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</div> </div> </div> <main> <div class="md-page-wrapper"> <div id="content" class="md-content"> <div class="container super"> <div class="text-center super-title mt-40 mb-20"> <h1 class="display-2 m-0 d-inline-block"> Science & Tech<hr class="mt-5 m-0 rounded category-Science-Tech" /> </h1> </div> <div class="grid"> <div class="col-100 p-0 col-md-33"> <div class="p-10"> <div class="card card-lg super-hero-card-1 col-100"> <div class="card-media"> <a href="/story/how-do-black-holes-really-work" class="d-flex position-relative align-items-center justify-content-center" > <div class="w-100"> <img loading="eager" src="https://cdn.britannica.com/84/193284-131-66EAF092/merging-black-holes-binary-system-each-other-December-26-2015.jpg?w=768&h=432&c=crop" alt="The merger of two black holes and the gravitational waves that ripple outward as the black holes spiral toward each other. The black holes-which represent those detected by LIGO on Dec. 26, 2015-were 14 and 8 times the mass of the sun, until they merged," class="w-100" /> </div> </a> </div> <div class="card-body w-100 "> <a href="/story/how-do-black-holes-really-work" class="title font-weight-bold font-16">How Do Black Holes Really Work?</a> <div class="m-0 mt-5 description line-clamp clamp-2"> <p>What is really going on inside of those terrifying faraway entities?</p> </div> </div> </div> </div> <div class="credit ml-10 ">LIGO/T. Pyle</div> </div> <div class="col-100 p-0 col-md-33"> <div class="p-10"> <div class="card card-lg super-hero-card-2 card-horizontal card-md-vertical mt-20 mt-md-0 col-100"> <div class="card-media"> <a href="https://www.britannica.com/science/history-of-artificial-intelligence" class="d-flex position-relative align-items-center justify-content-center" > <div class="w-100"> <img loading="eager" src="https://cdn.britannica.com/81/191581-050-8C0A8CD3/Alan-Turing.jpg?w=768&h=432&c=crop" alt="Alan Turing" class="w-100" /> <div class="credit internal mt-10">© Fine Art Images—Heritage Images/age fotostock</div> </div> </a> </div> <div class="card-body w-100 "> <a href="https://www.britannica.com/science/history-of-artificial-intelligence" class="title font-weight-bold font-16">The History of Artificial Intelligence</a> <div class="m-0 mt-5 description line-clamp clamp-2"> A survey of important events and people in the field of AI, from the early works of British logician Alan Turing to advancements at the turn of the 21st century. </div> </div> </div> </div> <div class="credit ml-10 d-none d-md-block">© Fine Art Images—Heritage Images/age fotostock</div> </div> <div class="col-100 pt-40 pt-md-0 pl-10 pl-md-30 col-md-33 super-top-right-rail-links-section"> <h2 class="font-serif mb-10">Popular</h2> <ol> <li class="pb-20 d-flex align-items-center super-popular-item-1 category-Science-Tech"> <div class="imagelink-with-image-on-the-side card card-horizontal " > <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/story/whats-the-difference-between-a-solstice-and-an-equinox" ><p>The Difference Between a Solstice and Equinox</p></a> </div> <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/whats-the-difference-between-a-solstice-and-an-equinox"> <img loading="eager" src="https://cdn.britannica.com/90/202690-131-1D29B008/colorful-winter-sunset.jpg?w=200&h=150&c=crop" alt="Colorful winter sunset" width="200" height="150" /> </a> </div> </div> </li> <li class="pb-20 d-flex align-items-center super-popular-item-2 category-Science-Tech"> <div class="imagelink-with-image-on-the-side card card-horizontal " > <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/list/10-important-dates-in-pluto-history" ><p>10 Important Dates in Pluto History</p></a> </div> <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/list/10-important-dates-in-pluto-history"> <img loading="eager" src="https://cdn.britannica.com/05/172305-131-0C37A9F2/Pluto-Changing-Faces-surface-view-photographs-NASA-2003.jpg?w=200&h=150&c=crop" alt="Pluto. The Changing Faces of Pluto. Most detailed