Variable star Algol rises in the northeast in the early evening.
The November 21 – 23 weekend is a great one for watching Algol wink. Also known as Beta (β) Persei (as well as the Demon Star), this variable star changes from magnitude 2.1 to 3.4 and back again, over a period of just under 69 hours. That might not sound like much, but it equates to a 3½× brightness change.
The Newtonian reflector is one of the most versatile optical configurations ever created. Whether homebuilt or commercially manufactured, a good Newtonian can rival the performance of any optical design.
Knowledge is power. The more you know about your Newtonian reflector’s potential and its pitfalls, the better equipped you’ll be to ensure it’s delivering peak performance.
Who was Clavius, and why is one of the biggest craters on the Moon named after him? Not surprisingly, the answer to that question has a tangled history. In my regular On The Moon column, I delve into the lunar name game to illuminate the mysteries of lunar nomenclature.
For more about what’s in the current issue, visit SkyNews.ca
Open cluster NGC7789 is located in western Cassiopeia.
Rather than simply chase down the obvious Messier objects (as fine as so many of them are), sometimes it's nice to stretch out a bit and try for some less famous targets. One of my autumn favourites is open cluster NGC7789, located in Cassiopeia.
Considering it's the celestial "King," the constellation Cepheus doesn't get a lot of attention from binocular observers. But, there are a pair of stellar jewels located along its southern reaches: Delta and Mu Cephei, the subjects of this issue's Binocular Highlights column.
Telescopes can be funny beasts. I've long thought it remarkable how certain designs persist in spite of having obvious (and at times, frustrating) shortcomings. The collimation setup found on most telescopes qualifies. My Telescope Workshop column this month features a far superior X-Y alignment mechanism made by Australian ATM, Doug Parkes.
For optimum performance, precisely aligned optics are a must. Luckily, achieving this goal doesn't have to be difficult.
Most telescope users know that the only way to get every last drop of performance from a reflector telescope is to ensure that the optics are in good collimation. Here's a method that's simple and doesn't require tools or even a centre-dotted primary mirror.
Me, the Outback Travelscope, and a bloody big rock. (Photo courtesy George Brandie)
When I was preparing to travel to Australia for a total solar eclipse and some dark-sky observing sessions in the Outback, I decided it was finally time to rebuild my 8-inch travelscope so that it could go into my suitcase and arrive safely at my destination.
Binocular stargazing is full of surprises. Sometimes you stumble across a pretty cluster and wonder how you’d previously missed it. Other times, you hunt and hunt for a galaxy listed at 8th magnitude, only to come up empty handed. It’s enough to make you wonder — what makes one object a binocular standout and another difficult challenge? Compiled here are the five most important factors that determine whether or not a deep-sky wonder will turn out to be binocular trash or treasure.
Magnificent Comet Hale-Bopp on April 3, 1997. It is unquestionably one of the finest comets of the past two decades, but is it the best one of all?
Few celestial objects excite the imaginations of stargazers and the general public like a good comet. The recent apparition of Comet ISON prompted me to reflect on the all the comets I've been fortunate enough to see in the past 20 years. There have been some stunners, some surprises, and a few that could have been great, but fell short. Here’s my (highly subjective) pick of the five most interesting and spectacular comets from the past two decades.
I built my 12.75-inch Dob for less than $700 — much less than a comparable commercially made scope would have cost. But is making your own scope always a money saving proposition? That's what inquireing minds (canine or otherwise) want to know.
For diehard ATMs, building telescopes is a way of life. But for others, the decision about whether or not to make a scope often hinges on economics. Will I save money building my own? The question shows up regularly in on-line forums and in my e-mail box. Before the emergence of a large-scale commercial telescope industry, the answer was a definite “yes!” But with the current abundance of low-cost, imported Dobs, and the increasing expense (and scarcity) of telescope-making supplies, it’s reasonable to wonder if it’s still possible to save a few bucks by going the home-made route. The prevailing conventional wisdom says “no,” but my own experiences suggest the answer isn’t as cut and dried as that.
Requiring only a few parts, this simple and effective setup provides stable images for detailed views of the night sky.
“This is the best binocular mount I’ve ever used!”
