Nebulae and How to Observe Them

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A Fun Night Under the Stars 26 As we got to the site we realized this was going to be a great night. There were no clouds in the sky, and as we set up the scopes lots of other observers arrived. By twilight there were 22 vehicles and plenty of scopes and observers to soak up the starlight. We had a great weekend and we rated the transparency of the first night as 10 out of 10: as good as it gets. The Saturday night was 8 out of 10, still excellent. The Milky Way was wide and bright. I used my 100mm (4 inch) RFT refractor to go after dark nebulae in Scorpius and Ophiuchus. We did several things that made a big difference: we dressed warm. It was 100 degrees F (41 degrees C) when we left Phoenix on the desert floor; by 2 AM it was 28 deg F (−4 degrees C). I promise that is cold to a bunch of desert dwellers. So having all the cold-weather gear was important. Also we had done our homework; we had found a good site and created observing lists so we were ready to go when the weather was good on a new moon weekend. Some of this is luck (the weather), some was preparation on our part. We did leave out one thing – insects. There are little flesh-eating bugs in that meadow and I, along with others, wound up with little red bite marks on our ankles. So next year we will stock up on insect repellant before leaving. One more thing to add to the list. It never ends. Be Prepared.
Chapter 5 Improving your Skills As this is called the “Advanced Observer” series of books, I believe that my readers are willing to spent some time and effort acquiring the skills needed to become an avid deep sky observer. So here are some things that you need to know to become a skilled observer. Getting and Staying Dark-Adapted The human eye is a marvelous detector of light. During the day, it sees amazing detail in objects far and near. Once night falls, the eye and brain work together to provide the opportunity for your eye to see quite a lot in surroundings that are approximately 10,000 times fainter than full daylight. That is assuming the Moon is below the horizon. During a day when you are planning to observe that evening, wear sunglasses when outside. It seems to me that the dazzle of bright daylight makes your eye take extra time to get fully dark-adapted. You don’t have to “do” anything to have this physical and chemical reaction start to happen. You do have to protect it once you are dark-adapted. A single burst of white light can mean that it will take 30 minutes or so for your eye to return to its previous level of adaptation. So don’t turn on the lights unless it is an emergency and don’t go out observing with people who don’t have good discipline about white light. It is easy – use dim red torches, turn off the door-activated lights in your car and make certain that the other observers around you do the same. Again, I said a dim red flashlight; I put some masking tape over the front of my flashlight to make certain that it provides a faint, diffuse light. I recommend it. A.J. and I have found that a dark cloth over your head while at the eyepiece allows you to see to a deeper limiting magnitude. I also see more detail within the object I am observing when I am using the “monk’s hood.” I have a black cloth, A.J. uses a dark towel, but either way it makes you concentrate on the field of view and also blocks off external light, even at a dark site. Learning to Really Observe You have spent all this time, money and energy to get out under dark skies and provide yourself a good telescope and a dark-adapted eye. So don’t just glance at that presentation of the marvelous Universe that is in the field of view. Spend some time really observing that nebula, cluster or galaxy. Use high and low power to get Improving your Skills 27
Page 2 and 3: Astronomers’ Observing Guides
Page 4 and 5: Steven Coe Phoenix, AZ 85022 Stevec
Page 6 and 7: Contents Acknowledgments . . . . .
Page 8 and 9: Sagittarius Nebulosity . . . . . .
Page 10 and 11: Viewing the Sky 2 First is ease of
Page 12 and 13: Viewing the Sky 4 My large telescop
Page 14 and 15: Viewing the Sky 6 Those two telesco
Page 16 and 17: Viewing the Sky 8 • Ghost images
Page 18 and 19: Viewing the Sky 10 Along with eyepi
Page 20 and 21: Viewing the Sky 12 Fredericksen, an
Page 22 and 23: Becoming a Deep Sky Observer 14 Cha
Page 24 and 25: Becoming a Deep Sky Observer 16 Jim
Page 26 and 27: Becoming a Deep Sky Observer 18 era
Page 28 and 29: Using a Computer 20 Chapter 3 Using
Page 30 and 31: Using a Computer 22 Web Sites It is
Page 32 and 33: A Fun Night Under the Stars 24 Afte
Page 36 and 37: Improving your Skills 28 the comple
Page 38 and 39: Improving your Skills 30 Knowing th
Page 40 and 41: Nebula Knowledge 32 Chapter 6 Nebul
Page 42 and 43: Nebula Knowledge 34 and a small, ho
Page 44 and 45: Nebula Knowledge 36 than iron deman
Page 46 and 47: Nebula Knowledge 38 that there are
Page 48 and 49: Nebula Knowledge 40 from the outer
Page 50 and 51: Northern Autumn Nebulae 42 Chapter
Page 52 and 53: Northern Autumn Nebulae 44 Here is
Page 54 and 55: Northern Autumn Nebulae 46 This ima
Page 56 and 57: Northern Autumn Nebulae 48 This ima
Page 58 and 59: Northern Autumn Nebulae 50 Image of
Page 60 and 61: Northern Autumn Nebulae 52 Grus Neb
Page 62 and 63: Northern Autumn Nebulae 54 This is
Page 64 and 65: Northern Autumn Nebulae 56 NGC 1624
Page 66 and 67: Northern Winter Nebulae 58 Chapter
Page 68 and 69: Northern Winter Nebulae 60 IC 2149
Page 70 and 71: Northern Winter Nebulae 62 This ima
Page 72 and 73: Northern Winter Nebulae 64 discover
Page 74 and 75: Northern Winter Nebulae 66 This ima
Page 76 and 77: Northern Winter Nebulae 68 IC 443 S
Page 78 and 79: Northern Winter Nebulae 70 Monocero
Page 80 and 81: Northern Winter Nebulae 72 NGC 2261
Page 82 and 83: Northern Winter Nebulae 74 the sky
Page 84 and 85:
Northern Winter Nebulae 76 This ima
Page 86 and 87:
Page 88 and 89:
Page 90 and 91:
Northern Winter Nebulae 82 M 45 CL+
Page 92 and 93:
Northern Winter Nebulae 84 NGC 3132
Page 94 and 95:
Northern Spring Nebulae 86 Chapter
Page 96 and 97:
Northern Spring Nebulae 88 Using th
Page 98 and 99:
Northern Spring Nebulae 90 tary neb
Page 100 and 101:
Northern Spring Nebulae 92 they cou
Page 102 and 103:
Northern Spring Nebulae 94 lished a
Page 104 and 105:
Northern Spring Nebulae 96 This dar
Page 106 and 107:
Northern Spring Nebulae 98 With A.J
Page 108 and 109:
Northern Summer Nebulae 100 This im
Page 110 and 111:
Northern Summer Nebulae 102 Ara Neb
Page 112 and 113:
Northern Summer Nebulae 104 IC 1396
Page 114 and 115:
Northern Summer Nebulae 106 Cygnus
Page 116 and 117:
Page 118 and 119:
Northern Summer Nebulae 110 With th
Page 120 and 121:
Northern Summer Nebulae 112 Ophiuch
Page 122 and 123:
Page 124 and 125:
Page 126 and 127:
Northern Summer Nebulae 118 area is
Page 128 and 129:
Northern Summer Nebulae 120 Vulpecu
Page 130 and 131:
Nebulae are Just the Start 122 Chap
Page 132 and 133:
124 Appendix Object Other Type Con
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Index Abell 21 69 Abell 31 61 Abell
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Nebulae and How to Observe Them

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