view to date of the entire surface of the dwarf planet Pluto, as constructed from multiple NASA Hubble Space Telescope photographs taken from 2002 to 2003." width="200" height="150" /> </a> </div> </div> </li> <li class="pb-20 d-flex align-items-center super-popular-item-3 category-Science-Tech"> <div class="imagelink-with-image-on-the-side card card-horizontal " > <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/list/defying-gravity-7-of-the-biggest-things-that-ever-flew" ><p>Defy Gravity: 7 of the Biggest Things That Flew</p></a> </div> <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/list/defying-gravity-7-of-the-biggest-things-that-ever-flew"> <img loading="eager" src="https://cdn.britannica.com/03/190903-131-A6E98E47/Hindenburg-flames-Lakehurst-Naval-Air-Station-New-May-6-1937.jpg?w=200&h=150&c=crop" alt="German Hindenburg Zeppelin Explodes while trying to dock at station in Lakehurst, New Jersey on May 6, 1937. It was the worlds largest airship" width="200" height="150" /> </a> </div> </div> </li> <li class=" d-flex align-items-center super-popular-item-4 category-Science-Tech"> <div class="imagelink-with-image-on-the-side card card-horizontal " > <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/list/6-of-the-worlds-most-dangerous-birds" ><p>6 of the World's Most Dangerous Birds</p></a> </div> <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/list/6-of-the-worlds-most-dangerous-birds"> <img loading="eager" src="https://cdn.britannica.com/58/152058-131-0EB52C8F/Ostriches.jpg?w=200&h=150&c=crop" alt="Close-up of ostriches (Struthio camelus) necks and heads; location unknown." width="200" height="150" /> </a> </div> </div> </li> </ol> </div> </div> <h2 class="mt-40">Editor's Picks</h2> <div class="grid super-editors-items"> <div class="col-100 p-10 col-md-25 super-editors-pick-1"> <div class="card card-base card-horizontal card-md-vertical col-100"> <div class="card-media"> <a href="/story/how-much-water-should-a-person-drink-in-a-day" class="d-flex position-relative align-items-center justify-content-center" > <div class="w-100"> <img loading="eager" src="https://cdn.britannica.com/32/234332-131-44668783/woman-drinking-glass-of-water-hydration.jpg?w=400&h=225&c=crop" alt="Shot of a woman drinking a glass of water at home. Drink sip hydration" class="w-100" /> </div> </a> </div> <div class="card-body w-100 "> <a href="/story/how-much-water-should-a-person-drink-in-a-day" class="title font-weight-bold font-16">How Much Water Should a Person Drink in a Day?</a> <div class="m-0 mt-5 description line-clamp clamp-2"> On average, women need to consume about 11 cups of water to stay hydrated each day, while men require approximately 15 cups. </div> </div> </div> </div> <div class="col-100 p-10 col-md-25 super-editors-pick-2"> <div class="card card-base card-horizontal card-md-vertical col-100"> <div class="card-media"> <a href="https://www.britannica.com/topic/epistemology" class="d-flex position-relative align-items-center justify-content-center" > <div class="w-100"> <img loading="eager" src="https://cdn.britannica.com/74/151874-050-649A0456/refraction-light-air-water-optical-illusion-straws.jpg?w=400&h=225&c=crop" alt="optical illusion: refraction of light" class="w-100" /> </div> </a> </div> <div class="card-body w-100 "> <a href="https://www.britannica.com/topic/epistemology" class="title font-weight-bold font-16">epistemology</a> <div class="m-0 mt-5 description line-clamp clamp-2"> Epistemology, the philosophical study of the nature, origin, and limits of human knowledge. The term is derived from the Greek epistēmē (“knowledge”) and logos (“reason”), and accordingly the field is sometimes referred to as the theory of knowledge. Epistemology has a long history within Western </div> </div> </div> </div> <div class="col-100 p-10 col-md-25 super-editors-pick-3"> <div class="card card-base card-horizontal card-md-vertical col-100"> <div class="card-media"> <a href="/story/how-fast-is-the-universe-expanding" class="d-flex position-relative align-items-center