42,772 articles
History of watches
The history of watches begins in Italy around 1500 with small spring-driven clocks, evolving through the pocket watch into the wristwatch, which dominated production worldwide by the 1930s.
History of weather forecasting
The history of weather forecasting runs from local proverbs and barometers to telegraph weather maps, the Bergen school's 1921 polar-front theory, and numerical prediction on electronic computers from 1950.
History of weather observation
The history of weather observation traces how regular, comparable measurement of atmospheric conditions grew from manuscript records into instrument networks, telegraph-based forecasting, and internationally standardized national weather services.
Histosols
Histosols, commonly called bogs, moors, peats, or mucks, are soils formed in thick deposits of decaying plant material with no permafrost, one of the twelve USDA soil orders.
Hitoshi Miyasaka
Hitoshi Miyasaka (宮坂 等) is a Japanese materials chemist and professor at Tohoku University's Institute for Materials Research, known for gas-responsive porous magnets and chiral hybrid perovskites.
Hitoshi Nozaki
Hitoshi Nozaki (野崎 一, 1922–2019) was a Japanese organic chemist and Kyoto University professor whose laboratory developed the Nozaki–Hiyama–Kishi reaction and pioneering asymmetric cyclopropanation work.
HITRAN
HITRAN, the high-resolution transmission molecular absorption database, compiles spectroscopic parameters that computer codes use to simulate light transmission and emission in gases, especially atmospheric ones.
Hitting time
In mathematics and physics, a hitting time, or first-passage time, is the first time a stochastic process reaches a specified state or crosses a threshold.
Hiyama coupling
The Hiyama coupling is a palladium-catalyzed cross-coupling that forms a carbon–carbon bond between an organosilane and an organic halide, reported by Hatanaka and Hiyama in 1988.
Hjalmar Mellin
Hjalmar Mellin, full name Robert Hjalmar Mellin, was a Finnish mathematician (1854–1933) who gave the Mellin transform its first systematic formulation and applied it to the Riemann zeta function.
HKUST-1
HKUST-1, also known as MOF-199, is a porous copper-based metal-organic framework first reported in 1999 by researchers at the Hong Kong University of Science and Technology.
HL Tau
HL Tau (HL Tauri) is a young, still-forming T Tauri star about 450 light-years from Earth in the constellation Taurus, with one of the most studied protoplanetary disks known.
HLA (time signal)
HLA is the call sign of the standard time and frequency radio station run by KRISS in Daejeon, South Korea, broadcasting Korea Standard Time on 5 MHz since 1984.
HM Sge
HM Sge (HM Sagittae) is a symbiotic nova in the constellation Sagitta, about 3,400 light-years away, whose 1975 outburst brightened it 250-fold and never faded.
HMPL-760
HMPL-760 is HUTCHMED's investigational third-generation, non-covalent, reversible BTK inhibitor targeting wild-type and C481S-mutated BTK, now in a registrational Phase III DLBCL trial (NCT07409428) with R-GemOx in China.
HMS Dolphin (1751)
HMS Dolphin was a 24-gun Royal Navy frigate, built in 1751, and the first ship known to sail around the world twice, under Byron and Wallis.
HMS Endeavour
HMS Endeavour, originally the Earl of Pembroke, was a British collier sailed by James Cook from 1768 to 1771 for scientific discovery, later serving as the transport Lord Sandwich.
HMS Erebus (1826)
HMS Erebus was a Royal Navy bomb vessel, launched in 1826, that carried James Clark Ross to Antarctica and was lost with Franklin's 1845 Northwest Passage expedition.
HMS Protector (A173)
HMS Protector is the Royal Navy's only icebreaker and ice patrol ship, a Norwegian vessel commissioned in 2013 that surveys Antarctic waters, supports research stations, and reached farther north than any Royal Navy ship in 2021.
HN Peg
HN Peg (HD 206860) is a nearby, magnetically active G-type star in Pegasus, 59 light-years away, with a directly imaged brown dwarf companion, HN Peg B.
Ho Nyung Lee
Ho Nyung Lee is a condensed matter physicist at Oak Ridge National Laboratory known for atomic-scale synthesis of complex oxide thin films and a 2006 PECASE award.
Ho‐kwang Mao
Ho-kwang Mao (毛河光) is a Chinese-American high-pressure geophysicist at the Carnegie Institution who developed the diamond anvil cell to reproduce Earth's-core pressures in the laboratory.
Ho:YAG laser
The Ho:YAG laser is a flashlamp-pumped solid-state laser emitting pulsed infrared light at 2120 nm, the standard for endoscopic urinary stone lithotripsy for more than 30 years.
Hoag's Object
Hoag's Object, also known as Hoag's Galaxy, is a ring galaxy 600 million light-years away in Serpens, discovered by Arthur Hoag in 1950 and regarded as a fine example of a rare galaxy class.
Hoare logic
Hoare logic, also known as Floyd–Hoare logic, is a formal system for reasoning about the correctness of imperative programs, introduced by Tony Hoare in 1969.
Hoba meteorite
The Hoba meteorite is the largest known intact meteorite on Earth, an iron of about 60 metric tons lying where it fell near Grootfontein in northern Namibia.
Hobby-Eberly Telescope
The Hobby-Eberly Telescope (HET) is a 10-meter fixed-elevation optical telescope at McDonald Observatory in west Texas, built for $13.9 million in 1997 and run by UT Austin, Penn State, and German universities.
Hobby-Eberly Telescope Dark Energy Experiment
The Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) is a spectroscopic survey on the 10-meter Hobby-Eberly Telescope in Texas measuring dark energy in the early universe.
Hobby–Rice theorem
The Hobby–Rice theorem is a 1965 result in analysis stating that finitely many measures on an interval can be simultaneously halved using signed pieces, key to L1 approximation.
Hochschild homology and cohomology
Hochschild homology and cohomology are pairs of derived-functor invariants of associative algebras, introduced by Gerhard Hochschild in 1945 and now extended to categories, schemes, and spectra.