All articles starting with O
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Orinoco Guiana Shield
Orinoco Guiana Shield, FEOW freshwater ecoregion 308, is the clear- and blackwater upland half of the Orinoco basin in Venezuela, drained by the Ventuari, Caura, and Caroní, with tepuis to 2800 m, 49 endemic fishes, and mercury-releasing gold mining as its main threat.
Orinoco High Andes
Orinoco High Andes, FEOW freshwater ecoregion 305, montane freshwaters in the Colombian and Venezuelan Andes draining to the Orinoco; headwaters of the Guaviare, Meta, Arauca, and Apure rivers, six endemic fishes, highest point Sierra Nevada del Cocuy at 5493 m.
Orinoco Llanos
Orinoco Llanos (Llanos del Orinoco), tropical savanna floodplains of Venezuela and Colombia in the Orinoco Basin; second-largest Neotropical savanna over 500,000 km2, seasonally flooded, with 60 endemic fish species and only 5% protected.
Orinoco Piedmont
Orinoco Piedmont, FEOW freshwater ecoregion 306, a montane transition between the Orinoco High Andes and Llanos in Colombia and Venezuela; upper Guaviare, Meta, Arauca, Apure rivers; nine endemic fish species; threatened by deforestation and oil.
Orio Palmer
Orio Joseph Palmer (1956-2001) was an FDNY battalion chief who climbed to the 78th floor South Tower impact zone on 9/11, radioing conditions; his recovered 2005-released transmissions revealed the highest FDNY ascent that day.
Oriol Cardona
Oriol Cardona Coll, Spanish ski mountaineering (skimo) sprinter from Banyoles; 2023 and 2025 world sprint champion; won the first Olympic men's skimo sprint gold and mixed relay bronze at Milano-Cortina 2026, Spain's first Winter gold since 1972.
Oriol Pich
Oriol Pich (born 1992) is a Spanish computational biologist at the Francis Crick Institute known for first-author papers on mutational footprints of cancer therapies and tumor-infiltrating clonal hematopoiesis.
Oriol Romeu
Oriol Romeu, Spanish defensive midfielder (born 1991, Ulldecona), La Masia product; Chelsea, Southampton (256 games), Girona, Barcelona 2023–25; Champions League winner; now Avispa Fukuoka-bound.
Oriol Vinyals
Oriol Vinyals is a Spanish machine learning researcher known for sequence-to-sequence learning and leading AlphaStar, and a former Google DeepMind VP who co-founded Discovery Loop in 2026.
Oriole Park at Camden Yards
Oriole Park at Camden Yards, the Baltimore Orioles' MLB ballpark since April 6, 1992, built by the Maryland Stadium Authority with HOK on the B&O rail yards; the retro-design template with the B&O Warehouse, Eutaw Street, 45,971 capacity, and a 30-year lease signed in 2023.
Oriolus
Oriolus is the Linnaean 1766 genus of Old World orioles in the family Oriolidae, spanning Africa, Eurasia, and Australasia; its type species is the Eurasian Golden Oriole Oriolus oriolus, a Least Concern migrant, distinct from unrelated American icterid orioles.
Oriolus oriolus
Oriolus oriolus, the Eurasian golden oriole (also common golden oriole, pirol), a Palearctic-migrating Oriolidae passerine breeding in Europe and wintering in Africa; only Old World oriole breeding in temperate Northern Hemisphere; IUCN Least Concern.
Orion
Orion, known as "the Hunter", is a constellation straddling the celestial equator, one of 88 recognized by the International Astronomical Union and containing the Orion Nebula.
Orion (character)
Orion (DC Comics) is a Jack Kirby-created New God, son of Darkseid raised on New Genesis, first appearing in New Gods #1 (1971); the Dog of War starred in Walt Simonson's Orion (2000-2002) and recent Ram V and Ngozi Ukazu series.
Orion (constellation)
Orion is one of the 88 officially recognized constellations, straddling the celestial equator and containing Betelgeuse, Rigel, the Belt, and the Orion Nebula, the nearest large star-forming region.
Orion (spacecraft)
Orion is NASA's deep-space crewed spacecraft, built by Lockheed Martin, carrying four astronauts to the Moon on Artemis missions; its first crewed flight, Artemis II, flew around the Moon in 2026.
Orion (Ὠρίων) (mythology)
Orion (Ὠρίων) was a giant hunter of Greek mythology whom Zeus placed among the stars after his death, forming the constellation that still bears his name.
Orion A
Orion A is a giant molecular cloud in Orion about 1,300 light-years away, the nearest site of massive star formation and host of the Orion Nebula.
Orion and the Dark
Orion and the Dark is a 2024 DreamWorks/Netflix animated film directed by Sean Charmatz, written by Charlie Kaufman from Emma Yarlett's picture book, starring Jacob Tremblay and Paul Walter Hauser, released February 2, 2024.
Orion Arm
The Orion Arm, also called the Local Arm or Orion spur, is the spiral arm of the Milky Way containing the Sun, lying between the Sagittarius and Perseus arms.
Orion B
Orion B is a giant molecular cloud in Orion, about 400 parsecs away, forming the northern half of the Orion Molecular Cloud Complex and hosting the Horsehead and Flame Nebulae.
Orion Bar
The Orion Bar is a bright edge-on ionization front and photodissociation region in the Orion Nebula, where ultraviolet light from the star θ¹ Orionis C strikes the molecular cloud.
Orion correlation theory
The Orion correlation theory, proposed by Robert Bauval in 1989 and popularized in The Orion Mystery (1994), claims the Giza pyramids reproduce Orion's Belt stars; Egyptologists reject it.
Orion D. Weiner
Orion D. Weiner is a cell biology professor at UCSF's Cardiovascular Research Institute who studies how cells control shape and movement, showing that membrane tension organizes cell polarity.
Orion Energy Credit
Orion Energy Credit is the fund family of Orion Energy Partners, a New York private credit firm founded in 2015, renamed Orion Infrastructure Capital in 2022.
Orion European Real Estate Fund Series
Orion European Real Estate Fund Series is a series of Luxembourg-domiciled European real estate funds managed by Orion Capital Managers, a London private equity firm founded in 1999.
Orion I
Orion I, also called Orion Source I or source I, is a compact radio source in the Orion Kleinmann-Low nebula, likely a massive protostar surrounded by an edge-on ionized disk.
Orion KL
Orion KL, the Kleinmann–Low nebula, is the brightest far-infrared region of the Orion Molecular Cloud 1 and the nearest high-mass star-forming environment, discovered in 1967 by Kleinmann and Low.
Orion Mine Finance
Orion Mine Finance, now branded Orion Resource Partners, is a New York-based private capital manager for mining, founded by Oskar Lewnowski in 2013 and managing over $9 billion in assets.
Orion molecular cloud complex
The Orion molecular cloud complex, also called the Orion complex, is a vast cloud of gas, dust, and young stars in Orion, the nearest region of ongoing star formation.