Those were the first words out of my mouth as I came indoors from testing my just-completed binocular rig. It’s rare that I build something that actually works better than expected, but finally I’d come up with a binocular mount that provides steady views, is easy to use, very portable, and simple to build. It was a good night.
I’ve been building and using telescopes for more than three decades and I’ll share with you a secret: collimating a Newtonian reflector is easy. So why does it seem so difficult when you’re just starting out? Probably because you’ve done your homework by Googling the subject and have read and re-read everything you’ve found. And now, you’re lost in a forest of information — some of it contradictory, some of it densely technical. Truly, sometimes less is more.
This image of the Scorpius Milky Way was captured from Costa Rica with a DSLR camera and the simple hinge tracker mount described here.
If you have a DSLR camera and are interested in astronomy, you’ve probably considered dipping a toe into the astrophotography waters. But a camera is only part of the equation — for exposures longer than a few seconds, a tracking mount is usually necessary. Unfortunately, most suitable mounts are relatively bulky, or expensive, or both. But not the hinge tracker. It costs less than $10 to build, takes less than an evening to assemble, and requires no batteries. And best of all, you can put one together even if you’ve never built anything more complicated than Ikea furniture.
I invite everyone to check out my web site, FilmAdvance.com.
In addition to astronomy, photography is a big passion of mine. So, I started FilmAdvance.com as an outlet for my photographic explorations. There will inevitably by some astronomy related content posted there, but mostly it’s about seeing the universe through the lens of a camera, instead of the eyepiece of a telescope. Look in on it from time to time to see what I've been up to with my cameras and darkroom. Enjoy!
Combining optical excellence with rock-steady views, Canon's image-stabilized binoculars are a stargazer's dream come true. But is one best for you?
For a long time, 7×50 or 10×50 binoculars were considered the best choice for stargazing. Such binos are relatively lightweight, inexpensive, and capable of delivering fine wide-field views of the heavens. But most people find that hand-held 10×50s represents the upper limit of the weight and magnification comfort zone. Models featuring higher magnification or more aperture require a tripod or dedicated binocular mount for steady views. Even 10×50s rarely work near their potential without support. Unfortunately, such devices ensure that an instrument much loved for its portability and convenience becomes encumbered with as much paraphernalia as a small telescope. Enter the image-stabilized binocular.
Attention to detail is what separates a regular Newtonian reflector from one optimized for high-contrast performance. This 6-inch f/9 uses every trick in the ATM’s book to deliver superb planetary and deep-sky views.
This was the first telescope I made using my own optics. Like most telescope makers, I got started the easy way, by building Dobsonians with mirrors ground by others. But one day I got bit with the mirror-making bug. I blame my friend Lance Olkovick, our local club’s mirror-making ace. But why a long-focus 6-inch? At the time I was a hardcore Jupiter junkie and was convinced that a long-focus Newtonian would deliver excellent views of my favourite subject. I also wanted to prove a point.
The old saying that less is more rings true for telescope magnification, but there are many factors to consider before choosing your ultimate wide-field eyepiece.
Low-magnification views of the night sky can be breathtaking. It’s only with low power that we can fully appreciate the splendor of the Pleiades, the foggy expanse of the Andromeda Galaxy, or the wispy filaments of the Veil Nebula. But if discussions on internet forums are anything to go by, there's a lot of confusion out there about how magnification, field of view, and exit pupils relate to each other. And without understanding these factors, you might end up shortchanging your telescope’s low-power capabilities.
What you need to know when it comes to optimizing your scope’s thermal behavior.
Generations of backyard astronomers have debated why, inch-for-inch, the performance of a high quality refractor usually edges out an equal-quality Newtonian reflector. This disparity is most apparent when viewing low-contrast planetary detail — the images in a good refractors often have a touch more snap to them. Is there some intrinsic shortcoming in the design of the Newtonian reflector that makes this inevitable?
This simple, easy-to-build mount provides the perfect introduction to long-exposure astrophotography.
Round stars. That’s the difference between astrophotos captured with a camera that tracks the sky’s motion versus one that doesn’t. Traditionally you’d make a tracked photo by placing your camera piggyback on a telescope with a motorized equatorial mount. But that’s a lot of equipment to deal with if all you want are some nice-looking constellation portraits or a shot of a newly discovered comet — especially if you have to travel to reach your favorite dark-sky destination.