Space Walk Among the Stars - Introduction
When you are ready, Select a Space Walk
This is a series of audio guides, with accompanying charts, that I created back in 2008 to help beginners learn the joy of starhopping - finding objects in a telescope without the aid of go-to or other electronic means of punching in objects through an electronic interface. You download the mp3 audio guide and listen while you are at the eyepiece of your telescope, and it guides you through space to find the featured objects. It's that simple!
Beginners may often purchase a 6, 8, or 10 inch dobsonian telescope, or other non-computerized telescope as their first deep sky viewing tool. These bare bones telescope variants require you to learn the sky using star charts or a charting app and hop from a starting point, usually a bright star, by matching the view in the telescope finderscope or low power eyepiece to the chart to find a dim object that you can't see with the finderscope's limited power. This is called starhopping. It's becoming a lost art, but it's not hard to do with a little help. Enter Space Walk Among the Stars.
I created these audio guides to help you learn how to starhop, and also to give you some information about what you are seeing as you take these journeys. Each episode is about 30 minutes long, and provides cues at various points to pause the recording to take in the view and then continue when you are ready. I have tried to provide some information about these fascinating celestial objects. The information is from 2008, so I apologize if some of it is outdated, but generally this should still hold true. Please let me know if I need to issue any corrections, but remember different sources often report different information such as distances, sizes, etc.
How to use these starhopping guides
These Space Walks are tailored for those in the Northern Hemisphere and in temperate latitudes, but can often be seen from other locations.
First, find a Space Walk Among the Stars episode that you can use now. Not all objects are visible throughout the year. A great online charting app is Stellarium. Click to allow it to know your location, search for one of the objects in the Space Walk that you want to use, using it's designation such as M42, or common name, "Orion Nebula," and make sure it is currently visible. An info box should pop up with information tailored to your location. It will tell you its visibility (rise/set times or visible all night). Also, check the info above that for "Az/Alt." That's the position in the sky- right to left (Azimuth) and up and down (Altitude). Look for the altitude, the second number listed, and ideally it will be +30 degrees or higher if possible, higher if you have obstructions from your observing location. Any lower than that is doable, but you get into more haze and light glow and your observations won't be as pleasing. The higher in the sky, the less atmosphere you have to look though and often the less light pollution you have to deal with, i.e., skyglow on the horizon from nearby cities or towns.
Second, review the charts that go with that particular Space Walk to familiarize yourself a little with the area before you try to find it in the telescope. That will also help you follow along if you get lost or confused, which is going to happen sometimes.
Third, click on the link to the mp3 audio file and download it to your cell phone, tablet, or whatever you will be using to listen to it. I recommend wireless ear buds in the field so it's easier to hear, easier to pause, and you don't disturb others, but use your own judgment based on your situation.
Fourth, once you are set up at your observing site, be it at home or a remote site, get comfortable, dress very warmly if it's at all cold out, and make sure you have a clear sky and you're away from lights and light glow as much as possible. A red led flashlight such as the Rigel Systems 2-LED red or mini helps you move around and find things in your observing space in the dark without ruining your night vision. Or modify a white neck light and keep your hands free! Avoid white light, which is much more damaging to your dark adaptation.
Fifth, align your finderscope with the main view in your eyepiece and you are ready to go. Here's how:
Aligning your telescope so you can find things
I cover this briefly in each episode, but at the start of any observing session you want to make sure your finderscope, or finder, the little telescope mounted on the main one, is lined up with what you are seeing in the eyepiece- that removable lens you use to view and change powers. You can do this roughly during the day by aiming at something like the top of a telephone pole. At night, choose one of the brightest stars that you won't mistake for a different one.
Start by aiming the telescope the best you can by sighting along the tube. Put your lowest power eyepiece in the telescope. That will give you the widest field of view. With eyepieces, the higher the mm number, the lower the power. So if you have a 20mm eyepiece and a 10mm eyepiece, use the lower power 20mm eyepiece. Slowly move the telescope manually around the area until you have that bright star or your target in the field of view (FOV). Center it. Then look through the finderscope. If it's somewhere in the finderscope's FOV, then you just turn the little screws on the side of the finderscope— there are usually two or three—until you have moved it into the center of the crosshairs, red circle, or under the red dot. Check again that the object is still in the center of your main telescope's eyepiece. If not, center it again, and then tweak the finderscope so that the object is in the center of both your finderscope and your eyepiece.
