Bringing the Universe to Your Classroom!

Showing posts with label visual observing. Show all posts
Showing posts with label visual observing. Show all posts

Wednesday, May 22, 2019

The O-TEAM: A Thousand and One Nights

(Late - very, very late; one night in 1989...)

As one-third of that, one-time, infamous trio of hard-core, dedicated, 'back-woods', 'MacGyver'-ish, observational astronomers: the 'O-Team' - Mike Petrasko, Muir Evenden, and myself, who's late-night and, sometimes, 'deep-freeze' telescopic adventures, back around 1989 (typically, in below-freezing temps) -- I would never, ever have believed that one day - our telescopes would be able to, practically, "take us by the hand", and give us a detailed, orated tour of the night sky - all by their artificially intelligent selves. Nope - that's the kind of thing that only happened in sci-fi films...

Moreover, how could any of us possibly have imagined, that, variable stars - those, peculiar stellar anomalies who are light-output, vary over periods of time, from about a few hours to several days, should turn out to be *variable* - because there were planets getting in the way! - by crossing the faces of those stars (as seen from our perspective)...of all things!!

Telescopes used by the O-Team on The Woods Hole Golf Course - Illustration by Dale Alan Bryant.
Telescopes used by the O-Team on The Woods Hole Golf Course - Illustration by Dale Alan Bryant.

Many times, over the "O-Team years", some 30-something years ago, I had made painstaking efforts at trying to capture such things, as, the North America nebula, or the galactic core in Sagittarius, on film, using a piggy-backed, 35mm SLR, loaded with Fujichrome 200, acetate slide-film. With a lot of patience, and, even more, practice, something like this could be gotten - in as short a span as 45 minutes - using the telescope, as a guide scope, during the exposure. I could never have imagined (not even in any of my wilder dreams) that, film - the conventional platform for photography, since its invention - the century, before last - would soon be replaced with the microchip capable of generating an equivalent image in 10-20 seconds - un-guided!!

Unfortunately: I have missed out - entirely - on the GOTO, computerized, Dobsonian-mounted telescope revolution: that is - the kind of amateur astronomical telescopes that are capable of re-positioning themselves, by 'slewing' across the sky, via, computer-controlled, stepped servo-motors - to any celestial object in the heavens, using the celestial coordinates, right-ascension, and declination - by converting them into their alt-azimuth counterparts - all on command!"....

I've never used one. In fact - I've never even SEEN one (at least, not 'in person').

No. My active days (or rather, nights) as an observational astronomer with the O-Team were the kind, where, in the cold months, you got dressed for the weather using three layers of outer garments, three layers of warm socks for your feet - wrapped over, with plastic trash bags to keep the warmth in under your boots - and, at least, one wool cap and a pair of mittens (mittens hold in heat better than gloves).

If you didn't look like you were ready to start training attack-dogs - you were missing some clothing.

When you were finally ready - you disassembled your scope and packed it into the back seat, trunk, or bed of your vehicle, and - if you could, still, just slide into the front seat - you were ready to drive yourself, along with your gear, to one of your, very, best-kept secrets: a chosen, dark, secluded and, preferably, isolated observing site! (We actually had two sites that we frequented, but, one, in particular, was, by far, our preferred nocturnal "delinquency". You see: on many, many starry nights, you could find me, and my telescope (well - and, my truck!), and Mike and Muir, and their vehicles, perched on one of the fairways at the Woods Hole Country Club's plush, green carpet, of highly-manicured grass. To say that we were obsessed - well, that would be a really, really accurate statement...

On any, given, clear night, we would abandon the warm, blissful comfort of our cozy beds at around 12:00 midnight, and drive out to our, apparently, God-given observing station; or any party-cloudy night, for that matter - just in case. And if you've never seen the unlikely, ominous sight of a silhouetted Volvo, parked in the middle of a golf course in the middle of the night - before, well, you just haven't lived!

From our perspective, golf courses were built, and designed, for astronomers. They offer wide expanses of sky, and - serendipitously - are covered with a durable, and, surprisingly well-kept swath of grass - which, seems to run on, in all directions, forever! Now, what philanthropic soul had done this great service for science? (I never did believe in the rumors, that, they also used these green havens, for other, unimportant 'sporting activities', as well).

Here's how it usually went...

After arriving at the golf course, and, having driven, up, onto the fairway, you set up your scope and connected it, via, mini-jumper cables w/alligator-clips, to your vehicle's battery. This was to run the electro-mechanical clock-drives, that, slowly moved the scope, in synch with Earth's rotation, across the sky to follow the particular celestial object you were observing. Muir used an 8-inch Celestron Schmidt-Cassegrain. Mike had an Edmund Scientific, 4.25-inch AstroScan, and I used an 8-inch Meade Newtonian reflector.

The next step was to set up the card table and lay everything out on it: a very good, laminated star atlas with reticle templates, a red-filtered, military-style elbow flashlight, eyepieces w/case, pocket shortwave radio, tuned to WWV (for timing anything you wanted to time) along with, Mrs. Holmes' home-made brownies, if you were fortunate enough - and pray that you didn't completely drain your vehicle's battery, by dawn. (There were actually statements, like: "Oh, well; if my battery dies, I'll just call a tow-truck in the morning.", made, frequently...who cared?!)

