Ptolemy
An early Baroque artist's rendition of Claudius Ptolemaeus
Born	c. AD 90 Egypt
Died	c. AD 168 (aged 77–78) Alexandria, Egypt
Occupation	mathematician, geographer, astronomer, astrologer

Claudius Ptolemy ( /ˈtɒləmi/; Greek: Κλαύδιος Πτολεμαῖος, Klaudios Ptolemaios; Latin: Claudius Ptolemaeus; c. AD 90 – c. AD 168), was a Greek-Roman citizen of Egypt who wrote in Greek.^[1] He was a mathematician, astronomer, geographer, astrologer, and poet of a single epigram in the Greek Anthology.^[2][3] He lived in Egypt under Roman rule, and is believed to have been born in the town of Ptolemais Hermiou in the Thebaid. This theory, proposed by Theodore Meliteniotes, could be correct, but it is late (ca. 1360) and unsupported.^[4] There is no reason to suppose that he ever lived anywhere else than Alexandria,^[4] where he died around AD 168.^[5]

Ptolemy was the author of several scientific treatises, at least three of which were of continuing importance to later Islamic and European science. The first is the astronomical treatise now known as the Almagest (in Greek, Ἡ Μεγάλη Σύνταξις, "The Great Treatise", originally Μαθηματικὴ Σύνταξις, "Mathematical Treatise"). The second is the Geography, which is a thorough discussion of the geographic knowledge of the Greco-Roman world. The third is the astrological treatise known sometimes in Greek as the Apotelesmatika (Ἀποτελεσματικά), more commonly in Greek as the Tetrabiblos (Τετράβιβλος "Four books"), and in Latin as the Quadripartitum (or four books) in which he attempted to adapt horoscopic astrology to the Aristotelian natural philosophy of his day.

Background[link]

Engraving of a crowned Ptolemy being guided by the muse Astronomy, from Margarita Philosophica by Gregor Reisch, 1508. Although Abu Ma'shar believed Ptolemy to be one of the Ptolemies who ruled Egypt after the conquest of Alexander the title ‘King Ptolemy’ is generally viewed as a mark of respect for Ptolemy's elevated standing in science.

The name Claudius is a Roman nomen; the fact that Ptolemy bore it indicates he lived under the Roman rule of Egypt with the privileges and political rights of Roman citizenship. It would have suited custom if the first of Ptolemy's family to become a citizen (whether he or an ancestor) took the nomen from a Roman called Claudius who was responsible for granting citizenship. If, as was common, this was the emperor, citizenship would have been granted between AD 41 and 68 (when Claudius, and then Nero, were emperors). The astronomer would also have had a praenomen, which remains unknown. It may have been Tiberius, as that praenomen was very common among those whose families had been granted citizenship by these emperors.^{[citation needed]}

Ptolemaeus (Πτολεμαῖος – Ptolemaios) is a Greek name. It occurs once in Greek mythology, and is of Homeric form.^[6] It was common among the Macedonian upper class at the time of Alexander the Great, and there were several of this name among Alexander's army, one of whom made himself King of Egypt in 323 BC: Ptolemy I Soter. All the kings after him, until Egypt became a Roman province in 30 BC, were also Ptolemies.

Perhaps for no other reason than the association of name, the 9th century Persian astronomer Abu Ma'shar assumed Ptolemy to be member of Egypt's royal lineage, stating that the ten kings of Egypt who followed Alexander were wise "and included Ptolemy the Wise, who composed the book of the Almagest". Abu Ma'shar recorded a belief that a different member of this royal line "composed the book on astrology and attributed it to Ptolemy". We can evidence historical confusion on this point from Abu Ma'shar's subsequent remark “It is sometimes said that the very learned man who wrote the book of astrology also wrote the book of the Almagest. The correct answer is not known”.^[7] There is little evidence on the subject of Ptolemy's ancestry, apart from what can be drawn from the details of his name (see above); however modern scholars refer to Abu Ma’shar’s account as erroneous,^[8] and it is no longer doubted that the astronomer who wrote the Almagest also wrote the Tetrabiblos as its astrological conterpart.^[9]

Beyond his being considered a member of Alexandria's Greek society, few details of Ptolemy's life are known for certain. He wrote in Ancient Greek and is known to have utilized Babylonian astronomical data.^[10][11] He was a Roman citizen, but most scholars conclude that Ptolemy was ethnically Greek,^[12][13][14] although some suggest he was a Hellenized Egyptian.^[13][15][16] He was often known in later Arabic sources as "the Upper Egyptian",^[17] suggesting he may have had origins in southern Egypt.^[18] Later Arabic astronomers, geographers and physicists referred to him by his name in Arabic: بطليموس‎ Batlaymus.^[19]

Astronomy [link]

The Almagest is the only surviving comprehensive ancient treatise on astronomy. Babylonian astronomers had developed arithmetical techniques for calculating astronomical phenomena; Greek astronomers such as Hipparchus had produced geometric models for calculating celestial motions. Ptolemy, however, claimed to have derived his geometrical models from selected astronomical observations by his predecessors spanning more than 800 years, though astronomers have for centuries suspected that his models' parameters were adopted independently of observations.^[20] Ptolemy presented his astronomical models in convenient tables, which could be used to compute the future or past position of the planets.^[21] The Almagest also contains a star catalogue, which is an appropriated version of a catalogue created by Hipparchus. Its list of forty-eight constellations is ancestral to the modern system of constellations, but unlike the modern system they did not cover the whole sky (only the sky Hipparchus could see). Through the Middle Ages it was spoken of as the authoritative text on astronomy, with its author becoming an almost mythical figure, called Ptolemy, King of Alexandria.^[22] The Almagest was preserved, like most of Classical Greek science, in Arabic manuscripts (hence its familiar name). Because of its reputation, it was widely sought and was translated twice into Latin in the 12th century, once in Sicily and again in Spain.^[23] Ptolemy's model, like those of his predecessors, was geocentric and was almost universally accepted until the appearance of simpler heliocentric models during the scientific revolution.

