Frederick William Herschel was a German-British astronomer and composer. He frequently collaborated with his younger sister and fellow astronomer Caroline Herschel. Born in the Electorate of Hanover, William Herschel followed his father into the military band of Hanover, before emigrating to Britain in 1757 at the age of nineteen.
Yerkes Observatory is an astronomical observatory located in Williams Bay, Wisconsin, United States. The observatory was operated by the University of Chicago Department of Astronomy and Astrophysics from its founding in 1897 until 2018. Ownership was transferred to the non-profit Yerkes Future Foundation (YFF) in May 2020, which began millions of dollars of restoration and renovation of the historic building and grounds. Yerkes re-opened for public tours and programming in May 2022. The April 2024 issue of National Geographic magazine featured a story about the Observatory and ongoing work to restore it to relevance for astronomy, public science engagement and exploring big ideas through art, science, culture and landscape. The observatory offers tickets to programs and tours on its website.
The history of the telescope can be traced to before the invention of the earliest known telescope, which appeared in 1608 in the Netherlands, when a patent was submitted by Hans Lippershey, an eyeglass maker. Although Lippershey did not receive his patent, news of the invention soon spread across Europe. The design of these early refracting telescopes consisted of a convex objective lens and a concave eyepiece. Galileo improved on this design the following year and applied it to astronomy. In 1611, Johannes Kepler described how a far more useful telescope could be made with a convex objective lens and a convex eyepiece lens. By 1655, astronomers such as Christiaan Huygens were building powerful but unwieldy Keplerian telescopes with compound eyepieces.
Speculum metal is a mixture of around two-thirds copper and one-third tin, making a white brittle alloy that can be polished to make a highly reflective surface. It was used historically to make different kinds of mirrors from personal grooming aids to optical devices until it was replaced by more modern materials such as metal-coated glass mirrors.
The Dominion Astrophysical Observatory, located on Observatory Hill, in Saanich, British Columbia, was completed in 1918 by the Canadian government. The Dominion architect responsible for the building was Edgar Lewis Horwood. The main instrument is the 72-inch-aperture (1.83 m) Plaskett telescope, proposed and designed by John S. Plaskett in 1910 with the support of the International Union for Cooperation in Solar Research.
Siding Spring Observatory near Coonabarabran, New South Wales, Australia, part of the Research School of Astronomy & Astrophysics (RSAA) at the Australian National University (ANU), incorporates the Anglo-Australian Telescope along with a collection of other telescopes owned by the Australian National University, the University of New South Wales, and other institutions. The observatory is situated 1,165 metres (3,822 ft) above sea level in the Warrumbungle National Park on Mount Woorat, also known as Siding Spring Mountain. Siding Spring Observatory is owned by the Australian National University (ANU) and is part of the Mount Stromlo and Siding Spring Observatories research school.
Mount Stromlo Observatory located in the west of Canberra, Australia, is part of the Research School of Astronomy and Astrophysics at the Australian National University (ANU). Australia's oldest telescope and several others at the observatory were destroyed by bushfire in 2003.
Hamburg Observatory is an astronomical observatory located in the Bergedorf borough of the city of Hamburg in northern Germany. It is owned and operated by the University of Hamburg, Germany since 1968, although it was founded in 1825 by the City of Hamburg and moved to its present location in 1912. It has operated telescopes at Bergedorf, at two previous locations in Hamburg, at other observatories around the world, and it has also supported space missions.
Melbourne Observatory is an observatory located on a hill adjacent to the Royal Botanic Gardens Victoria. The observatory commenced operations in 1863 and was decommissioned from official Government work in 1945. The observatory has since continued as an astronomical observatory and remains open to the public. Melbourne Observatory is also permanently on the Australian National Heritage List under 'Melbourne's Domain Parkland and Memorial Precinct' since early 2018.
Grubb Parsons was a historic manufacturer of telescopes, active in the 19th and 20th centuries. They built numerous large research telescopes, including several that were the largest in the world of their type.
The Crossley telescope is a 36-inch (910 mm) reflecting telescope located at Lick Observatory in the U.S. state of California. It was used between 1895 and 2010, and was donated to the observatory by Edward Crossley, its namesake.
William Herschel's 40-foot telescope, also known as the Great Forty-Foot telescope, was a reflecting telescope constructed between 1785 and 1789 at Observatory House in Slough, England. It used a 48-inch (120 cm) diameter primary mirror with a 40-foot-long (12 m) focal length. It was the largest telescope in the world for 50 years. It may have been used to discover Enceladus and Mimas, the 6th and 7th moons of Saturn. It was dismantled in 1840 by Herschel's son John Herschel due to safety concerns; today the original mirror and a 10-foot (3.0 m) section of the tube remain.
Great refractor refers to a large telescope with a lens, usually the largest refractor at an observatory with an equatorial mount. The preeminence and success of this style in observational astronomy defines an era in modern telescopy in the 19th and early 20th century. Great refractors were large refracting telescopes using achromatic lenses. They were often the largest in the world, or largest in a region. Despite typical designs having smaller apertures than reflectors, great refractors offered a number of advantages and were popular for astronomy. It was also popular to exhibit large refractors at international exhibits, and examples of this include the Trophy Telescope at the 1851 Great Exhibition, and the Yerkes Great Refractor at the 1893 World's Fair in Chicago.
Sidney Charles Bartholemew "Ben" Gascoigne was a New Zealand-born optical astronomer and expert in photometry who played a leading role in the design and commissioning of Australia's largest optical telescope, the Anglo-Australian Telescope, which for a time was one of the world's most important astronomical facilities. Born in Napier, New Zealand, Gascoigne trained in Auckland and at the University of Bristol, before moving to Australia during World War II to work at the Commonwealth Solar Observatory at Mount Stromlo in Canberra. He became skillful in the design and manufacture of optical devices such as telescope elements.
The Astronomical Society of Victoria (ASV) is an amateur astronomy club in the state of Victoria, Australia. It was founded in 1922, making it one of the oldest such clubs in the country, and with some 1500 members it claims to be one of the largest amateur astronomy organisations in the southern hemisphere. Membership is open to all with an interest in astronomy, and the society caters for people with a wide range of ages, backgrounds, abilities and interests.
The Linden Observatory Complex is a heritage-listed former observatory and manufacture of optical precision implements and now residence, museum, observatory, education facility and meeting venue located at 91 – 111 Glossop Road, Linden, City of Blue Mountains, New South Wales, Australia. It was designed and built by Ken Beames from 1938 to 1948. It is also known as K Beames Engineering Co. The property is owned by the Linden Observatory Trust. It was added to the New South Wales State Heritage Register on 5 March 2010.
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