NGC 6853 M27 The Dumbbell Nebula

Dumbbell Routines and Exercises

Dumbbell Exercises and Lifting Routines

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With or without a narrowband filter, the Dumbbell Nebula makes its presence known immediately, even in our compromised skies. This is not one of those sights that you suspect you can see! It appears as a bright white egg-shape in the field of view, quite luminous and striking (Figure 7.55). Sufficient aperture will resolve its famous outline easily, and shadings of brightness become obvious. The subtle extensions on either side may be seen with larger scopes, and give the nebula a somewhat different overall outline, much more elongated (as in my drawing in Figure 7.55a). The illuminating star is a hard catch, though in good viewing conditions, you may possibly succeed. It just shows on the video frame (Figure 7.55b) at the center of the "bar". An image intensifier works in an interesting way; the nebula fades substantially, but many stars within and around it, unseen without intensification, become obvious to the point that perceptions of the internal structure of the nebula itself seem to be influenced by the stellar outlines (Figure 7.55). This, of course, adds a new degree of visual understanding. As a deep sky sight, it is another "sure thing" for visitors, as one of the few celestial objects that they may actually have heard of and can see so clearly.

Figure 7.55. NGC

6853 (M27): a drawing: narrowband filter. The disparity between the visual and video images is affected by the eye's different sensitivities to frequencies of light, opposed to that of image intensifiers and video cameras. Although viewing the nebula will probably be to greatest effect with a narrowband filter, I believe the appearance and general outline of the central "bar" is even affected by ambient light from the linear arrangement of the stars, those essentially unseen when viewing with a light filter but clearly showing in the video image. b Video frame: intensifier (look carefully!).

NGC 6960/6992 The Veil Nebula

One of the most celebrated nebulae, the Veil Nebula used to be one that routinely disappointed its would-be viewers. Thanks to the magic of light filters, it has become something of an almost easy mark on good nights, even with the sky conditions that form the focus of this book. The two NGC numbers refer to the two primary parts of the nebula, on each side of the area it covers (Figures 7.56 and 7.57). (A third component of the "Veil" is far less prominent, and a more central part of it, but it is unlikely to be detectable.)

Certainly this whole interstellar gas structure reveals evidence of being the result of some gigantic cosmic explosion many thousands of years ago. A narrowband

Figure 7.56.

NGC 6992: narrowband filter.

filter will likely aid greatly in revealing a sight much like well-known portraits, although significantly less bright. Don't expect to see color, however; its hue is the pale white/gray characteristic of most live deep space viewing. Depending on your scope's aperture, though, you may well be surprised with just how much of it you can clearly resolve, with much delicacy of the "filamentary" features revealed. Image intensification will not be successful with the "Veil", even though the light is of the emission variety; the specific wavelengths and total brightness make all the difference.

Figure 7.57.

NGC 6960: narrowband filter.

Figure 7.56.

NGC 6992: narrowband filter.

Figure 7.57.

NGC 6960: narrowband filter.

NGC 7008

This curious, rather faint little planetary nebula occupies a place on this list because it seems almost unique with its heart-shaped form (Figure 7.58). Careful examination may also reveal some mottling. Do not expect to be dazzled by its presence, however, and it will not respond favorably to image intensification. For whatever reason, I cannot help being led back to it for another look.

NGC 7009 The Saturn Nebula

Named the Saturn Nebula by Lord Rosse, this planetary probably first revealed its true nature to this nineteenth-century figure with his newly constructed 72-inch reflector. Fine CCD or observatory views will at once make the reason for its name clear, as it has on each side the most extraordinary projecting ansae (Figure 7.59). These give the nebula a very Saturn-like appearance. From our unfavorable vantage point, however, the extremities of these are likely to remain unseen under the best of conditions and with the largest amateur scopes. I have, on occasion, seen hints of these extremities, particularly by moving the object in the field of view to allow indirect vision to reveal their presence. The rest of the object is a splendid sight regardless, with the central star, two surrounding ovals and projecting irregularities prominently displayed for us under intensification. It is interesting to note that

Figure 7.59.

NGC 7009: a video frame: intensifier; b drawing: intensifier.

Rosse's great telescope was probably unable to reveal the central star or the darker central region, both quite easy with image intensification and a quarter the aperture of his great instrument.

Figure 7.59.

NGC 7009: a video frame: intensifier; b drawing: intensifier.

NGC 7027

This tiny planetary is well worth the trouble to seek out and study, even from our suburban locations. It appears as a bright star-like core with two illuminated lobes on one side (Figure 7.60). Faint extensions to these lobes are also just visible. You will also see narrow separations between all three of these main components. It is necessary to utilize higher magnifications to see it well, and certainly you will need them to discern any detail, because it is so diminutive. The video image here was produced with a Barlow lens, as with many of the other smaller and brighter subjects, and shows NGC 7027 approximating the way it appears with powers between 200x and 300x.

NGC 7078 (M15)

Truly one of the jewels of the skies, M15 is a relatively compact globular, and slightly oblate in shape (Figure 7.61). Through the intensified eyepiece, this oblate shape is visually quite noticeable in the shape of the core, a tightly knit mass ablaze with stellar points. Also within this area, there are some dark lanes that

Figure 7.60.

NGC 7027: a video frame: intensifier; b drawing: intensifier.

show quite readily. The cluster is notable for its great concentration of stars.

M2 is another of the more notable globulars, bright but small only because of its great distance. This makes its stellar population much fainter and densely packed than is the case with the closer clusters. Like M15, it is somewhat oblate in appearance, and under intensified viewing it reveals a wonderful, evenly distributed compact array of fine, bright star points (Figure 7.62). It is unusually well revealed in my Collins unit, and in many ways more magically than most globulars. Near the northwest corner is a prominent dark lane, which shows well on the video image, and it can easily be seen under good conditions with image intensification. Of all the globular star clusters, M2 is amongst the most satisfying and beautiful to view.

NGC 7662

One of the brighter and more striking planetaries, NGC 7662 will always remind me of the great E.E. Barnard, who drew it so impressively at the beginning of the twentieth century, with the great Lick Observatory 36-inch refractor. Seen under intensification in significantly less apertures, it reveals much the same

sight that Barnard saw, with the central star being an easy mark within the very well-defined annulus, even though this star is a blue dwarf (Figure 7.63). What appears casually like a double ring is not so much unusual as it is beautifully formed and detailed. The nebula is noticeably oval in shape, with a flattening on one of the longer sides.

This, then, completes our survey of the most successfully viewed objects from our suburban environs, based on my own perspective and viewing experiences. With all that conspires against us, it is surprising to me just how many sights there are in suburbia that are still so accessible and rewarding in so many ways. Happily, in Chapter 8 you will find that the possibilities go on, and many of the sights listed there may even find their way onto your own preferred list.

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Getting Started With Dumbbells

Getting Started With Dumbbells

The use of dumbbells gives you a much more comprehensive strengthening effect because the workout engages your stabilizer muscles, in addition to the muscle you may be pin-pointing. Without all of the belts and artificial stabilizers of a machine, you also engage your core muscles, which are your body's natural stabilizers.

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