Jasper Dark Sky Festival

Small-Scope Appreciation

You don’t need a big telescope to have big-time fun exploring the wonders of the night sky.


KHW and telescope

Ken and his little Newtonian reflector telescope. Courtesy Lynda Sawula

My handiest scope is a 4¼-inch Newtonian reflector that was assembled from homemade and commercial parts by telescope craftsman (and fellow SkyNews contributing editor) Gary Seronik. The heart of Gary’s one-off hybrid is an f/6 parabolic mirror he ground and polished himself. The two-foot optical-tube assembly rests on a bookshelf, its lightweight equatorial mount nearby. Both can be carried outside at a moment’s notice.

Although my suburban sky is significantly light-polluted, it occasionally features fairly steady atmospheric seeing. I live for those nights. During some hazy but tranquil evenings last March, I was able to run my little Newtonian up to 186× — a lot of magnification for a scope that size — and concentrate on what the sky conditions allowed: planets, double stars and the Moon.

Marius Hills on the Moon

The delicate, tiny Marius Hills on the Moon lie near the bright ray crater Kepler. Courtesy Gary Seronik

Our nearest celestial neighbour provided me with countless vistas worthy of high-power scrutiny. One that got me  outside  a  few  nights  before  full Moon was the area around the 40-kilometre-wide crater Marius, in Oceanus Procellarum, near the Moon’s west (left) limb. Marius hugs the Marius Hills, a concentration of small volcanic domes that my 4¼-inch gamely showed as lumpy terrain. My scope also picked up nearby Rima Marius, a sinuous line I could trace because the air was steady and the lighting was just right. North- ward, I inspected the brilliant crater Aristarchus,  slightly  smaller  Herodotus  and  the strangely  sculpted  depression  known  as Vallis Schröteri. What an incredible region!

And I doted on double stars. I began in Gemini with lustrous Castor, whose 1.9- and 3.0-magnitude sky-blue components, 4.2 arc seconds apart, were stunningly beautiful at 93×. For a pairing of similar separation but different colour, I turned to Leo and the deep yellow dots formed by 2.4-magnitude Algieba and its 3.6-magnitude companion. Porrima, in Virgo, challenged me with its pure white 3.5-magnitude twin suns 1.8 arc seconds apart. I needed 186x to  resolve this “headlight binary” cleanly. (The “headlights” are marginally wider now.) Another toughie, Izar in Boötes, sported a 2.6-magnitude orange primary and a 4.8-magnitude violet secondary separated by 2.9 arc seconds. Resolving that strongly uneven pair was tremendously satisfying.

Mars didn’t get very close last March, yet I identified the north polar cap, delta- shaped Syrtis Major and the elongated tandem of Sinus Sabaeus and Sinus Meridiani. Jupiter was sinking in the west, but my scope revealed the two main equatorial cloud belts and some narrow strips on either side. Following the four Galilean satellites was endless fun. Whenever a moon passed in front of Jupiter, I could follow its inky umbra across the banded disc — even the teensy one cast by Europa. Later, I turned to Saturn and its slowly opening ring system. Inside the rings, I glimpsed the two opposing threads of Cassini’s division plus the false “gap” between the rings and the  limb of the planet caused by Saturn’s shadow. Along with mega-moon Titan, I spotted four dimmer Saturnian satellites at one time or another.

All that with a 4¼-inch scope!

Its creator wasn’t surprised. “A lot of people dismiss such scopes as being of limited utility,” said Gary, “but your observations prove otherwise.” He might have been thinking of me, a lifelong fan of Dobsonian light-buckets, when he added: “One of the unintended consequences of inexpensive import Dobs is that more and more beginners start off with 8-inch and bigger scopes, without giving the little guys a chance.” Years ago, the telescopic rule of thumb was that cheap equals small. As a result, instruments like my no-frills Newt don’t get much respect. Pity, responded Gary: “Little scopes have an edge in portability, and they’re capable of wide fields of view that big scopes can’t touch.” So true! Early last March, I centred the Great Orion Nebula in my 4¼-inch and got the entire sword of Orion.

Those late-winter sessions with my Mighty Mouse Newtonian reminded me that small-scope astronomy can be a lot of fun, even in the cold. The joy is possible with any telescope—refractor, reflector, catadioptric — provided its optical and mechanical quality are high.

The bottom line is to get outside and see where your scope can take you.



Categories: Moon and Planets, Telescopes and Accessories
2 comments on “Small-Scope Appreciation
  1. Ken Lehan-Port says:

    I have a little Celestron, but I would like to move up abit more. What do you suggest in the 4″ – 8″ Newtonian-style ?
    Here in Ajax hard to find a light-free environment, so is tha to be considered when selecting a larger `scope ?
    Any comment welcome Thanks KLP

    • Gary says:

      Hi Ken:
      The advantages of a big scope are the same, regardless of light pollution. Have a look at our Astronomy Stores listing (in the Resources menu) to find a telescope shop near you, go in, and kick the tires on a few in person. I think you’ll find that will help you with your decision. And for more information on choosing telescopes, I can highly recommend the book, “The Backyard Astronomer’s Guide” by my SkyNews collegues Terrence Dickinson and Alan Dyer.

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