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

L series (Japanese rockets)
L1551 (IR5)
L5 Society
La Silla Observatory
La Superba (Y Canum Venaticorum)
LABORATORY EQUIPMENT
labradorite
Lacaille, Abbé Nicolas Louis de (1713–1762)
Lacaille 9352
laccolith
LACE (Low-power Atmospheric Compensation Experiment)
Lacerta (constellation)
lacrimal apparatus
lacrimal gland
Lacrosse
lactase
lactase deficiency
lactation
lacteal
lactic acid
lactose
Lageos (Laser Geodynamics Satellite)
Lagomorpha
lagoon
Lagoon Nebula (M8, NGC 6523)
Lagrange, Joseph Louis de (1736–1813)
Lagrangian points
lahar
L'Aigle meteorite shower
Laika
Laing-Garrington effect
lake
Lake Vida
Lake Vostok
Lalande 21185
Lalande, Joseph Jérôme Le Français de (1732–1807)
Lamarck, Jean Baptiste Pierre Antoine de Monet (1744–1829)
Lamb, Willis Eugene, Jr. (1913–2008)
Lambda Bootis star
lambda calculus
Lambda Eridani star
Lambert, Johann Heinrich (1728–1777)
Lamé curve
laminar flow
laminate
land bridge
Land, Edwin Herbert (1909–1991)
Landau, Lev Davidovich (1908–1968)
Landsat
Landsteiner, Karl (1868–1943)
Langevin, Samuel Paul (1872–1946)
Langley, Samuel Pierpont (1834–1906)
Langley Research Center
Langley's adventitious angles
Langmuir, Irving (1881–1957)
Langton's ant
lanthanide
lanthanum
laparoscopy
lapilli
lapis lazuli
Laplace, Pierre Simon, Marquis de (1749–1827)
Large Binocular Telescope
Large Hadron Collider
large intestine
Large Magellanic Cloud
Large Millimeter Telescope
large numbers
Large Southern Array
large-scale structure
Larissa
Larmor precession
larva
laryngeal nerve
larynx
larynx, cartilages
larynx, intrinsic muscles
larynx, nerves and vessels
larynx, sinus and saccule
laser
laser propulsion
laser surgery
Lassell, William (1799–1880)
Lasswitz, Kurd (1848–1910)
Last and First Men
late heavy bombardment
latent heat
lateral
lateral line
laterite
late-type star
Latin square
latissimus dorsi
latitude
latitude variation
lattice
latus rectum
Laue, Max Theodor Felix von (1879–1960)
launch pad
LAUNCH SITES
launch vehicle
LauncherOne
Laurasia
lava
lava delta
lava flow
lava fountain
lava lake
lava tube
Laveran, Charles Louis Alphonse (1845-1922)
Lavoisier, Antoine Laurent (1743–1794)
Lawrence, Ernest Orlando (1901–1958)
lawrencium
law of mass action
laws of reflection
laxative
LCROSS (Lunar CRater Observing and Sensing Satellite)
LDEF (Long Duration Exposure Facility)
L-dopa
Le Chatelier's principle
Le Gentil, Guillaume Joseph Hyacinthe Jean Baptiste (1725–1792)
Le Prieur, Yves Paul Gaston (1885–1963)
Le Verrier, Urbain Jean Joseph (1811–1877)
leaching
lead
lead poisoning
lead-chamber process
leaf
Leakey, Louis Seymour Bazett (1903–1972)
Leakey, Richard Erskine Frere (1944–)
leap year
Leasat (Leased Satellite)
least squares
Leavitt, Henrietta Swan (1868–1921)
Lebedev, Valentin V. (1942–)
Lebesgue, Henri Leon (1875–1941)
Leblanc, Nicolas (1742–1806)
Lebombo bone
Leclanché cell
Leda
Lederberg, Joshua (1925–2008)
Lee, Tsung Dao (1926–)
Leeuwenhoek, Anton van (1632–1723)
left gastric artery
leg
Legendre, Adrien Marie (1752–1833)
legionnaire's disease
legume
leguminous plant
Leibniz, Gottfried Wilhelm (1646–1716)
Leibniz harmonic triangle