justify-content-center" > <div class="w-100"> <img loading="eager" src="https://cdn.britannica.com/27/238127-131-9A610712/galaxy-cluster-Abell-2744.jpg?w=400&h=225&c=crop" alt="Galaxy clusters like Abell 2744 can act as a natural cosmic lens, magnifying light from more distant, background objects through gravity. NASA's James Webb Space Telescope may be able to detect light from the first stars in the universe if they are gravitationally lensed by such clusters. (astronomy, space exploration, galaxies)" class="w-100" /> </div> </a> </div> <div class="card-body w-100 "> <a href="/story/how-fast-is-the-universe-expanding" class="title font-weight-bold font-16">How Fast Is the Universe Expanding?</a> <div class="m-0 mt-5 description line-clamp clamp-2"> Learn why the Hubble constant doesn’t seem to be very constant. </div> </div> </div> </div> <div class="col-100 p-10 col-md-25 super-editors-pick-4"> <div class="card card-base card-horizontal card-md-vertical col-100"> <div class="card-media"> <a href="/list/6-amazing-facts-about-gravitational-waves-and-ligo" class="d-flex position-relative align-items-center justify-content-center" > <div class="w-100"> <img loading="eager" src="https://cdn.britannica.com/20/188520-131-FA4C1A43/Laser-Interferometer-Gravitational-Wave-Observatory-Hanford-Washington-installations.jpg?w=400&h=225&c=crop" alt="The LIGO Laboratory operates two detector sites, one near Hanford in eastern Washington, and another near Livingston, Louisiana. This photo shows the Hanford detector site." class="w-100" /> </div> </a> </div> <div class="card-body w-100 "> <a href="/list/6-amazing-facts-about-gravitational-waves-and-ligo" class="title font-weight-bold font-16">6 Amazing Facts About Gravitational Waves and LIGO</a> <div class="m-0 mt-5 description line-clamp clamp-2"> Catch a gravitational wave or two. </div> </div> </div> </div> <div class="col-100 p-10 col-md-25 super-editors-pick-5"> <div class="card card-base card-horizontal card-md-vertical col-100"> <div class="card-media"> <a href="https://www.britannica.com/technology/nanotechnology" class="d-flex position-relative align-items-center justify-content-center" > <div class="w-100"> <img loading="eager" src="https://cdn.britannica.com/88/79488-050-9D5BFAE9/Examples-realms-magnitude-orders.jpg?w=400&h=225&c=crop" alt="The powers of 10" class="w-100" /> </div> </a> </div> <div class="card-body w-100 "> <a href="https://www.britannica.com/technology/nanotechnology" class="title font-weight-bold font-16">nanotechnology</a> <div class="m-0 mt-5 description line-clamp clamp-2"> Nanotechnology, the manipulation and manufacture of materials and devices on the scale of atoms or small groups of atoms. The “nanoscale” is typically measured in nanometres, or billionths of a metre (nanos, the Greek word for “dwarf,” being the source of the prefix), and materials built at this </div> </div> </div> </div> <div class="col-100 p-10 col-md-25 super-editors-pick-6"> <div class="card card-base card-horizontal card-md-vertical col-100"> <div class="card-media"> <a href="/list/6-questions-about-dna-answered" class="d-flex position-relative align-items-center justify-content-center" > <div class="w-100"> <img loading="eager" src="https://cdn.britannica.com/28/190928-131-CE088DB5/DNA-helix-concept-evolution-medicine-science.jpg?w=400&h=225&c=crop" alt="DNA helix in a futuristic concept of the evolution of science and medicine." class="w-100" /> </div> </a> </div> <div class="card-body w-100 "> <a href="/list/6-questions-about-dna-answered" class="title font-weight-bold font-16">6 Questions About DNA Answered</a> <div class="m-0 mt-5 description line-clamp clamp-2"> Important questions asked and answered, briefly. </div> </div> </div> </div> <div class="col-100 p-10 col-md-25 super-editors-pick-7"> <div class="card card-base card-horizontal card-md-vertical col-100"> <div class="card-media"> <a href="https://www.britannica.com/technology/deepfake" class="d-flex position-relative align-items-center justify-content-center" > <div