All articles starting with N
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Nuliayoq Colles
Nuliayoq Colles is a 350 km-wide group of small hills (colles) on Venus at 48.00° N, 136.00° W, one of sixteen named colles on the planet, named for a woman per IAU convention.
Nulji of Silla
Nulji of Silla (눌지 마립간, reigned 417–458) was the nineteenth ruler of the Korean kingdom of Silla, who secured father-to-son succession for the Kim clan.
Null (SQL)
Null (SQL), often written NULL, is a special marker for a missing or inapplicable value, introduced by Edgar F. Codd, distinct from zero and the empty string.
Null character
The null character, abbreviated NUL and written '\0' in C, is a control character with all bits of its encoding set to zero, used to terminate C strings.
Null geodesics in the Schwarzschild metric
Null geodesics in the Schwarzschild metric are the paths of light rays in the curved spacetime outside a spherical mass, with unstable circular photon orbits at radius 3M.
Null hypothesis
The null hypothesis (H0) is the default proposition, typically stating that an effect is absent, which a statistical test attempts to reject in favor of an alternative.
Null infinity
Null infinity, denoted ℐ, is the boundary surface where outgoing light rays of an asymptotically flat spacetime end, introduced by Roger Penrose in 1963 via a conformal transformation.
Null Island
Null Island is the humorous name for 0°N 0°E in the Gulf of Guinea, where failed geocodes and missing coordinates default under WGS 84; a NOAA buoy, not land, marks the spot.
Null modem
A null modem is a serial cable or adapter that crosses the transmit and receive lines of RS-232 devices, letting two computers connect directly without modems.
Null semantics
Null semantics are the rules SQL uses to handle null, a placeholder for unknown or missing values, evaluating comparisons under three-valued logic whose truth values are true, false, and unknown.
Null set
A null set, also called a measure-zero set, is a measurable set of measure zero, like the rationals or the uncountable Cantor set, that integration treats as negligible.
Null steering
Null steering is an antenna array technique that adjusts the radiation pattern to place deep minima, called nulls, toward unwanted signals while receiving the desired signal, used in radar, sonar, and communications.
Null test
A null test is a statistical validation procedure in physics and astronomy that checks whether data constructed to contain no signal, such as differences of data splits, look like noise.
Null-space impedance control
Null-space impedance control is a robot control technique giving a redundant manipulator's unneeded joints compliant spring-damper behavior, so its body yields safely to physical contact while the end-effector task continues.
Null-space projection
Null-space projection is a control technique for redundant robots in which lower-priority commands are projected so they cannot interfere with higher-priority tasks like end-effector tracking.
Nullarbor Plain
Nullarbor Plain: vast arid, treeless limestone karst on southern Australia's Great Australian Bight, world's largest arid karst (~200,000-240,000 km²), an uplifted Miocene sea floor honeycombed with ancient caves, crossed by the 1917 Trans-Australian Railway.
Nullification (U.S. Constitution)
Nullification is the asserted right of a U.S. state to declare federal laws unconstitutional and block them within its borders. Originating in the 1798 Kentucky and Virginia Resolutions and tested in the 1832-1833 Nullification Crisis, it has been rejected by every court under the Supremacy Clause.
Nullity, revision and enforcement of inter-state arbitral awards
Nullity, revision and enforcement of inter-state arbitral awards is the doctrine that inter-state awards face no compulsory annulment, with review only by consent, as in two ICJ cases.
Nullmax
Nullmax (纽劢科技) is an autonomous driving and ADAS software company founded in Silicon Valley in 2016 by former Tesla engineers Xu Lei and Justin Song.
Numa Numa (video)
Numa Numa is Gary Brolsma's 2004 webcam lip-sync video to O-Zone's "Dragostea din tei", uploaded to Newgrounds on December 6, 2004; one of the internet's first viral videos, with an estimated 700 million views by 2006.
Numa Pompilius
Numa Pompilius, legendary second king of Rome (traditionally 715–672 BC), Sabine from Cures, successor of Romulus; credited with founding Roman religion, priesthoods, calendar, and the Egeria and Pythagoras legends.
Numab Therapeutics
Numab Therapeutics AG is a Swiss biotechnology company in Horgen, founded by David Urech, that develops multispecific antibody therapies for cancer and inflammation; its lead clinical asset is NM32, a T-cell engager targeting ROR1.
Numana
Numana: ancient Picenian town and Adriatic emporium on the Conero promontory, province of Ancona, Marche, Italy. Iron Age port from the 9th century BC, over 1,500 necropolis tombs, Tomb of the Queen, later Roman municipium.
Numayrid dynasty
The Numayrid dynasty (بنو نمير) was a Bedouin Arab principality of the Banu Numayr tribe that ruled Harran, al-Raqqa, and Saruj in northern Mesopotamia after the Hamdanids collapsed around 990.
Numazu
Numazu (沼津市) is a city in eastern Shizuoka Prefecture, Japan, on Suruga Bay south of Mount Fuji, gateway to the Izu Peninsula; a port, post station, and castle town, city status 1923, population about 183,000, known for dried horse mackerel and the View-O floodgate.
Numazu Port Deep Sea Aquarium
Numazu Port Deep Sea Aquarium (沼津港深海水族館, Coelacanth Museum) in Numazu, Japan, is the world's first aquarium specializing in deep-sea species, with 100+ Suruga Bay species and the only frozen coelacanth specimens on display worldwide.
Numb (Linkin Park song)
"Numb" is a 2003 single by Linkin Park, the closing track of Meteora, written a week before NRG Studios recording, produced by Don Gilmore; it peaked at No. 11 Billboard Hot 100, was mashed with Jay-Z's Encore, and has billions of streams.
Numbat
Numbat (Myrmecobius fasciatus), banded anteater or noombat: a small, strictly diurnal Australian marsupial, sole member of Myrmecobiidae, eating 15,000-20,000 termites daily with a 10-11 cm tongue; IUCN Near Threatened since 2026, EPBC Endangered, confined to south-west Western Australia and fenced sanctuaries.
Number
A number is a mathematical object used to count, measure, and label, built up in nested systems from the natural numbers to the integers, rationals, reals, and complex numbers.
Number (sports)
Uniform, squad, or jersey numbers in team sports: numerals identifying players, first worn by late-1890s rugby teams, adopted in MLB in 1929, governed by UEFA and FIFA rules, and sometimes retired to honor players.