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MARS IS COMING
It's not the closest approach in nearly 60,000 years, but it'll be darn good
And you should have the best possible optics!
Mars is largely a dud without really good optics and now is the time to get going. Things will get busy in a few months. Get a head start and order now.
Observing Mars is also a skill in itself. See below on how to do it.
"A steady atmosphere is essential to the study of planetary detail: size of instrument being a very secondary matter. A large instrument in poor air will not begin to show what a smaller one in good air will." - Percival Lowell
The picture above is something to aspire toward seeing
visually on a good steady night with an 8 inch mirror or larger. One of many
fine images taken by Eric Ng of Hong Kong. Click on picture to see larger image.
Mars Events
Put up and maintained by Dan Bruton and located at http://www.physics.sfasu.edu/astro/mars.html. Full of good stuff, notably, you can find the stellar position of Mars and other planets in RA and Declination at any time. Lots of excellent links. Main page is http://www.physics.sfasu.edu/astro/
Maps
The first thing one needs is a good map, ALPO has a nice maps and is one of the pre-eminent sites for Mars information, as well as a wonderful source for other planets and the moon; a wealth of information - dive in.
Other organizations with Mars information include the British Astronomical Association at http://www.britastro.org/observe.html with a specific Mars section at http://www.britastro.org/index.html. They're not talking about the 2003 opposition yet, but they'll get there soon.
Views of the Solar System is an extensive web page by Calvin J. Hamilton that covers all of the planets plus the moon, sun, the asteroids and anything else that is known to be orbiting, drifting or just generally hanging around the solar system. If it's out there Calvin has got it in his site and has written about it and likely found pictures of it. The main site is at http://www.solarviews.com/eng/homepage.htm the specific Mars site at http://www.solarviews.com/eng/mars.htm
Observing
Mars takes a little effort to observe properly. One fellow I knew years ago referred to it as, "A fried egg at 500 feet." You can't just put an eyepiece in and look. Mars requires patience and a serious approach. You have you study it with the proper tools: an optically good and well collimated telescope of 6 inches (preferably 8 inches) or larger, a Barlow lens (avoid those above 3X magnifying power), good simple eyepieces (not Nagler four-pounders) and the proper filters. Frequently, Mars looks like a bright, featureless little blob in amateur telescopes. No wonder people become frustrated and disinterested in this planet. Magnification should be at least 150X in any case and up to 200X for a 6" instrument, 250 for an 8" and 300 for a 10". Beyond that its up to the atmosphere and having a very good night. Good optics play an important part and having the right filters and eyepieces. Actually, the eyepieces need only be simple; Plossls are my favorite. The field lenses are not near the image plane so dust and dirt does not come into focus and there are few elements to scatter light and reduce contrast. Use a Barlow lens to increase power rather than very short focal length eyepieces. Cut down the light intensity with neutral density filters. The adjustable Orion moon filter is very good for bright objects like Mars and Venus. Having too much light is detrimental to good observing. I have actually observed Mars with an uncoated 10" mirror and the illumination level was perfect. Color filters are important for bringing out certain kinds of features and enchanting contrast. Try them all; red, orange, yellow and yellow/green are good for darker surface features; blue is good for seeing clouds. Clouds are usually seen on the eastern limb as the Martian sunrise thaws ice into water vapor. For a more thorough discussion of observing essentials see Observing Essentials - What you really need to get the most out of high resolution observing.
Observing the Moons
Want to try for the moons? You should have at least a 10" telescope to see Deimos. Phobos will require a larger instrument, about 15 to 18 inches. The exact positions of the Martian moons for any time can be found at http://space.jpl.nasa.gov/ . This site will allow you to exactly predict when the moons will be visible. For a picture of what you will see click here. One must realize that these moons move very rapidly and if you are not observing within about 20 minutes of optimum even Demos (the outermost planet) will move sufficiently away form greatest elongation to be lost in the planet's glare. Once you begin operating the program, set the time and date of you next observing session. Set the "I want body to take up" box at 10% and under Options click on Planet Orbits, Satellite Orbits and Extra Brightness. Ask for extra brightness in order to see orbits. Adjust the dates and times until you find a date and time where a moon (I'd stick with Deimos, at least at first) is at greatest elongation and it's some convenient dark hour. I have glimpsed Deimos with my 10" reflector and that's about the smallest aperture size I'd recommend. When observing, high magnification might well be advisable as it darkens the sky and actually allows one to see fainter objects. It might also cut down the glare from the planet. If you can rig up an occulting bar, try that or keep the planet out of the field of view. I have never had good luck with occulting bars since they seen to cause a glare that blots out the faint satellite.