His Planetary Hypotheses went beyond the mathematical model of the Almagest to present a physical realization of the universe as a set of nested spheres,^[24] in which he used the epicycles of his planetary model to compute the dimensions of the universe. He estimated the Sun was at an average distance of 1210 Earth radii while the radius of the sphere of the fixed stars was 20,000 times the radius of the Earth.^[25]

Ptolemy presented a useful tool for astronomical calculations in his Handy Tables, which tabulated all the data needed to compute the positions of the Sun, Moon and planets, the rising and setting of the stars, and eclipses of the Sun and Moon. Ptolemy's Handy Tables provided the model for later astronomical tables or zījes. In the Phaseis (Risings of the Fixed Stars) Ptolemy gave a parapegma, a star calendar or almanac based on the hands and disappearances of stars over the course of the solar year.

Geography[link]

Ptolemy's other main work is his Geographia. This also is a compilation of what was known about the world's geography in the Roman Empire during his time. He relied somewhat on the work of an earlier geographer, Marinos of Tyre, and on gazetteers of the Roman and ancient Persian Empire, but most of his sources beyond the perimeter of the Empire were unreliable.^{[citation needed]}

The first part of the Geographia is a discussion of the data and of the methods he used. As with the model of the solar system in the Almagest, Ptolemy put all this information into a grand scheme. Following Marinos, he assigned coordinates to all the places and geographic features he knew, in a grid that spanned the globe. Latitude was measured from the equator, as it is today, but Ptolemy preferred in book 8 to express it as the length of the longest day rather than degrees of arc (the length of the midsummer day increases from 12h to 24h as one goes from the equator to the polar circle). In books 2 through 7, he used degrees and put the meridian of 0 longitude at the most western land he knew, the "Blessed Islands", probably the Cape Verde islands (not the Canary Islands, as long accepted) as suggested by the location of the six dots labelled the "FORTUNATA" islands near the left extreme of the blue sea of Ptolemy's map here reproduced.

A 15th-century manuscript copy of the Ptolemy world map, reconstituted from Ptolemy's Geographia (circa 150), indicating the countries of "Serica" and "Sinae" (China) at the extreme east, beyond the island of "Taprobane" (Sri Lanka, oversized) and the "Aurea Chersonesus" (Malay Peninsula).

Ptolemy also devised and provided instructions on how to create maps both of the whole inhabited world (oikoumenè) and of the Roman provinces. In the second part of the Geographia he provided the necessary topographic lists, and captions for the maps. His oikoumenè spanned 180 degrees of longitude from the Blessed Islands in the Atlantic Ocean to the middle of China, and about 80 degrees of latitude from Shetland to anti-Meroe (east coast of Africa); Ptolemy was well aware that he knew about only a quarter of the globe, and an erroneous extension of China southward suggests his sources did not reach all the way to the Pacific Ocean.

The maps in surviving manuscripts of Ptolemy's Geographia, however, date only from about 1300, after the text was rediscovered by Maximus Planudes. It seems likely that the topographical tables in books 2–7 are cumulative texts – texts which were altered and added to as new knowledge became available in the centuries after Ptolemy (Bagrow 1945). This means that information contained in different parts of the Geography is likely to be of different date.

A printed map from the 15th century depicting Ptolemy's description of the Ecumene, (1482, Johannes Schnitzer, engraver).

Maps based on scientific principles had been made since the time of Eratosthenes (3rd century BC), but Ptolemy improved projections. It is known that a world map based on the Geographia was on display in Augustodunum, Gaul in late Roman times. In the 15th century Ptolemy's Geographia began to be printed with engraved maps; the earliest printed edition with engraved maps was produced in Bologna in 1477, followed quickly by a Roman edition in 1478 (Campbell, 1987). An edition printed at Ulm in 1482, including woodcut maps, was the first one printed north of the Alps. The maps look distorted as compared to modern maps, because Ptolemy's data was inaccurate. One reason is that Ptolemy estimated the size of the Earth as too small: while Eratosthenes found 700 stadia for a great circle degree on the globe, in the Geographia Ptolemy uses 500 stadia. It is highly probable that these were the same stadion since Ptolemy switched from the former scale to the latter between the Syntaxis and the Geographia, and severely readjusted longitude degrees accordingly. If they both used the Attic stadion of about 185 meters, then the older estimate is 1/6 too large, and Ptolemy's value is 1/6 too small, a difference explained as due to ancient scientists' use of simple methods of measuring the earth, which were corrupted either high or low by a factor of 5/6, due to air's bending of horizontal light rays by 1/6 of the Earth's curvature.^{[citation needed]} See also Ancient Greek units of measurement and History of geodesy.

