![]() The 14 mm ED eyepieces funneled enough photons to clearly separate the bright nebulosity around the Trapezium (opens in new tab) star cluster from the sisterhood of hot stars clustered around the binary, or double-star system 42 Orionis the region sometimes called the " Running Man Nebula (opens in new tab)." But, given the NYC sky glow, I couldn't quite resolve the four brightest stars in the heart of the Trapezium nebula itself, whose dancing motions suggest they orbit a black hole (opens in new tab) of perhaps 150 solar masses - at 1,300 light-years, it is comparatively close to us. (Image credit: the Orion constellation (opens in new tab) hanging behind the light-polluted haze of New York City, I poked around the busy stellar metropolis between NGC 1977 (also known as Sharpless 279) and Messier 42 (M42, or the Orion Nebula (opens in new tab)) in the so-called " sword of Orion (opens in new tab)." The complex metropolis of stars, dust and glowing gas in the region of the "Sword of Orion" makes an excellent target for binocular astronomy. With two eyes - and therefore both brain hemispheres - engaged in active observing through these fast, color-fringe free, wide-field optics, you can feel completely enveloped in the universe "lost in space" with your feet still comfortably on terra firma. The Oberwerk BT-82-XL-ED (opens in new tab) strikes an agreeable balance between day vs. Oberwerk has hacked that cost down by more than two-thirds moreover, they've made a much more graceful product. To step up to low-dispersion "ED" glass with a fully apochromatic light path that does not add these color artifacts used to carry a price tag of more than $7,500 if you could find them at all. These tend to be more expensive than the new Oberwerk XLs, but not as optically good because they are "achromatic," you would notice annoying false-color fringes around bright objects. So, angled eyepieces - and the ability to adjust the distance between them - began to appear, under brand names like Vixen (opens in new tab), Nikon (opens in new tab) and Newcon. Looking straight up at the sky through big binoculars is cumbersome. Focusing takes work, and image contrast is not very high galaxies look like gray smudges. ![]() These were (and are) inexpensive ($250 to $450), but inconvenient (no angled eyepieces), and tend to be difficult to align to both your eyes. Next came a clutch of up-sized "handhelds on steroids" from hobbyist telescope manufacturers such as Orion (opens in new tab), Celestron (opens in new tab), Barska and Levenhuk. Blocky and heavy, they were designed with opposing armies in mind, not amateur astronomers. The first ones to appear in the consumer market were military surplus in the early 1990s. Big binocular telescopes, optically "fast" enough to be capable of astronomy, have traditionally been expensive and heavy. ![]()
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