Now, all this was usually set up near the frozen, ice-covered, first-hole putting-green of the WHGC - regardless of winter, or its threat of frostbite, or - of the threat of getting booted off the course by the local law enforcement. You see, we once (once?!) had a brief encounter with a police officer, who, was out on his rounds and, spotting, three, parked automobiles - in the middle of a golf course - had decided to drop by our private, highly-manicured observatory.

Having noted our three, rather large-ish, optical instruments, tables, chairs, ladders, and vehicles - electrical connections and all - the officer, slowly and cautiously approach our bunker, and asked, "What kinds of weapons", we were using to, obviously, protect ourselves against, the potential, horrors of the night sky. Naturally, we all-too-excitedly broke into a rather lengthy discourse about the myriad wonders - galaxies, nebulosities, etc., that we had seen that night, and offered him a view for himself; with such fervor and passion (which, he, apparently didn't share with us), that, he probably just couldn't wait to escape the bizarre situation.

Over time, they eventually learned to ignore us, entirely and, for the most part, we continued to have the WHGC, all to ourselves for our continuing, awesome onslaught of the universe, at large.

And that's how those days went.

But times have changed dramatically. Today, all this is done, remotely, with a laptop, or tablet, or even, smartphone - right from the comfort of your own bed!!

What will the next, 30-something years in amateur astronomy bring?.....

Dale Alan Bryant
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Sunday, May 1, 2016

Winging It!

Much observational astronomy is done with an itinerary in mind; be it sketches of deep-sky objects, planets, the moon, comets, etc., with time allotted for each object. Along with fellow astronomers, Mike Petrasko and Muir Evenden, I used to do galaxy scans of a number of galaxies, in search of extragalactic supernovae events, or, stellar explosions in other galaxies. This kind of observing requires a conventional star atlas and special galaxy charts at one’s side, along with an array of oculars, a red acetate-covered flashlight, Astro-goggles (dark-adaptation goggles) paper, pencils and such.

Amateur Astronomer Observing
Amateur Astronomer Observing.

But this kind of observing session is for more advanced amateurs, not something the beginning astronomer is looking at any time soon. And that’s alright. There are other ways of doing it. If you’re new to astronomy and have only recently acquired your first telescope - regardless of size - take it out into the backyard and set it up, otherwise equipment-less, if that should be the case (it would be nice to have some kind of atlas with you, for reference, and to save a little time, but it isn’t absolutely necessary).

Point your marvellous instrument toward the sky and just start scanning - randomly. In no time, you’ll be coming across all kinds of things. Look at each, take a mental note and move on. Spend an hour or two, just randomly aiming the telescope, or, do a more cohesive sweep of the sky, somewhat overlapping the field of view of the scope on each pass. Just enjoy the various objects that pop into view, make a mental note and continue.

When you’ve had enough of this, pack it up and go to bed. I guarantee you'll lie there, in bed, that night, running the various sights you’ve seen, over and over in your head. You’ll wonder what it was that had that tail-like thing sticking out of it, what gave that other smudge of light its unusual shape, color, etc.

A few observing sessions like this, and you’ll want to do more, know more and acquire more in no time. This is how it all started for me, with a 60mm Tasco® refractor telescope on a simple mount, at age 19, all those ages ago.

By Dale Alan Bryant
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Monday, April 25, 2016

Observing Double and Multiple Stars

There have been occasional clear nights when I was inspired to do some serious visual observing, however, whatever chance I had of getting a decent night of observing it was going to be hindered by the brightness of the full moon. Back a few years ago, on one particular crystal clear night during a full moon, I dragged out my Edmund Scientific Astroscan 4.25" reflecting telescope and determined exactly what I could observe.

As I looked up and pondered at what I could view on such a bright night, a thought suddenly struck me. I realized I have never taken the time to seriously observe double and multiple star systems. Being that deep-sky observing was not an option, I figured why not take a shot at splitting some of the well known double and multiple stars? A small telescope-like my 4.5" reflector can resolve many double and multiple star systems. These star systems are interesting to observe because they offer different orientations from one another; star colors, various magnitudes as well as separations between component stars.

Artist's Rendition of Double Star System Albireo in Cygnus
Artist's Rendition of Double Star System Albireo in Cygnus.

Due to the almost endless selections of these star systems and the fact that the availability of these specimens can be seen on almost any night of the year makes this type of observing possible on a bright night with small telescopes. Some double stars are known as "fixed" double stars meaning their components have not moved since their discovery. However, the majority of these star systems do show orbital motion over periods of time. The explanation is that the secondary star appears at a different position as it orbits the primary star. Some stars show orbital motion over a span of years while others may take decades to change their relative positions.

Double star observers use a unit of measurement called a position angle. Determining position angles of double stars is a project that any amateur astronomer or student could undertake with any size telescope. The position angle measured between the two stars is from 0 to 360 degrees in an easterly direction from the north. The difficult part of determining position angles is knowing exactly what orientation your telescope's field is. For example, a reflecting telescope has a field of view south at the top and east is to the right. An easy way to remember position angles for this field is to picture an imaginary clock face with the primary star at the center...

North (0°) is at 6 o'clock, East (90°) at 3 o'clock, South (180°) at 12 O'clock, and West (270°) at 9 o'clock. For example, the position angle for the double Albireo, a double star in the constellation Cygnus the swan is 55° with a separation of 34.6".

An article posted on Sky and Telescope Magazine's website has a list of the best double stars to observe as well as more information on observing double stars.
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