Because Ptolemy derived many of his key latitudes from crude longest day values, his latitudes are erroneous on average by roughly a degree (2 degrees for Byzantium, 4 degrees for Carthage), though capable ancient astronomers knew their latitudes to more like a minute. (Ptolemy's own latitude was in error by 14'.) He agreed (Geographia 1.4) that longitude was best determined by simultaneous observation of lunar eclipses, yet he was so out of touch with the scientists of his day that he knew of no such data more recent than 500 years before (Arbela eclipse). When switching from 700 stadia per degree to 500, he (or Marinos) expanded longitude differences between cities accordingly (a point first realized by P.Gosselin in 1790), resulting in serious over-stretching of the Earth's east-west scale in degrees, though not distance. Achieving highly precise longitude remained a problem in geography until the invention of the marine chronometer at the end of the 18th century. It must be added that his original topographic list cannot be reconstructed: the long tables with numbers were transmitted to posterity through copies containing many scribal errors, and people have always been adding or improving the topographic data: this is a testimony to the persistent popularity of this influential work in the history of cartography.

Astrology[link]

The mathematician Claudius Ptolemy 'the Alexandrian' as imagined by a 16th century artist

Ptolemy has been referred to as “a pro-astrological authority of the highest magnitude”.^[26] His astrological treatise, a work in four parts, is known by the Greek term Tetrabiblos, or the Latin equivalent Quadripartitum: ‘Four Books’. Ptolemy's own title is unknown, but may have been the term found in some Greek manuscripts: Apotelesmatika, roughly meaning 'Astrological Outcomes,' 'Effects' or ‘Prognostics’.^[27][28]

As a source of reference the Tetrabiblos is said to have "enjoyed almost the authority of a Bible among the astrological writers of a thousand years or more".^[29] It was first translated from Arabic into Latin by Plato of Tivoli (Tiburtinus) in 1138, while he was in Spain.^[30] The Tetrabiblos is an extensive and continually reprinted treatise on the ancient principles of horoscopic astrology. That it did not quite attain the unrivaled status of the Almagest was perhaps because it did not cover some popular areas of the subject, particularly electional astrology (interpreting astrological charts for a particular moment to determine the outcome of a course of action to be initiated at that time), and medical astrology, which were later adoptions.

The great popularity that the Tetrabiblos did possess might be attributed to its nature as an exposition of the art of astrology and as a compendium of astrological lore, rather than as a manual. It speaks in general terms, avoiding illustrations and details of practice. Ptolemy was concerned to defend astrology by defining its limits, compiling astronomical data that he believed was reliable and dismissing practices (such as considering the numerological significance of names) that he believed to be without sound basis.

Much of the content of the Tetrabiblos was collected from earlier sources; Ptolemy's achievement was to order his material in a systematic way, showing how the subject could, in his view, be rationalized. It is, indeed, presented as the second part of the study of astronomy of which the Almagest was the first, concerned with the influences of the celestial bodies in the sublunar sphere. Thus explanations of a sort are provided for the astrological effects of the planets, based upon their combined effects of heating, cooling, moistening, and drying.

Ptolemy's astrological outlook was quite practical: he thought that astrology was like medicine, that is conjectural, because of the many variable factors to be taken into account: the race, country, and upbringing of a person affects an individual's personality as much if not more than the positions of the Sun, Moon, and planets at the precise moment of their birth, so Ptolemy saw astrology as something to be used in life but in no way relied on entirely.

A collection of one hundred aphorisms about astrology called the Centiloquium, ascribed to Ptolemy, was widely reproduced and commented on by Arabic, Latin and Hebrew scholars, and often bound together in medieval manuscripts after the Tetrabiblos as a kind of summation. It is now believed to be a much later pseudoepigraphical composition. The identity and date of the actual author of the work, referred to now as Pseudo-Ptolemy, remains the subject of conjecture.

Music[link]

Ptolemy also wrote an influential work, Harmonics, on music theory and the mathematics of music. After criticizing the approaches of his predecessors, Ptolemy argued for basing musical intervals on mathematical ratios (in contrast to the followers of Aristoxenus and in agreement with the followers of Pythagoras) backed up by empirical observation (in contrast to the overly theoretical approach of the Pythagoreans). Ptolemy wrote about how musical notes could be translated into mathematical equations and vice versa in Harmonics. This is called Pythagorean tuning because it was first discovered by Pythagoras. However, Pythagoras believed that the mathematics of music should be based on the specific ratio of 3:2 whereas Ptolemy merely believed that it should just generally involve tetrachords and octaves. He presented his own divisions of the tetrachord and the octave, which he derived with the help of a monochord. Ptolemy's astronomical interests also appeared in a discussion of the "music of the spheres". See: Ptolemy's intense diatonic scale.

Optics[link]

His Optics is a work that survives only in a poor Arabic translation and in about twenty manuscripts of a Latin version of the Arabic, which was translated by Eugene of Palermo (c. 1154). In it Ptolemy writes about properties of light, including reflection, refraction, and colour. The work is a significant part of the early history of optics.^[31] and influenced the more famous 11th century Optics by Alhazen (Ibn al-Haytham). The work is also important for the early history of perception. Ptolemy combined the mathematical, philosophical and physiological traditions. He held an extramission-intromission theory of vision: the rays (or flux) from the eye formed a cone, the vertex being within the eye, and the base defining the visual field. The rays were sensitive, and conveyed information back to the observer’s intellect about the distance and orientation of surfaces. Size and shape were determined by the visual angle subtended at the eye combined with perceived distance and orientation. This was one of the early statements of size-distance invariance as a cause of perceptual size and shape constancy, a view supported by the Stoics.^[32] Ptolemy offered explanations of many phenomena concerning illumination and colour, size, shape, movement and binocular vision. He also divided illusions into those caused by physical or optical factors and those caused by judgemental factors. He offered an obscure explanation of the sun or moon illusion (the enlarged apparent size on the horizon) based on the difficulty of looking upwards.^[33][34]