You can get even more precise by putting a higher power (lower number) eyepiece in and tweaking the finderscope screws, but low power will get you close enough.
Essentially what you've done here—finding the object first in the main view and then in the finderscope—is the opposite of what you'll be doing when observing. When you are observing, you will be finding the object first in the finderscope and then looking in the eyepiece. If you've aligned the finderscope properly and have the object in its crosshairs, you should then see the object in the middle of your eyepiece FOV. Some finderscopes hold their setting better than others, but it's always good practice to adjust the alignment at the beginning of every observing session, as it can get bumped out of alignment. It's frustrating when you can't find things and finally realize your finderscope was not in alignment!
Managing expectations
You've seen spectacular images of the universe from the James Webb and Hubble Space Telescopes and other sources, maybe friends of yours who do astro-imaging, and you bought a telescope hoping you would see something similar. Unfortunately, you won't. Our eyes only see in the visible light wavelengths and they don't collect photons and build them up like an imaging system does. The larger telescopes also have much larger mirrors and collect much more light than a backyard telescope can, yielding much brighter and more detailed views.
Except for the Moon, brighter planets, brighter stars, and a few deep sky objects, especially brighter planetary nebulae which often show blue or green, you will see most objects as white or gray. Don't worry, you will still see spectacular sights. They just won't look like the images you've seen. Your huge advantage is that you are seeing the actual objects yourself, the photons that travelled sometimes millions of light years to register in your eye. Many of them are quite beautiful in a small telescope, and all of them are awesome when you understand what they are. Many are very faint and difficult to see even if you have them centered in your field of view. With practice and patience you will get better at finding them and seeing them better.
Here are just a few tips to help you see better:
- Find the darkest location you can observe safely and legally in. If you observe from your backyard, try to block any lights with buildings, trees, or other obstructions.
- Pick a night when it's expected to be clear- free of clouds and heavy haze or smoke.
- Let your eyes adapt to the dark for at least 20 minutes or so before observing.
- Use a red LED light if you need light.
- Dress comfortably. Overdress for chilly weather. You won't enjoy it if you're freezing.
- When looking at faint objects in the eyepiece, look slightly away from them. This is called averted vision. This uses the rods in your eyes, rather than the cones. The rods see faint things better. Move your eye around to find the sweet spots where really dim objects show up better. They may only be visible in little glimpses, maybe even just 10 percent of the time, but keep trying and you'll spot them again, building up an image in your mind, just a like an imaging chip.
- Breathe. Take breaks. Relax. Occasionally look up at the stars or for meteors or satellites. Trace out the constellations. Then go back to the telescope.
And now you are ready to enjoy the cosmos with your telescope. Relax, have fun, and CONNECT WITH THE UNIVERSE!
A little note about my own observing
For many years I found everything by starhopping. These days I can't crane my neck to look through a straight-through finderscope any more, so I have modified both my telescopes to use an azimuth circle built into the base to find the horizontal direction of an object, and a digital angle gauge, commonly used in a workshop, to find the altitude (up and down) direction of the same object. These altitude-azimuth coordinates are provided by apps such as Sky Safari Pro, which I recommend and use, when you select an object to view.
You look up the coordinates, rotate the scope base so the pointer is on the correct azimuth, for example, 270.0 if it is due west, and tilt your scope up to the altitude reading, for example 45.0 degrees, or halfway up to the zenith, reading it off the gauge that's mounted magnetically or stuck on your telescope tube. If you've lined up the base on a bright star or the Moon, you should be pretty close to the correct position.
You still need to match the field you are looking at with the star chart, so even then starhopping is a valuable skill. And it's really enjoyable and satisfying when—boom! —you find what you are looking for. See this lengthy thread on Cloudy Nights, the premier amateur astronomy forum, for more information on this project that you might someday want to pursue: Degree Circles
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