A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

K star
Kaba meteorite
kakangariite
Kakeya needle problem
Kakehashi (aka COMETS)
Kakkab (Alpha Lupi)
Kaliningrad
Kaluza-Klein theory
kamacite
Kamerlingh Onnes, Heike (1853–1926)
kampyle of Eudoxus
Kant, Immanuel (1724–1804)
kaolinite
Kapitza, Peter Leonidovich (1894–1984)
Kaplan, Joseph (1902–1991)
Kaposi's sarcoma
kappa curve
Kaprekar constant
Kaprekar number
Kapteyn, Jacobus Cornelius (1851–1922)
Kapteyn's Star
Kapustin Yar
Kardashev, Nikolai S. (1932–2019)
Kardashev civilizations
Karin Cluster
Kármán, Theodore von (1881–1963)
Karrer, Paul (1889–1971)
karst
karyotype
Kasner, Edward (1876–1955)
Kastler, Alfred (1902–1984)
Kaus Australis (Epsilon Sagittarii)
Kawasaki disease
Kay, John (1704–c. 1764)
Keck Observatory
Keeler, James Edward (1857-1900)
Keenan's System (NGC 5216 and NGC 5218)
Kekulé von Stradonitz, Friedrich August (1829–1896)
Keldysh, Mstislav Vsevolodovich (1911–1978)
Kelly, Thomas (1930–2002)
kelvin (unit)
Kelvin, Lord (William Thomson) (1824–1907)
Kelvin-Helmholtz contraction
Kendall, Edward Calvin (1886–1972)
Kendrew, John Cowdery (1917–1997)
Kennedy, John F. (1916–1963)
Kennedy Space Center
Kennelly, Arthur Edwin (1861–1939)
Kepler, Johannes (1571–1630)
Kepler Mission
Kepler-30
Kepler-47
Keplerian rotation curve
Keplerian telescope
Kepler-Poinsot solids
Kepler's conjecture
Kepler's equation
Kepler's laws of planetary motion
Kepler's Star (SN Oph 1604)
keratin
kernite
kerogen
kerosene
Kerr black hole
Kerwin, Joseph Peter (1932–)
ketone
ketone bodies
ketonuria
ketosis
Kettering Bug
kettle hole
Key Hole (KH)
khamsin
Khayyám, Omar (1048–1122)
Khintchine's constant
Khorana, Har Gobind (1922–2011)
Kibalchich, Nikolai Ivanovitch (1854–1881)
Kibo module (Japanese Experiment Module, ISS)
kidney
kidney cancer
kidney machine
kidney stone
kieselguhr
Kiku (ETS, Engineering Test Satellite)
kiln
kilogram
kimberlite
kinase
kinematics
kinetic energy
kinetic temperature
kinetic theory of gases
kinetics, chemical
kingdom
kings problem
kinin
kinship puzzles
Kipp's apparatus
kipuka
Kirchhoff, Gustav Robert (1824–1887)
Kirchhoff's laws
Kirkman, Thomas Penyngton (1806–1895)
Kirkwood, Daniel (1814–1895)
Kirkwood gaps
Kiruna
kite
Kitt Peak National Observatory
Kittinger, Joseph W. (1928–2022)
KIWI (nuclear reactor series)
Kjeldahl method
Klaproth, Martin Heinrich (1743–1817)
Klein, Christian Felix (1849–1925)
Klein, Harold P. ("Chuck") (1921–2001)
Klein bottle
Klemplerer Rosette
Kleopatra (asteroid)
Klumpke-Roberts, Dorothea (1861–1942)
klystron
knee
knee disorders
knight's tour
knot
knot (unit)
Knuth's up-arrow notation
Koch, Robert (1843–1910)
Koch snowflake
Kochab (Beta Ursae Minoris)
Kocher, Emil Theodor (1841–1917)
Kodiak Launch Complex
Kohoutek, Comet (C/1973 E1)
Kolbe, Adolf Wilhelm Hermann (1818–1884)
Kolmogorov, Andrei Nikolaievich (1903–1987)
Komarov, Vladimir Mikhaylovich (1927–1967)
Korabl-Sputnik
Kordylewski Clouds
Korolev, Sergei Pavlovich (1907–1966)
Koronis family (of asteroids)
Kossel, Albrecht (1853–1927)
Kourou
Kraft, Christopher Colombus, Jr. (1924–)
Kramers' law
Kranz, Eugene "Gene" F. (1933–)
Krebs, Hans Adolf (1900–1981)
Krebs cycle
KREEP
Krieger, Robert L. (1916–1990)
Krikalev, Sergei Konstantinovich (1958–)
Krogh, Schack August Steenberg (1874–1949)
Kronecker, Leopold (1823–1891)
Krüger 60
krypton
K-T boundary
Kuhn, Richard (1900–1967)
Kuiper, Gerard Peter (1905–1973)
Kuiper Airborne Observatory
Kuiper Belt
Kuiper Belt object
Kummersdorf
Kupon
Kurzweg, Hermann H. (1908–2000)
Kusch, Polykarp (1911–1993)
Kwajalein Missile Range
kwashiorkor
kyanite
Kyokko