Named after Ptolemy[link]

There are several characters or items named after Ptolemy, including:

• The crater Ptolemaeus on the Moon;
• The crater Ptolemaeus^[35] on Mars;
• the asteroid 4001 Ptolemaeus;
• a character in the fantasy series The Bartimaeus Trilogy: this fictional Ptolemy is a young magician (from Alexandria) whom Bartimaeus loved; he made the journey into "the Other Place" being hunted by his cousin, because he was a magician;
• the name of Celestial Being's carrier ship in the anime Mobile Suit Gundam 00.
• track number 10 on Selected Ambient Works 85–92 by Aphex Twin.
• the Ptolemy Stone used in the mathematics courses at both St. John's College campuses.
• English astronomer and TV presenter Sir Patrick Moore has a cat named Ptolemy.

Pop culture[link]

In Jonathan Stroud's Bartimaeus Trilogy, the djinni Bartimaeus often assumes Ptolemy's form and frequently refers to him as one of his favorite masters. The third and final book in the series is also called Ptolemy's Gate.

See also[link]

Atlas portal

• Pei Xiu
• Ptolemy's Canon – a dated list of kings used by ancient astronomers.
• Ptolemy Cluster – star cluster described by Ptolemaeus
• Ptolemy's theorem – mathematical theorem described by Ptolemaeus
• Ptolemy's table of chords
• Ptolemy's world map – map of the ancient world as described by Ptolemaeus.
• Zhang Heng

Footnotes[link]

References[link]

Texts and translations[link]

• Bagrow, L. (January 1, 1945). "The Origin of Ptolemy's Geographia". Geografiska Annaler (Geografiska Annaler, Vol. 27) 27: 318–387. doi:10.2307/520071. ISSN 16513215. JSTOR 520071. 
• Berggren, J. Lennart, and Alexander Jones. 2000. Ptolemy's Geography: An Annotated Translation of the Theoretical Chapters. Princeton and Oxford: Princeton University Press. ISBN 0-691-01042-0.
• Campbell, T. (1987). The Earliest Printed Maps. British Museum Press. 
• Hübner, Wolfgang, ed. 1998. Claudius Ptolemaeus, Opera quae exstant omnia Vol III/Fasc 1: ΑΠΟΤΕΛΕΣΜΑΤΙΚΑ (= Tetrabiblos). De Gruyter. ISBN 978-3-598-71746-8 (Bibliotheca scriptorum Graecorum et Romanorum Teubneriana). (The most recent edition of the Greek text of Ptolemy's astrological work, based on earlier editions by F. Boll and E. Boer.)
• Lejeune, A. (1989) L'Optique de Claude Ptolémée dans la version latine d'après l'arabe de l'émir Eugène de Sicile. [Latin text with French translation]. Collection de travaux de l'Académie International d'Histoire des Sciences, No. 31. Leiden: E.J.Brill.
• Neugebauer, Otto (1975). A History of Ancient Mathematical Astronomy. I-III. Berlin and New York: Sprnger Verlag. 
• Nobbe, C. F. A., ed. 1843. Claudii Ptolemaei Geographia. 3 vols. Leipzig: Carolus Tauchnitus. (The most recent edition of the complete Greek text)
• Ptolemy. 1930. Die Harmonielehre des Klaudios Ptolemaios, edited by Ingemar Düring. Göteborgs högskolas årsskrift 36, 1930:1. Göteborg: Elanders boktr. aktiebolag. Reprint, New York: Garland Publishing, 1980.
• Ptolemy. 2000. Harmonics, translated and commentary by Jon Solomon. Mnemosyne, Bibliotheca Classica Batava, Supplementum, 0169-8958, 203. Leiden and Boston: Brill Publishers. ISBN 90-04-11591-9
• Robbins, Frank E. (ed.) 1940. Ptolemy Tetrabiblos. Cambridge, Massachusetts: Harvard University Press (Loeb Classical Library). ISBN 0-674-99479-5.
• Smith, A.M. (1996) Ptolemy's theory of visual perception: An English translation of the Optics with introduction and commentary. Transactions of the American Philosophical Society, Vol. 86, Part 2. Philadelphia: The American Philosophical Society.
• Stevenson, Edward Luther (trans. and ed.). 1932. Claudius Ptolemy: The Geography. New York: New York Public Library. Reprint, New York: Dover, 1991. (This is the only complete English translation of Ptolemy's most famous work. Unfortunately, it is marred by numerous mistakes and the placenames are given in Latinised forms, rather than in the original Greek).
• Stückelberger, Alfred, and Gerd Graßhoff (eds). 2006. Ptolemaios, Handbuch der Geographie, Griechisch-Deutsch. 2 vols. Basel: Schwabe Verlag. ISBN 978-3-7965-2148-5. (Massive 1018 pp. scholarly edition by a team of a dozen scholars that takes account of all known manuscripts, with facing Greek and German text, footnotes on manuscript variations, color maps, and a CD with the geographical data)
• Taub, Liba Chia (1993). Ptolemy's Universe: The Natural Philosophical and Ethical Foundations of Ptolemy's Astronomy. Chicago: Open Court Press. ISBN 0-8126-9229-2. 
• Ptolemy's Almagest, Translated and annotated by G. J. Toomer. Princeton University Press, 1998

External links[link]

Wikiquote has a collection of quotations related to: Ptolemy

Wikimedia Commons has media related to: Ptolemy

• Online Galleries, History of Science Collections, University of Oklahoma Libraries High resolution images of works by Ptolemy in .jpg and .tiff format.