class="w-100"> <img loading="eager" src="https://cdn.britannica.com/94/248994-050-ACACA5D2/Unreal-Keanu-Reeves-TikTok-account-on.jpg?w=400&h=225&c=crop" alt="TikTok account featuring a deepfake of Keanu Reeves" class="w-100" /> </div> </a> </div> <div class="card-body w-100 "> <a href="https://www.britannica.com/technology/deepfake" class="title font-weight-bold font-16">deepfake</a> <div class="m-0 mt-5 description line-clamp clamp-2"> Deepfake, synthetic media, including images, videos, and audio, generated by artificial intelligence (AI) technology that portray something that does not exist in reality or events that have never occurred. The term deepfake combines deep, taken from AI deep-learning technology (a type of machine </div> </div> </div> </div> <div class="col-100 p-10 col-md-25 super-editors-pick-8"> <div class="card card-base card-horizontal card-md-vertical col-100"> <div class="card-media"> <a href="/story/what-causes-the-northern-and-southern-lights" class="d-flex position-relative align-items-center justify-content-center" > <div class="w-100"> <img loading="eager" src="https://cdn.britannica.com/17/170717-131-54B1DB08/Aurora-Borealis.jpg?w=400&h=225&c=crop" alt="Northern lights or Southern lights, also called Aurora Borealis. Luminous phenomenon of Earth's atmosphere. (magnetism; luminous atmospheric display)" class="w-100" /> </div> </a> </div> <div class="card-body w-100 "> <a href="/story/what-causes-the-northern-and-southern-lights" class="title font-weight-bold font-16">What Causes the Northern and Southern Lights?</a> <div class="m-0 mt-5 description line-clamp clamp-2"> What causes the auroras—that is, the northern lights and the southern lights? </div> </div> </div> </div> </div> <div class="grid mt-40"> <div class="col-100 col-md-40 pr-0 pr-md-30"> <h2>Spotlight: Mummification</h2> <div class="font-serif"> <div class="mb-20 mb-md-0"><p>A team of scientists recently recreated the face of Peru's most famous mummy, "Juanita," or the "Ice Maiden." The girl is thought to have been sacrificed when she was between the ages of 13 and 15 some 500 years ago. Mummified by centuries of ice and snow, the body was well-preserved and is just one example of how mummification can occur naturally.</p></div> </div> </div> <ul class="col-100 col-md-60 super-spotlight-links"> <li class="super-spotlight-card-1"> <a class="d-block" href="/story/thats-a-wrap-methods-of-mummification"> <img loading="lazy" src="https://cdn.britannica.com/95/195995-131-7BD26B09/mummy-man-Egyptian-Ptolemaic-name-collection-Musee.jpg?w=920&h=518&c=crop" alt="This extremely well preserved Egyptian mummy is that of a man who lived during the Ptolemaic Period. 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Influenza flu" width="200" height="150" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/list/10-ways-of-looking-at-cells" >10 Ways of Looking at Cells</a> <div class="font-weight-light font-serif font-14 line-clamp clamp-2 ilf-description">Learn about 10 cutting-edge microscopy tools that scientists are using to explore the internal structure of cells. </div> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal mb-20 super-featured-categories-col-1-item-4" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/list/13-questions-about-how-the-human-body-works-answered"> <img loading="lazy" src="https://cdn.britannica.com/20/125820-131-D8170E4F/veins-arteries-human.jpg?w=200&h=150&c=crop" alt="pulmonary veins and arteries, circulation, cardiovascular system, human anatomy, (Netter replacement project - SSC)" width="200" height="150" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/list/13-questions-about-how-the-human-body-works-answered" >13 Questions About How the Human Body Works Answered</a> <div class="font-weight-light font-serif font-14 line-clamp clamp-2 ilf-description">Blood, brains, lungs, skin, and more.