The Herschel Objects and How to Observe Them (Astronomers' Observing Guides)
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Amateur astronomers – particularly deep-sky observers – are always on the lookout for new observing challenges. The Herschel Objects, and How to Observe Them offers the exciting opportunity of retracing the steps of the greatest visual observer and celestial explorer that ever lived. This is a practical guide to seeing the most impressive of Herschel’s star clusters, nebulae and galaxies. There has never been – and as of the time of submitting this proposal there still isn’t – an observer’s book devoted to the Herschel objects. The US-based Astronomical League has for several years sponsored a 'Herschel Club', reflecting the interest amateur astronomers have in this important but less widely known listing. The Herschel Objects, and How to Observe Them covers more than 600 of the brightest of the objects that Herschel saw, with detailed descriptions and images of 150 to 200 of the very best for viewing with amateur telescopes.
Stylized sketches of the Moon at low, medium, and high magnifications. While the image gets bigger at higher powers, less and less of it can be fitted within the eyepiece’s field of view. Observing Techniques It is generally recognized that the higher the magniﬁcation used on a telescope, the smaller the actual amount of the sky (or ﬁeld of view) that is seen. For this reason, it is standard procedure in sweeping for deep-sky wonders like those in the Herschel catalog (especially large star.
The bright encompassing nebulosity. This is one of the best objects of its class that Messier missed, being noticeably brighter than the famed Ring Nebula (M57) in Lyra. It is easily found less than 2°S of the star µ Hydrae, some 40° due S of the Sickle asterism in Leo, and is 3,300 light-years away. Showpieces of Class IV Hydra Monoceros H IV-2 (NGC 2261): 06 39 + 08 44, diffuse nebula, 10.0, 2¢ ¥ 1¢, = Caldwell 46/Hubble’s Variable Nebula. “Bright, very much extended 330°, nucleus cometic.
Ophiuchi, which is itself 2°NE of θ Ophiuchi. Generally regarded as a dim miniature of the Ring Nebula (M57) in Lyra, it is not only much smaller than its famous counterpart but much fainter. It can be seen in a 4-inch glass, and appears as a perfect little smoke ring at high power in 6- to 8-inch telescopes. A pale blue or green hue is also generally noticeable. Its extremely faint 15th-magnitude central star was not seen by Herschel and lies beyond the reach of all but the very largest amateur.
Together in the sky, the two objects are actually vastly far apart in space – the galaxy being some 5,000 times the distance of the cluster (10,000,000 light-years compared to 2,000 light-years). Talk about “extreme depth of ﬁeld” in the eyepiece! Note that Sir William did not mention about seeing these two objects together (which is really the big attraction here), the galaxy apparently lying outside the limited ﬁelds of view of his large telescopes (Fig. 8.3). Showpieces of Class VI Coma.
Observing list itself and requirements for being awarded a coveted Herschel Club Certiﬁcate, but also reading material about William Herschel and other related matters. It can be found at: http://astroleague.org/al/obsclubs/herschel/hers400.html. Since the formation of the original Club, the Rose City Astronomers in Portland, Oregon, has initiated a second Herschel Club list with an additional 400 targets – which the Astronomical League adopted as a Herschel II Club. (See its manual Observe: The.