Primary sources[link]

• Ptolemy's Tetrabiblos at LacusCurtius (English translation of a portion of the material, with introductory material)
• Entire Tetrabiblos of J.M. Ashmand's 1822 translation.
• Ptolemy's Geography at LacusCurtius (English translation, incomplete)
• Extracts of Ptolemy on the country of the Seres (China) (English translation)
• Geographia (the Balkan Provinces, with old maps) at Sorin Olteanu's LTDM Project (soltdm.com)
• Almagest books 1–13 The complete text of Heiberg's edition (PDF) Greek.
• Almagest books 1–6 (Greek) with preface (Latin) @ archive.org

Secondary material[link]

• Arnett, Bill (2008). "Ptolemy, the Man". obs.nineplanets.org. http://obs.nineplanets.org/psc/theman.html. Retrieved 2008-11-24. 
• Danzer, Gerald (1988). "Cartographic Images of the World on the Eve of the Discoveries". The Newberry Library. http://www.newberry.org/smith/slidesets/ss08.html. Retrieved 26 November 2008. 
• Haselein, Frank (2007). "Κλαυδιου Πτολεμιου: Γεωγραφικῆς Ύφηγήσεως (Geographie)" (in German and some English). Frank Haselein. http://wwwuser.gwdg.de/~fhasele/ptolemaeus/index.html. Retrieved 2008-11-24. 
• Houlding, Deborah (2003). "The Life & Work of Ptolemy". Skyscript.co. http://www.skyscript.co.uk/ptolemy.html. Retrieved 2008-11-24. 
• Jones, Alexander (ed.) 2010. Ptolemy in Perspective: Use and Criticism of his Work from Antiquity to the Nineteenth Century. New York: Series: Archimedes, Vol. 23., ISBN 978-90-481-2787-0
• Toomer, Gerald J. (1970). "Ptolemy (Claudius Ptolemæus)". In Gillispie, Charles. Dictionary of Scientific Biography. 11. New York: Scribner & American Council of Learned Societies. pp. 186–206. ISBN 9780684101149. http://www.u.arizona.edu/~aversa/scholastic/Dictionary%20of%20Scientific%20Biography/Ptolemy%20(Toomer).pdf. 
• Sprague, Ben (2001–2007). "Claudius Ptolemaeus (Ptolemy): Representation, Understanding, and Mathematical Labeling of the Spherical Earth". Center for Spatially Integrated Social Science. http://www.csiss.org/classics/content/76. Retrieved 26 November 2008. 

Animated illustrations[link]

• Java simulation of the Ptolemaic System – at Paul Stoddard's Animated Virtual Planetarium, Northern Illinois University
• Animation of Ptolemy's Two Solar Hypotheses
• Epicycle and Deferent Demo – at Rosemary Kennett's website at the University of Syracuse
• Flash animation of Ptolemy's universe. (best in Internet Explorer)

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Aphex Twin
In Turin, Italy in March 2007.
Background information
Birth name	Richard David James
Born	(1971-08-18) 18 August 1971 (age 40) Limerick, Ireland
Origin	Lanner, Cornwall, United Kingdom
Genres	Electronic, ambient, IDM, acid techno
Occupations	Musician, composer, remixer
Instruments	Synthesizers, piano, electronics, harpsichord, organ, percussion, laptop, softsynth, turntables, drum machine, guitar, bass guitar, computer, sequencer, sampler
Years active	1985–present
Labels	Warp Records Sire Records Rephlex Records
Associated acts	Universal Indicator, Mike & Rich

Richard David James (born 18 August 1971), best known under the pseudonym Aphex Twin, is a British electronic musician and composer. He founded the record label Rephlex Records in 1991 with Grant Wilson-Claridge. He was described by The Guardian as "the most inventive and influential figure in contemporary electronic music."^[1]

Aphex Twin has also recorded music under the aliases AFX, Blue Calx, Bradley Strider, Caustic Window, DJ Smojphace, GAK, Martin Tressider, Polygon Window, Power-Pill, Prichard D. Jams, Q-Chastic, Tahnaiya Russell, The Dice Man, Soit-P.P., and speculatively The Tuss.

Aphex Twin has released recordings on Rephlex, Warp, R&S, Sire, Mighty Force, Rabbit City, and Men Records.

History[link]

Early years[link]

Richard David James was born to Welsh parents Lorna and Derek James in St. Munchin's Limerick Regional Maternity Hospital, Ireland. He grew up in Lanner, Cornwall, enjoying, along with two older sisters, a "very happy" childhood during which they, according to James, "were pretty much left to do what [they] wanted."^[2] He "liked growing up there, being cut off from the city and the rest of the world".^[3] James attended Redruth School, located in Redruth, Cornwall.^[4]

According to musician Benjamin Middleton, James started producing music at the age of 12.^[5] As a teenager he was a disc jockey at the Shire Horse Inn in St Ives, with Tom Middleton at the Bowgie Inn in Crantock, and also along the numerous beaches around Cornwall. James studied for a National Diploma in Engineering from 1988 to 1990 (aged 16 to 18) at Cornwall College. Talking about his studies, James has said that "music and electronics went hand in hand."^[6] James graduated from college; according to an engineering lecturer, however, he often had his headphones on during practical lessons, "no doubt thinking through the mixes he'd be working on later".^[7]

Early career: early 1990s[link]

In 1989 James met and befriended Grant Wilson-Claridge when working as a DJ on alternate weeks at the Bowgie pub, near Newquay in Cornwall. Wilson-Claridge was intrigued by James's sets and was surprised to discover that James was playing tapes of his own music.