</div> </div> </div> </ul> </div> <div class="col-100 col-md-33"> <h3>Astronomy</h3> <ul class="p-0"> <div class="imagelink-with-image-on-the-side card card-horizontal mb-20 super-featured-categories-col-2-item-1" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/9-ghostly-planets"> <img loading="lazy" src="https://cdn.britannica.com/30/133930-131-580E6710/Background-bubble-planets-clouds-astrology-astronomy-bubbles.jpg?w=200&h=150&c=crop" alt="Background: abstract bubble planets with clouds. astrology, astronomy, atomosphere, big bang, bubbles, fantasy, future, galaxy, universe, stars" width="200" height="150" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/story/9-ghostly-planets" >9 Ghostly Planets</a> <div class="font-weight-light font-serif font-14 line-clamp clamp-2 ilf-description">Were they ever out there to begin with?</div> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal mb-20 super-featured-categories-col-2-item-2" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/why-are-planets-round"> <img loading="lazy" src="https://cdn.britannica.com/17/157617-131-CE5D5AA5/Solar-system-illustration.jpg?w=200&h=150&c=crop" alt="Solar system illustration. (planets; sun)" width="200" height="150" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/story/why-are-planets-round" >Why Are Planets Round?</a> <div class="font-weight-light font-serif font-14 line-clamp clamp-2 ilf-description">There are a lot of strange things in the universe, so why are planets round instead of every shape imaginable?</div> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal mb-20 super-featured-categories-col-2-item-3" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/how-fast-is-the-universe-expanding"> <img loading="lazy" src="https://cdn.britannica.com/27/238127-131-9A610712/galaxy-cluster-Abell-2744.jpg?w=200&h=150&c=crop" alt="Galaxy clusters like Abell 2744 can act as a natural cosmic lens, magnifying light from more distant, background objects through gravity. NASA's James Webb Space Telescope may be able to detect light from the first stars in the universe if they are gravitationally lensed by such clusters. (astronomy, space exploration, galaxies)" width="200" height="150" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/story/how-fast-is-the-universe-expanding" >How Fast Is the Universe Expanding?</a> <div class="font-weight-light font-serif font-14 line-clamp clamp-2 ilf-description">Learn why the Hubble constant doesn’t seem to be very constant.</div> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal mb-20 super-featured-categories-col-2-item-4" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/telescopes-seeing-stars"> <img loading="lazy" src="https://cdn.britannica.com/60/190760-131-F1576E0B/space-background-telescope-silhouette-NASA-image-elements.jpg?w=200&h=150&c=crop" alt="Infinite space background with silhouette of telescope. This image elements furnished by NASA." width="200" height="150" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/story/telescopes-seeing-stars" >Telescopes: Seeing Stars</a> <div class="font-weight-light font-serif font-14 line-clamp clamp-2 ilf-description">For the last 400 years, telescopes have changed our view of the universe.</div> </div> </div> </ul> </div> <div class="col-100 col-md-33"> <h3>Mathematics</h3> <ul class="p-0"> <div class="imagelink-with-image-on-the-side card card-horizontal mb-20 super-featured-categories-col-3-item-1" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="https://www.britannica.com/biography/al-Khwarizmi"> <img loading="lazy" src="https://cdn.britannica.com/24/188424-050-BEA232B4/Al-Khwarizmi-USSR-postage-stamp-1983.jpg?w=200&h=150&c=crop" alt="Al-Khwārizmī" width="200" height="150" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="https://www.britannica.com/biography/al-Khwarizmi" >al-Khwārizmī</a> <div class="font-weight-light font-serif font-14 line-clamp clamp-2 ilf-description">Al-Khwārizmī was a Muslim mathematician and astronomer whose major works introduced Hindu-Arabic numerals and the concepts of algebra into European mathematics. Latinized versions of his name and of his most famous book title live on in the terms algorithm