he·​lio·​stat | \ ˈhē-lē-ə-ˌstat How to pronounce heliostat (audio) \

Definition of heliostat

: an instrument consisting of a mirror mounted on an axis moved by clockwork by which a sunbeam is steadily reflected in one direction

Examples of heliostat in a Sentence

Recent Examples on the Web Placing three heliostats, spaced every 120 degrees along a crater rim would ensure steady illumination to the mine, and two more would beam light at the vapor capture tent and fuel processing plant, according to Sowers. Joe Pappalardo, Popular Mechanics, "Digging Up Regolith: Why Mining the Moon Seems More Possible Than Ever," 27 Apr. 2020 But those peak around 1,000 degrees, because each heliostat has to be individually calibrated and can fall out of alignment over time. Laura Mallonee, Wired, "Automated Solar Arrays Could Help Incinerate Global Warming," 21 Jan. 2020 The researchers found that for a solar plant with a central tower, the efficiency of the heliostats closest to the tower was higher. Shweta Narayan, Smithsonian, "How Engineers of New Energy Technology Are Taking Cues From Nature," 31 Aug. 2019 The plant, operated by Torresol Energy, consists of 2,650 heliostats — mirrors that turn to track the motion of the sun, fanning out around, and reflecting sunlight toward, a 150-meter (490-foot)-high tower. Shweta Narayan, Smithsonian, "How Engineers of New Energy Technology Are Taking Cues From Nature," 31 Aug. 2019 Molten Salt Thermal Storage Molten salt can retain heat for a long time, so it's generally found in solar thermal plants, where dozens or hundreds of heliostats (large mirrors) use the heat from sunlight to create energy. Megan Geuss, Ars Technica, "Here are humanity’s best ideas on how to store energy," 28 Oct. 2017 The facility consists of an array of heliostats—or panels that reflect sunlight onto a thermal tower—and a molten salt tank. Megan Geuss, Ars Technica, "Pumping liquid metal at 1,400°C opens the door for better solar thermal systems," 13 Oct. 2017 The observatory connects to a heliostat mounted outside, which tracks the sun and reflects light at the telescopes. Nicholas St. Fleur, The Seattle Times, "College town in Illinois gets ready for its moment under no sun," 14 July 2017 Gary Poliquin of Lake Zurich was another astronomical society member who set up a simple heliostat, which bounced the image through a lens and then onto a large screen about 40 feet away. Frank S. Abderholden, Lake County News-Sun, "'A bite out of the sun': Eclipse causes a buzz at Volo Bog," 21 Aug. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'heliostat.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of heliostat

1747, in the meaning defined above

History and Etymology for heliostat

New Latin heliostata, from heli- entry 1 + Greek -statēs -stat

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Time Traveler for heliostat

Time Traveler

The first known use of heliostat was in 1747

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Cite this Entry

“Heliostat.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/heliostat. Accessed 17 Apr. 2021.

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Britannica.com: Encyclopedia article about heliostat

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