Leinster, Murray (1896–1975)
leishmaniasis
Leloir, Luis Federico (1906–1997)
Lem, Stanislaw (1921–2006)
Lemaître, Georges Édouard (1894–1966)
lemniscate of Bernoulli
Lemonnier, Pierre Charles (1715–1799)
Lenard, Philipp Eduard Anton (1862–1947)
length
Lenoir, Jean Joseph Étienne (1822–1900)
lens
lens (eye)
Lense-Thiring effect
lenticel
lenticular galaxy
LEO (low Earth orbit)
Leo (constellation)
Leo I
Leo II
Leo III
Leo Minor (constellation)
Leonhard Euler Telescope
Leonardo da Vinci (1452–1519)
Leonids
Leonov, Alexei Archipovich (1934–)
leprosy
lepton
Lepus (constellation)
LES (Lincoln Experimental Satellite)
leucine
Leucippus
leucite
leucoplast
leukemia
leukemia treatment
leukocyte
Leurechon, Jean (c. 1591–1670)
Leuschner Observatory
levator scapulae
levatores costarum
levée
lever
Levin, Gilbert (1925–)
Levy, David H. (1948–)
Lewis, C(live) S(taples) (1898–1963)
Lewis, Gilbert Newton (1875–1946)
Lewis Research Center
Lexell, Comet (D/1770 L1)
Ley, Willy (1906–1969)
Leyden jar
Liais, Emmanuel (1826–1900)
liana
Liar paradox
Libby, Willard Frank (1908–1980)
Libra (constellation)
libration
lichen
Lick Observatory
lidar (light detection and ranging)
Lie, Marius Sophus (1842–1899)
Lie algebra
Lie group
Liebig, Justus von (1803–1873)
life, classification
life, detection
life, extraterrestrial
life, in space
life, nature
life, origin
life, variety
Life, Conway's Game of
life cycle
life in lakes and rivers
life on land
life zone
lifetime, of extraterrestrial civilizations
lift
lifting-body
ligament
ligamentum nuchae
ligand
light
light barrier
light cone
light curve
light echo
light element
light flash phenomenon
light pollution
light time
light waves
light-gas gun
lighthouse
lightning
lightning rod
light-year
lignin
lignite
Lilienthal, Otto (1848–1896)
Lilly, John Cunningham (1915–2001)
limaçon of Pascal
limb
limb correction
limb darkening
limbic system
lime kiln
lime water
limestone
limit (mathematics)
limonite
limu
LINCOS
Lingbergh, Charles Augustus (1902–1974)
Lindblad, Bertil (1895–1965)
Lindsay, David (1878-1945)
Lindsay-Shapley Ring
line
line blanketing
line broadening
line of nodes
line ratio
line spectrum
linear (mathematics)
LINEAR (Lincoln Near Earth Asteroid Research) program
LINEAR, Comet (C/1999 S4)
linear accelerator
linear algebra
linear energy transfer
linear expansion
linear motor
linear system
LINER (low-ionization nuclear emission-line region)
lingual artery
linkage
Linnaeus, Carolus (1707–1778)
Liouville number
lips
lipase
lipid
lipid bilayer
Lipmann, Fritz Albert (1899–1986)
lipofuscin
Lippershey, Hans (c. 1570–c. 1619)
Lippincott, Sarah Lee (1920–2019)
Lippisch Ente
Lippmann, Gabriel (1845–1921)
LiPS (Living Plume Shield)
liquefaction of gases
liquid
liquid crystal display (LCD)
liquid-air cycle engine
liquid-fueled rocket
liquid-propellant rocket engine
liquids, expansion of
LISA (Laser Interferometer Space Antenna)
Lissajous figure
Lissajous orbit
Listeners, The
Lister, Joseph (1827–1912)
liter (unit)
lithium and the "lithium problem"
lithopanspermia
lithosphere
lithotrophs
litmus
Little Dipper
Little Dumbbell Nebula (M76, NGC 650 and 651)
Little Gem Annular Nebula (NGC 6818)
Little Joe
littoral cone
