08Feb2012

Mike Roy, a scientific instrument maker at Caltech, shows his backyard Astro-Mar Observatory he built with a 12″ Newtonian telescope at his home in the San Gabriel Valley, USA (Sarah Reingewirtz/Staff Photographer )

So you just got a shiny new telescope for Christmas? But what you see through it doesn’t look anything like the pictures on the box? Well, before you throw your hands up in frustration, there are a few things you should  know.

I would wager that nearly every astronomer, professional or amateur, male or female, was first inspired and excited by astronomy with a small telescope similar to yours. Begin by first erasing from your mind any idea you may have that what you will see in your telescope is going to come close to those wonderful images taken by the Hubble Space Telescope. Grandma and Grandpa are generous people and love you dearly, but you didn’t really believe a multi-billion dollar space telescope would actually fit in such a small box, now did you?

Hubble telescope image known as Pillars of Cre...

Star forming pillars in the Eagle Nebula. Thjis is Hubble’s view. Image via Wikipedia

Those beautiful pictures are only meant to inspire your sense of curiosity, to temp you to reach far and discover new wonders. Pretend that you never read the marketing claim on the box that your telescope has a “magnification of 525x”. Instead, let me tell you what is really capable of this incredibly simple little device made of lenses and mirrors.

If your new telescope has lenses made of glass rather than just clear plastic you should know that your “refractor” type telescope, is far superior to the one that Galileo, often called the father of modern astronomy, first used more than 400 years ago. If your telescope has a concave mirror at its heart instead of a lens, it is of the “reflector” type or “Newtonian” telescope named for its inventor Sir Isaac Newton.

Now stop to consider just some of what these two men accomplished in astronomy over their lifetimes in helping us to better understand our universe and that none of it happened easily or overnight. In the excitement of opening your telescope box you may have skipped some important step in the instructions and eagerly jumped ahead to look at your first astronomical object instead. Go back and carefully check each step again.

One thing that is often overlooked with any new telescope is aligning the small sighting “finderscope” with the “big” telescope. In the daytime, find a distant stationary object like a telephone pole. Sight along the telescope tube until you locate the pole and crossbar in the center of the eyepiece. Now adjust the finderscope (using the adjustment screws) until it too has the pole centered.

It has a pair of “crosshairs” like a rifle scope that makes this easier. If there are no adjustment screws, try placing a few thicknesses of paper under the bracket which holds it until both telescope and finderscope are aligned with each other. Be sure all the screws are snug, but don’t get carried away.

Important! Astronomy requires a certain degree of investment of time and effort. It asks that you be inspired by the journey of discovery and become involved. If you are to begin any trip, you will need a good map to know where you are going. When exploring the heavens, you also need a sort of “map” of the night sky only it’s called a “star chart”. Magazines like Astronomy and Sky and Telescope, along with interesting astronomy articles, have easy-to-use monthly star charts. An excellent pocket guide with lots of information on each constellation is “Stars” by Ian Ridpath (Harper Collins, $8). I’ve had mine for many years; it fits easily in a pants or jacket pocket.

Taking a first step toward exploration of the night sky and using just your eyes, go outside and with your star chart in hand learn some of the major constellations so that you can begin to “navigate” the sky. There’s no need to memorize them, just become familiar with the location of some of the brightest stars as they will become your signposts. Try to find a dark corner in your backyard away from street and security lights. Free skymaps go to www.skymaps.com and visit Sydney Observatory for maps and audio.

The central vision of the human eye works well in most of our surroundings where we are used to looking directly at something. But we have to train our brain to use a different part of the eye when viewing the dim stars, galaxies or nebulas at night.

Our eyes take some time to get used to the darkness. When leaving a brightly lit house, let your eyes get used to the dark for 20 or 30 minutes. Soon you will be able to see much dimmer stars than you could when first going outside.

One thing often overlooked with any new telescope is aligning the small sighting “finderscope” with the “big” telescope.

Don’t look directly at a dim object, but slightly to one side instead. Astronomers call it using your “averted vision”. There is a very distant object called the Blinking Eye Nebula that demonstrates the value of averted vision. If you look in the general area of the object you will see it, but when you are tempted to look directly at it for a better view, it disappears! Look away again and it reappears! Astronomy can be fun, but nobody said it would be easy!

Viewing through a telescope is not called looking, or glancing, but “observing”. Spend some time studying the object you are viewing. Details are usually very faint. When attending public star parties, I encourage all of my guests to take their time at the eyepiece and not rush away. Looking for seconds will only be a glimpse, while minutes spent will result in observing amazing details you might have otherwise missed.

Most of astronomy involves attempting to view faint objects at unbelievably enormous distances. Even close neighbors like the other planets are still tens or hundreds of millions of miles away. Some stars, though much larger than our own sun, are so distant they will always appear as mere specks even in the largest telescopes.

If your telescope came with more than one eyepiece, begin your observing by selecting the one with the lowest magnification. That’s the one with the largest number marked on its side like “25mm Plossl“. The main purpose of your telescope is to gather much more light than your eye alone. Magnifying that image is really secondary. The practical maximum magnification for a small telescope observing the moon and planets is closer to 200x and often even less. It’s better to see an object small, but with clarity, than a large image that is out of focus.

Try locating something bright and easy to find with your telescope at first. The moon makes a great starting point and the “seas”, craters, volcanos, and valleys look absolutely wonderful! See if you can locate the Sea of Tranquility where the first men from Earth walked on the moon. After that, try a planet or two.

Through February, face westward shortly after sunset and look rather high almost directly overhead. The bright “star” that doesn’t twinkle, is Jupiter, the largest planet in our solar system. Now observe Jupiter with your telescope and with any luck, you will also see a few small “stars” right near by. Galileo, with his small telescope, was the first to realize that these four “stars” were actually moons of Jupiter.

Now turn toward the west. That object even brighter than Jupiter is the planet Venus. Watch it  get brighter through this month. Observe it slowly go through phases just like our moon does.

Visit the Great Orion Nebula,(In the handle of the Saucepan) an enormous gas cloud in the constellation, Orion, the hunter, where stars are actually being born. It is so distant that its light has traveled for 1,500 years just to reach your telescope and is easily visible with even inexpensive binoculars. It is the finest object in the sky, the favorite of many and easily visible from winter through springtime.

With astronomy, as in life, remember to aim high and reach far. For even if you should miss the moon, you will be sure to land among the stars! Attend a public star party-just ask me and I’ll try and locate one for you. Source: Pasadena Star News

Morris Adams says:

These are some useful tips. I like the second paragraph. Thanks.