James' first release was the 12-inch EP Analogue Bubblebath on Mighty Force Records in 1991. It was first released under the moniker Aphex Twin, later changed to AFX. The track "En Trance to Exit" was made in collaboration with Tom Middleton, also known as Schizophrenia.^[8] The EP got on the playlist of Kiss FM, an influential London radio station, which helped the release to become a success.^[9]

In 1991, James and Wilson-Claridge founded Rephlex Records to promote "innovation in the dynamics of Acid — a much-loved and -misunderstood genre of house music forgotten by some and indeed new to others, especially in Britain."^[10]

Between 1991 and 1993, James released two Analogue Bubblebath EPs as AFX, and an EP under Bradley Strider, Bradley's Beat. James moved to London to take an electronics course at Kingston Polytechnic, but at the time admitted to David Toop that his "electronics studies were already slipping away as a career in the techno business took precedence." After quitting his course, James remained in London and released a number of albums and EPs on Warp Records and other labels under many aliases including AFX, Polygon Window, and Power-Pill. A number of James' tracks (released under the aliases Blue Calx, The Dice Man, and others) appeared on various compilations. Local legend has it that James lived on the roundabout in Elephant and Castle, South London during his early years in the capital - in fact he lived in a nearby disused bank.^[2][11]

Gaining success: 1992–1995[link]

	"Ageispolis" noicon Sample of "Ageispolis" from the album Selected Ambient Works 85-92.
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	"Ventolin (Video Version)" noicon Sample of "Ventolin (Video Version)" from the album ...I Care Because You Do.
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The first full-length Aphex Twin album, Selected Ambient Works 85–92, was released in 1992 on R&S Records. It received high ratings and praise from critics. John Bush of Allmusic described it as a "watershed of ambient music".^[12] In 2002, Rolling Stone wrote of the album: "Aphex Twin expanded way beyond the ambient music of Brian Eno by fusing lush soundscapes with oceanic beats and bass lines."^[13] Pitchfork Media's review called it, "among the most interesting music ever created with a keyboard and a computer."^[14] Critics also noted that the songs were recorded on cassette and that the sound quality was "relatively poor".

In 1992, he also released the EPs Xylem Tube EP and Digeridoo (first played by DJ Colin Faver on London's Kiss FM) as Aphex Twin, as Power-Pill the Pac-Man EP based on the arcade game Pac-Man, and two of his four Caustic Window EPs. "Digeridoo" reached #55 in the UK Singles Chart, and was later described as foreshadowing drum and bass by Rolling Stone.^[15] "Digeridoo" was recorded initially for the benefit of FIZZ-BOMB (at the Shire Horse, St Ives, Cornwall). These early releases came out on Rephlex Records, Mighty Force of Exeter, and R&S Records of Belgium.^[16]

In 1993, James released Analogue Bubblebath 3. He also released a single titled "On"; his second Bradley Strider EP, Bradley's Robot; two more Caustic Window EPs; and his first releases on Warp Records, Surfing on Sine Waves and "Quoth" under the alias Polygon Window.

Warp Records pressed and released a follow-up to Selected Ambient Works 85-92, Selected Ambient Works Volume II in 1994. The sound was much less beat and melody-driven than the previous volume. All of the track names were described with pie chart symbols, each of which was meant to be paired with a corresponding image in the album jacket, with exception for one song, which was named "Blue Calx". To decipher song titles, listeners had to compare the length of each track with the size of each pie chart symbol. For example, the first title, which is often labelled cliffs, is realised by pairing the first symbol with the first image, which is that of a rocky cliffside.^[17] James claimed in The Wire magazine and other media that these songs were inspired by lucid dreams and synaesthesia. Other releases are a fourth Analogue Bubblebath; GAK, derived from early demos sent to Warp Records; and Classics, a compilation album that includes "Digeridoo" and the Xylem Tube EP.

For his 1995 release, ...I Care Because You Do, James used an image of his face for the album cover, a motif that would continue on many of his later records. The album was a compilation of songs composed between 1990 and 1994 and represented a mish-mash of Aphex Twin's various music styles. This was James's last record of the 1990s to use mostly analogue synthesizers. He commissioned Western classical-music composer Philip Glass to create an orchestral version of one of the songs from this album, "Icct Hedral", which appeared on the Donkey Rhubarb EP.^[18]

Jungle, DSP, and laptops: 1995–1999[link]

In 1995 (primarily with Hangable Auto Bulb, a near anagram of Analogue Bubblebath), James began releasing more material composed on computers, combining a jungle sound with nostalgic childhood themes and computer-generated acid lines.

James's early adoption of software synthesizers predated the later popularity of using computers to make music. In the mid-to-late 1990s, his music gradually gained more mainstream appeal, as he released Richard D. James Album and Expert Knob Twiddlers (a collaboration with fellow dance producer µ-ziq) in 1996, "Come to Daddy" in 1997 (#36 on UK charts) and "Windowlicker" in 1999 (#16 on UK charts). Two pop songs that heavily use Digital Signal Processing (DSP) techniques, "Come to Daddy" and "Windowlicker" were shown on MTV and became cover features for music magazines such as NME. The videos for both singles were directed by British artist Chris Cunningham and caused controversy on release because of their disturbing images and themes.