littoral zone
Littrow, Joseph Johann von (1781–1840)
lituus
liver
liver cancer
liver cancer treatment
liverwort
lizard
load
Lobachevsky, Nikolai Ivanovich (1793–1856)
Local Bubble
Local Group
local horizon
Local Interstellar Cloud
local standard of rest
Local Supercluster
localized solution
Loch Ness monster
Locke, John (1632–1704)
Locke, Richard Adams (1800–1871)
Lockman Hole
locks and keys
Lockyer, (Joseph) Norman (1836–1920)
locomotion
locomotive
loculus of Archimedes
locus
Lodge, Oliver Joseph (1851–1940)
lodranite
Loeb, Jacques (1859–1924)
loess
Loewi, Otto (1873–1961)
Löffler, Friedrich August Johannes (1852–1915)
logarithm
logarithmic spiral
logic
logic and the tools of philosophy
logic circuit
logical operation
logical positivism
Lo'ihi Underwater Volcanic Vent Mission Probe
Lomonosov, Mikhail Vasilievich (1711–1765)
lone pair
Long, Crawford Williamson (1815–1878)
long bone
Long March
long QT syndrome
longissimus capitis
longitude
long-period comet
long-period variable
longshore drift
Longshot, Project
loom
loop
LORAN
Lorenz, Edward Norton (1917–2008)
Lorenz, Konrad (1903–1989)
Lorentz, Henrik Antoon (1853–1928)
Lorentz contraction
Lorentz force turning
Lorentz transformation
Losat-X (Low Altitude Satellite Experiment)
Lost City meteorite
Lost In Space
lost languages
loudspeaker
Lousma, Jack Robert (1936–)
Lovejoy, Arthur Onck (1873–1962)
Lovelace, William Randolph, II (1907–1965)
Lovell, (Alfred Charles) Bernard (1913–2012)
Lovell, James Arthur, Jr. (1928–)
Lovell Telescope
Lovelock, James E. (1919–2022)
Low, Archibald Montgomery (1888–1956)
low Earth orbit (LEO)
low surface brightness galaxy
Lowell, Percival (1855–1916)
Lowell Observatory
lower back pain
lowest common multiple
loxodrome
Loyd, Sam (1841-1911)
LSA
LSAT
LSD
Lucas, (François) Edouard (Anatole) (1842–1891)
Lucas sequences
Lucian of Samosata (AD c. 120–180)
Lucid, Shannon Matilda Wells (1943–)
lucky number
Lucretius (c. 99–55 BC)
Ludwig, Carl Friedrich Wilhelm (1816–1895)
lumbar fascia
lumbar puncture
lumbar vertebra
lumen (unit)
luminance
luminosity
luminescence
luminosity class
luminosity function
luminous flux
luminous intensity
Lump Star (NGC 2023)
Luna
Lunan, Duncan (Alasdair) (1945–)
lunar eclipse
Lunar Landing Research Vehicle (LLRV)
Lunar Orbiter
lunar parallax
lunar phases
Lunar Prospector
Lunar Receiving Laboratory
Lunar Reconnaissance Orbiter
Lunar Roving Vehicle
Lunar Society of Birmingham
Lunar-A
lunar-orbit rendezvous
Lundin, Bruce T. (1919–2006)
lung cancer
lung cancer treatment
lung function tests
lung transplant
lung ventilation-perfusion scan
lungfish
lungs
lunisolar
Lunney, Glynn S. (1936–)
Lunokhod
lupus
Lupus (constellation)
Luria, Salvador Edward (1912–1991)
luteinizing hormone
lutetium
lux (unit)
Luyten, Willem Jacob (1899–1994)
Luyten 726-8 (UV Ceti)
Luyten 789-6
Lyapunov orbit
Lycopodiophyta
Lyman series
Lyman-alpha
Lyell, Charles (1797–1875)
lymph
lymph node
lymph vessel
lymphangioleiomyomatosis (LAMS)
lymphatic organ
lymphatic system
lymphocyte
lymphocytopenia
lymphoma
Lyndon B. Johnson Space Center
Lynen, Feodor Felix Konrad (1911–1979)
Lynx (constellation)
Lyra (constellation)
Lysithea
lysosome
lysozyme