1/11/2024 0 Comments Telescope near meArtificial lighting makes using a telescope difficult, as the light can wash out faint stars. Light pollution: This term refers to any artificial lighting in your area at night. Objects viewed through a large focal length telescope look bigger than objects viewed through a small focal length. Such objects are either extremely far away or they emit very little light.įocal length: Focal length is another term that telescopes share with camera lenses. You often can swap out eyepieces on a telescope to obtain a greater or lesser level of magnification.įaint objects: Faint objects in the night sky are objects that are difficult to see, even with a telescope. This is an expensive hobby that requires particular pieces of equipment that are compatible.Įarth objects: When telescope makers say their models are good for viewing earth objects, they’re talking about birds or other far-off animals on earth.Įyepiece: The eyepiece is the portion of the telescope you peer through to see objects. The camera then photographs objects in the night sky. You mount your camera to the telescope, allowing the camera to “see” through the eyepiece. A large aperture allows more light to enter the lens, meaning you can better see faint objects in the night sky.Īstrophotography: Astrophotography is a hobby that combines telescope use with a digital camera. The aperture is the opening in the lens through which light travels. It celebrated its 200th anniversary in 2007.Aperture: In a telescope, the term aperture refers to the same thing as it does in a camera lens. The Portland Observatory is the only remaining historic maritime signal station in the United States. As an intact survivor from the Golden Age of Sail, the Observatory was added to the National Register of Historic Places in 1972, became a National Historic Landmark in 2006, and named a National Civil Engineering Landmark in 2006. The tower was saved and reopened in 2000. The City of Portland and concerned citizens collaborated with Greater Portland Landmarks to once again restore the Observatory. ![]() In 1984 Greater Portland Landmarks assumed management of the tower, opening it for regular tours. Then, ten years later, inspections revealed serious moisture damage and an infestation of powder-post beetles. ![]() Restorations were done and the tower opened to tourists in 1939. The Observatory fell into disrepair and was donated to the City of Portland. This signal tower communication greatly increased the efficiency of Portland Harbor and the Observatory remained a working marine signal tower run by the Moody family until 1923 when the invention of the two-way radio made it obsolete. Moody informed subscribing merchants by hoisting signal flags identifying their vessels. With his powerful telescope at the top of the tower, sea captain-turned-entrepreneur Moody could identify incoming vessels as far away as 30 miles. ![]() It was a commercial venture designed to give a competitive edge to ship owners who paid Moody a subscription fee of $5.00 a year to alert them when their ships were arriving.Īt the time, ships entering the harbor could not be seen from the docks of Portland until they rounded the point of land at Spring Point Ledge and were almost in the harbor. In 1807 Captain Lemuel Moody (1768-1846), ordered construction of this octagonal, 86-foot high tower on Munjoy Hill to serve as a communication station for Portland’s bustling harbor.
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