In 1998, Aphex Twin's track "[rhubarb]" (from Selected Ambient Works Volume II) appeared as part of the BBC's digital widescreen test transmission, which was on loop for many months as the service was introduced across the UK.^[19]

Prepared piano, laptops, and more DSP: 2000–2003[link]

In 2001 Aphex Twin released drukqs, a two-CD album that featured computer controlled piano songs influenced by Erik Satie and John Cage. Many of the tracks' names are written in the Cornish language (i.e., 'jynweythek' translatable as 'machinemusic'). Also included were abrasive, fast, and meticulously programmed computer-made songs. Rolling Stone described the piano songs as "aimlessly pretty".^[20] Some reviewers concluded that drukqs was released as a contract breaker with Warp Records—a credible guess, as James's next big release was released on his own Rephlex label. James claimed to interviewers he had accidentally left an MP3 player labelled "Aphex Twin—unreleased tracks" on a plane, containing a large set of new songs, and rushed the album release to preempt an Internet leak.^[21] He also released a short EP titled 2 Remixes By AFX the same year as Drukqs. It featured two remixes, the originals being from 808 State and DJ Pierre. In addition, there is one untitled third track that consists of an SSTV image, which consists of mostly of high-pitched sounds, which can be decoded to a viewable image by proper software such as MultiMode (for Macintosh) or MMSSTV (for Windows).

Synthesizers and drum machines: 2004–present[link]

In late 2004, rumours of James's return to an acid techno-based sound were realised with the Analord series, an 11-part series of EPs with 42 total tracks, averaging 2–4 tracks per EP. The series was created by playing and sequencing analogue and digital electronic music equipment such as synthesizers and drum machines. The series was recorded on magnetic tape and then later pressed on vinyl.

James was meticulous about the whole process of recording, mastering, and pressing. James has said Rephlex Records was strict on quality control, trying out various pressing-plant companies until they felt it sounded perfect. To James's ears, vinyl or tape is better than digital, as no two copies are the same. However, label co-owner Grant Wilson-Claridge convinced James to release a CD compilation, Chosen Lords, which included 10 selected tracks from the Analord series. For the Analord series James used his collection of vintage synthesizer and drum machines, some of which were quite rare by that time. Some of the record inserts have pictures of rare synthesizers like the Synton Fenix, and the notoriously difficult-to-program Roland MC-4 sequencer, as well as the legendary Roland TB-303.

In 2007 media reports indicated that Aphex Twin was recording under a new alias called The Tuss. Rephlex Records has denied that Aphex Twin is The Tuss, but Aphex Twin fans and the media have ignored Rephlex's denial and The Tuss is treated as yet another Aphex Twin project;^[22][23] further evidence being provided by the fact that all Tuss tracks are published in the BMI Repertoire under the name JAMES RICHARD DAVID.^[24]

Some of Aphex Twin's music was featured in the award winning documentary about the atrocities of shark finning, Sharkwater.

In March 2009 Steve Beckett of Warp Records announced a new album for a possible release but the album never materialised.^[25] However, 20 more tracks were added to the Analord series in December 2009, only available through download from the Rephlex Records website.

In an October 2010 interview with British magazine Another Man, James stated that he had completed 6 albums, one of which was a remake of the unreleased Melodies from Mars, originally produced around the time of Richard D. James Album.^[26] In June 2011, he spoke to Spanish magazine EL PAIS. When asked about the 6 albums, he answered 'More than 10 or 11 are already compiled, and many more songs are orphans.' He also revealed that a new album 'will show in a while' and that the reason there has been so long since his last album was that he was waiting for a divorce from his wife.^[27]

Background details[link]

	"Jynweythek" noicon Sample of "Jynweythek" from the album Drukqs.
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	"Vordhosbn" noicon Sample of "Vordhosbn" from the album Drukqs.
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	"Fenix Funk 5" noicon Sample of "Fenix Funk 5" from the EP Analord 10.
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	"VBS.Redlof. B" noicon Sample of "VBS.Redlof. B" from the EP Analord 11.
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The Aphex Twin name[link]

The name Aphex is derived from Aphex Systems Limited, a brand of audio signal processing equipment (itself derived from "analogue effects").^{[dubious – discuss]} It is used with permission, as acknowledged on the back sleeves of Richard D. James Album and drukqs. He has explained in interviews that the Twin portion of his moniker is used in memory of his brother, also named Richard James, who died at birth in 1968.

Artwork[link]

James's own face, grinning or distorted in some way, is a common theme in his album covers, his music videos, and the songs themselves. The cover of I Care Because You Do features a painting of James, while the cover of Richard D. James Album presents a close-up photograph. His face is transplanted onto other peoples' bodies in the music videos of "Come to Daddy" and "Windowlicker". Near the end of the second track of the "Windowlicker" single (commonly referred to as "Equation"), a photo of James' face is embedded as a steganogram which is revealed when run through spectral analysis.^[28] Another embedded image of James, along with collaborator Tom Jenkinson, appears in the third track of 2 Remixes by AFX, "Bonus High Frequency Sounds", encoded in SSTV format, with text relating to the release.

James has used his own photography for some of his releases, such as the elaborate album sleeve for Selected Ambient Works Volume II.

