My handiest scope is a 4¼-inch Newtonian reflector that was assembled from homemade and commercial parts by telescope craftsman (and SkyNews 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 hazy but tranquil evenings I’m able 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.
Our nearest celestial neighbour provides 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. Northward, I inspected the brilliant crater Aristarchus, slightly smaller Herodotus and the strangely sculpted depression known as Vallis Schröteri. What an incredible region!
And I dote on double stars. One spring evening 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 186× 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.
Planets are another prime target–especially Mars and Jupiter. Even when the red planet isn’t at its best, I can identify numerous features including the polar caps, delta- shaped Syrtis Major and the elongated tandem of Sinus Sabaeus and Sinus Meridiani. On Jupiter, my scope reveals the Great Red Spot along with the two main equatorial cloud belts and some narrow strips on either side. Following the four Galilean satellites is endless fun. Whenever a moon passed in front of Jupiter, I can follow its inky umbra across the banded disc—even the teensy one cast by Europa. And let’s not forget Saturn and its magnificent ring system. Inside the rings, I can glimpse 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’ve spotted four dimmer Saturnian satellites at one time or another.
All that with a 4¼-inch scope!
Its creator isn’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! I’m able to enjoy the Great Orion Nebula in my 4¼-inch along with the entire sword of Orion.
Observing sessions with my Mighty Mouse Newtonian remind me that small-scope astronomy can be a lot of fun. 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.