A Moon Sighting
On Wednesday night, April 21, 1999, I went out and made a concerted effort to observe the moons. These are very difficult objects but at 12:35 Eastern Daylight Time, I saw 13th magnitude Deimos. It's the littlest star I've ever seen, really tiny. It will come in at four diameters of Mars at greatest elongation ever so faintly. You may glimpse it briefly, for perhaps 2 or 3 seconds and then it will slip away. I was not using any filter or occulting bar. Tried putting the planet out of the field, but no dice. I saw it maybe four times for certain. Phobos is one diameter from the disk, too close to pick up, but I have plans to try again. The best was to put Mars just off the center of the field and scan around the center of the field where it ought to be. I was using a 10" f/8 with a newly coated mirror at 450X. Lower powers were not as good. (Increased magnification actually darkens the background and lets you see fainter objects.) Went out again at 1:15 AM and saw it again just once. Sky went bad. High streaks of thin stuff moved in.
It was a very exciting experience. One needs a really transparent sky. The intrusion of the clouds killed it. And I emphasize that it was the merest of flitting little thing, one step removed from the, "Nah, I'm having illusions," level of observing. I'll want to be able to see it again before I feel really good about it. For the 2003 opposition I plan to make and try an occulting mask out of aluminum foil that will cover about 1/3 of the field. I can then rotate the eyepiece to cover the correct side. The object is so faint that seeing as well as transparency become important. If the seeing is bad, the spurious disk will explode and the effective magnitude drop below the visibility threshold.
I'd love to hear that someone else saw it. It was more like deep sky observing than planetary. But I swear I saw it. I worked on this about one hour so don't get discouraged right away. Anyone with a 12.5" should be able to see it if the optics are clean. Scatter is your enemy here, but concentrate your vision away from the planet. You have about one half hour to look at it before it begins to dive back into the planet.
I will report more as I work on various techniques for revealing the illusive horses of Mars' chariot.
Books
One can now download books directly from the Internet for free and two are available that deal with Mars. A fun read is Lowell's grand classic Mars from 1895. It's full of information from the favorable 1894 opposition and is published on the Web by Bibiliomania at http://www.bibliomania.com/index.html. The Mars book is specifically at http://www.bibliomania.com/NonFiction/Lowell/Mars/index.html .
Another is The Planet Mars: A History of Observation and Discovery by William Sheehan, The University of Arizona Press, Tucson at http://www.uapress.arizona.edu/onlinebks/mars/contents.htm This book is very good and full of information on early observations and observers as well and the latest probes.
I must admit that Mars still intrigues me in an imaginary way, beyond the bounds of hard scientific reality. I found this amazing passage in Lowell's Mars, Chapter 3...
"Meanwhile an interesting phenomenon occurred in the cap on June 7. On that morning, at about a quarter of six (or, more precisely, on June 8, 1h. 17m., G. M. T.), as I was watching the planet, I saw suddenly two points like stars flash out in the midst of the polar cap. Dazzlingly bright upon the duller white background of the snow, these stars shone for a few moments and then slowly disappeared. The seeing at the time was very good. It is at once evident what the other-world apparitions were,--not the fabled signal-lights of Martian folk, but the glint of ice-slopes flashing for a moment earthward as the rotation of the planet turned the slope to the proper angle; just as, in sailing by some glass-windowed house near set of sun, you shall for a moment or two catch a dazzling glint of glory from its panes, which then vanishes as it came. But though no intelligence lay behind the action of these lights, they were none the less startling for being Nature's own flash-lights across one hundred millions of miles of space. It had taken them nine minutes to make the journey; nine minutes before they reached Earth they had ceased to be on Mars, and, after their travel of one hundred millions of miles, found to note them but one watcher, alone on a hill-top with the dawn."
Wonderful stuff, the kind of thing that HG Wells must have read that inspired War of the Worlds or Edgar Rice Burroughs to write his Mars adventures. I guess I don't want to believe that Mars is a dead, cratered world, I want to believe in the living and wild world of Burroughs. But you have to be out at 4:00 AM and glued to the eyepiece to do that, when the rest of the tawdry world is asleep and bellicose warlords and beautiful Martian princesses reign over the red planet.
R.F. Royce