and algebra. Al-Khwārizmī lived in</div> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal mb-20 super-featured-categories-col-3-item-2" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/unusual-counting-systems"> <img loading="lazy" src="https://cdn.britannica.com/41/191041-131-7ECE668A/bunch-numbers.jpg?w=200&h=150&c=crop" alt="bunch of numbers" width="200" height="150" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/story/unusual-counting-systems" >Unusual Counting Systems</a> <div class="font-weight-light font-serif font-14 line-clamp clamp-2 ilf-description">In everyday life we use a base-10 counting system, but that is not something that has always been used in history.</div> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal mb-20 super-featured-categories-col-3-item-3" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="https://www.britannica.com/biography/Euclid-Greek-mathematician"> <img loading="lazy" src="https://cdn.britannica.com/46/8446-050-BC92B998/Euclid-woodcut-1584.jpg?w=200&h=150&c=crop" alt="Euclid" width="200" height="150" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="https://www.britannica.com/biography/Euclid-Greek-mathematician" >Euclid</a> <div class="font-weight-light font-serif font-14 line-clamp clamp-2 ilf-description">Euclid was the most prominent mathematician of Greco-Roman antiquity, best known for his treatise on geometry, the Elements. Of Euclid’s life nothing is known except what the Greek philosopher Proclus (c. 410–485 ce) reports in his “summary” of famous Greek mathematicians. According to him, Euclid</div> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal mb-20 super-featured-categories-col-3-item-4" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="https://www.britannica.com/biography/Aryabhata-I"> <img loading="lazy" src="https://cdn.britannica.com/03/121803-004-547BDB4D/Aryabhata-I-statue-Inter-University-Centre-for.jpg?w=200&h=150&c=crop" alt="Aryabhata I" width="200" height="150" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="https://www.britannica.com/biography/Aryabhata-I" >Aryabhata</a> <div class="font-weight-light font-serif font-14 line-clamp clamp-2 ilf-description">Aryabhata was an astronomer and the earliest Indian mathematician whose work and history are available to modern scholars. He is also known as Aryabhata I or Aryabhata the Elder to distinguish him from a 10th-century Indian mathematician of the same name. He flourished in Kusumapura—near</div> </div> </div> </ul> </div> </div> </div></div> </div> </main> <div id="md-footer"></div> <footer class="md-footer footer-wrapper hide-on-edit"> <div class="footer-bck"> <DIV class="marketing-FOOTER_NEWSLETTER marketing-content" data-marketing-id="FOOTER_NEWSLETTER"><div class="md-footer-newsletter-form pt-10 mb-30 mx-15 mx-sm-120"> <div class="font-18"> <strong>History at your fingertips –</strong> Sign up here to see what happened On This Day, every day in your inbox! </div> <div class="p-30"> <div class="newsletter-form-container"> <form class="newsletter-form" method="post" action="/newsletter-subscription/EB_ON_THIS_DAY"> <div class="form-group grid d-flex justify-content-center"> <div class="col-sm-50 col-100"> <label class="sr-only" for="enter-your-email">Enter your email</label> <input id="enter-your-email" type="email" name="email" class="form-control font-18 p-10" placeholder="Enter your email" pattern="[a-z0-9._%+-]+@[a-z0-9.-]+\.[a-z]{2,4}$" required> </div> <div class="col-sm-auto col-100 mt-5 mt-sm-0"> <button type="submit" class="btn btn-outline-white" style="width: 100%; height:100%;">Subscribe</button> </div> </div> <div class="text-white pt-30 text-opacity"> By signing up for this email, you are agreeing to news, offers, and information from Encyclopaedia Britannica.<br> Click here to view our <a class="link-white text-decoration-underline" href="https://corporate.britannica.com/privacy-policy2" target="_blank" rel="noopener nofollow">Privacy Notice</a>. 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