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Myopia, also known as near-sightedness and short-sightedness,[5] is an eye disease[6][7][8] where light from distant objects focuses in front of, instead of on, the retina.[1][2][7] As a result, distant objects appear blurry while close objects appear normal.[1] Other symptoms may include headaches and eye strain.[1][9] Severe myopia is ...
A telescope in the Very Large Telescope system producing four orange laser guide stars A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation.The word laser is an anacronym that originated as an acronym for light amplification by stimulated emission of radiation.
Lidar ( / ˈlaɪdɑːr /, also LIDAR, LiDAR or LADAR, an acronym of "light detection and ranging" [1] or "laser imaging, detection, and ranging" [2]) is a method for determining ranges by targeting an object or a surface with a laser and measuring the time for the reflected light to return to the receiver.
Below are two tables which report the average adult human height by country or geographical region. With regard to the first table, original studies and sources should be consulted for details on methodology and the exact populations measured, surveyed, or considered. With regard to the second table, these estimated figures for adult human ...
Mount Kilimanjaro from space, illustrating its diverse vegetation zones. [3] Mount Kilimanjaro ( / ˌkɪlɪmənˈdʒɑːroʊ /) [4] is a dormant volcano located in Kilimanjaro Region of Tanzania. It has three volcanic cones: Kibo, Mawenzi, and Shira.
The 91-foot (28 m)-tall lighthouse on South Stack was designed by Daniel Alexander and the main light is visible to passing vessels for 24 nmi (44 km; 28 mi), and was designed to allow safe passage for ships on the treacherous Dublin – Holyhead – Liverpool sea route. It provides the first beacon along the northern coast of Anglesey for east ...
The Starry Night (Dutch: De sterrennacht) is an oil-on-canvas painting by the Dutch Post-Impressionist painter Vincent van Gogh painted in June 1889. It depicts the view from the east-facing window of his asylum room at Saint-Rémy-de-Provence, just before sunrise, with the addition of an imaginary village.[1][2][3] It has been in the ...
