescope eyepiece.

Step 8: Align the Telescope.

Study TheSky’s display, and choose a view that corresponds to what you're seeing above you. Find a particularly bright star (not a planet) that you can recognize both in the sky and on the computer screen. I used Arcturus, which you can find by following the arc of the handle of the Big Dipper to the next bright star. Pull down the Telescope menu and choose LX-200 Options; from the next menu, select Controls. A small box appears with four directional buttons; use them to slew the telescope to the star you've chosen. The four radio buttons below the directionals control the speed; Slew is fastest, Guide the slowest. Use the viewfinder to help center the object. When you've got a good view of it in the telescope, go to your computer and point and click on the onscreen equivalent. An information box pops up; from the buttons on the bottom click on Sync Scope. The little yellow circle--called a reticle--jumps to surround that object, and you're aligned.

Step 9: Find a Cluster.

To preserve your night vision, pull down TheSky’s Options menu and choose Night Vision Mode. This throws the display into red. It’s an eerie effect, but helpful. What you can see depends on the time of year and the time of night, but some of the more striking objects are clusters. Hercules is high in the sky this time of year, so look for the large globular cluster in that constellation. Choose the Find button from TheSky's toolbar. Type "M13" and press Enter. A data screen pops up; select Slew To. The telescope will move to give you a view of it. It appears as a bright, circular smudge if you're using the 26mm eyepiece that comes with the LX-200. Others worth trying are M3 and M51 in Canes Venatici and M5 in Serpens, and keep an eye out for Jupiter: it doesn't set this month until after midnight, so you can get a good look at the four moons that surround it.

Mt. Wilson's view of the spiral galaxy M51
Step 10: Call the Mount Wilson Observatory.

TheSky's telescope control doesn't end here. You can call the 24-inch telescope at the Mount Wilson Observatory in California and control it from your home machine. It's the same procedure, but the result is captured as a computer image file and downloaded to you. The program is part of the Telescopes in Education program, and it's free to schools (grades K-12); the rest of us pay at a rate of $50 per hour. To set up an appointment, call 818-793-3100.


Have a friend help you. That telescope is heavy!
Get a couple of outdoor-quality extension cords.
Set up your area in daylight; include a table and chair.
Get a piece of old, heavy carpet to cover the wires running between telescope and computer.


Don't ever look at the sun through the telescope. Use extreme caution when daytime viewing.
Don't adjust the telescope's position by hand once the motors are activated.
Don't wave flashlights around while setting up--you’ll ruin your night vision.

You'll Also Need:

Extension cords
Transportable computer
Red flashlight
Power strip
Table and chair
Old piece of carpet

Product information:

Software Bisque
912 Twelfth Street
Golden, CO 80401
1-800-THE SKYW
(303) 278-447
TheSky Remote Astronomy Software, $295.00 (School price: $200.00)
LX-200 Serial Connector, $25.00

Meade Instruments Corp.
27 Hubble
Irvine, CA 92618-4209
(949) 451-1450
LX-200 Schmidt-Cassegrain Telescope (8-inch), $2,495.00

Computer Life, July 1995

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