Braindance[link]

Richard's own Rephlex Records label, which he co-owns with Grant Wilson-Claridge, coined the term Braindance in 1991 to describe Aphex Twin's music.^[22][29][30] Rephlex Records' official definition of Aphex Twin and his followers' music is quoted as follows: "Braindance is the genre that encompasses the best elements of all genres, e.g traditional, classical, electronic music, popular, modern, industrial, ambient, hip-hop, electro, house, techno, breakbeat, hardcore, ragga, garage, drum and bass, etc."^[31]

Braindance applies to forward-thinking electronic music that can appeal to the mind as well as the desire to dance and party. Examples including Ed-DMX's Breakin' records label, µ-ziq's Planet-mu label, the Aphex Twin EP Come to Daddy and Astrobotnia Parts 1, 2 & 3.^[32]

Influences[link]

At age 17, Richard D. James mentioned these influences: "Phonic Boy, Computer World, Mental Telepathy, Industrial Inc., Tomita, Tangerine Dream". Mixmaster Morris mentions on the "I Luv AFX" BBC Radio 1 Breezeblock session that James' preferred moniker while working as a DJ in Cornwall was Phonic Boy on Dope. More recently, he has said that he gets inspiration from "everyday sounds that can be emulated/reconstructed electronically, quality techno, especially from Europe, which overshadows the current hardcore pop crap." When asked about what is next for electronic music, he said "acid-techno, ambient-techno." Avant-garde music has been an influence on James, including artists such as Kraftwerk, Can, Tangerine Dream, Tod Dockstader, Xenakis, Piero Umiliani, Bernard Parmegiani, Karlheinz Stockhausen,^[33] John Cage, and the French composer Erik Satie for his piano works and his ideas for furniture music.

In acknowledgment of another influence, James released Music from the BBC Radiophonic Workshop, a compilation of music recorded by the pioneers of BBC Radiophonic Workshop, which included artists such as Delia Derbyshire,^[34] on his own label, Rephlex Records.

Aphex Twin has said, "I don't really like rock & roll." Despite this, he has mentioned being a fan of Led Zeppelin, citing their use of breakbeats as an influence, as well as Pink Floyd for their psychedelic music.^[35]

Many songs include sounds from and references to the ZX Spectrum. For instance, "Carn Marth" from Richard D. James Album includes the tape-loading noise of the game Sabre Wulf.

Influence on others[link]

The London Sinfonietta has performed arrangements of Aphex Twin tracks.^[36] In 2005, the orchestra Alarm Will Sound released Acoustica: Alarm Will Sound Performs Aphex Twin. The album consists of acoustic arrangements of some of James's electronic tracks. He has also had an influence on rock bands like Radiohead.^[37] However, he has dismissed the notion of going on tour with them: "I wouldn't play with them since I don't like them."^[35] Despite his previous comments, he premiered new music alongside Radiohead guitarist/composer Jonny Greenwood in a 2011 collaboration with Polish composer Krzysztof Penderecki.^[38] The animator David Firth has much of his work influenced and soundtracked by Aphex Twin.^[39]

Intelligent Dance Music[link]

The term 'intelligent dance music', or IDM, was coined in August 1993 by the IDM mailing list based at hyperreal.org, as a term to describe the sound pioneered by the Warp Records Artificial Intelligence Series. The series featured Aphex Twin tracks (under a different pseudonym), as well as early productions from labelmates such as Autechre and LFO. The usage of this term spread in the USA and on internet messageboards, but the term is still a source of controversy and derision amongst the artists and fans, including Aphex Twin. As of October 2011 the list is still active.

I just think it's really funny to have terms like that. It's basically saying, 'this is intelligent and everything else is stupid.' It's really nasty to everyone else's music. (laughs) It makes me laugh, things like that. I don't use names. I just say that I like something or I don't.

—Aphex Twin^[40]

Aphex Twin refers to his own breakbeat tracks as breakbeat, jungle, or drum and bass interchangeably. Other genres that he indulges in include acid, ambient, ambient techno, noise, and many more.

Equipment[link]

During an interview with Future Music, Richard said he likes using Ableton Live but prefers Liveslice for beat editing/stretching. Asked what equipment did use, he responded "Raveolution 309, the Raven Max, MC-909 limited edition, Quasimidi Van Helden, MAM Freebass 383, Roland DJ-70, E-15, SP-808, Akai S3200, Behringer MX602A and all the Behringer effects that copy other things."^[44]

Aphex Twin's press[link]

James described himself in The Guardian as follows: "I'm just some irritating, lying, ginger kid from Cornwall who should have been locked up in some youth detention centre. I just managed to escape and blag it into music."^[1]

James said he composed ambient techno music at the age of 13; he claims to have "over 100 hours" of unreleased music, and to have made his own software to compose with, including algorithmic processes that automatically generate beats and melodies; in addition he claims to experience synaesthesia, and that he is able to incorporate lucid dreaming into the process of making music.^[45]

He lives in southeast London in a converted bank, which was formerly the Bank of Cyprus and then HSBC. Contrary to popular opinion, however, he does not own the silver structure in the centre of the roundabout at Elephant and Castle. This is, in fact, the Michael Faraday Memorial, containing a power transformer for the Northern Line, which James jokingly claimed to be buying in an interview with The Face magazine in 2001.^[2] Some of these rumours are hard to confirm as he has been known to spread mistruths in the prankster tradition, making such claims as only sleeping two to three hours a night.^[46]

Stockhausen vs. The Technocrats[link]

In November 1995, The Wire published an article titled "Advice to Clever Children". In the process of producing the interview, a package of tapes containing music from several artists, including Aphex Twin, was sent to Karlheinz Stockhausen.

Stockhausen commented:

I heard the piece Aphex Twin of Richard James (sic) carefully: I think it would be very helpful if he listens to my work "Song of the Youth," which is electronic music, and a young boy's voice singing with himself. Because he would then immediately stop with all these post-African repetitions, and he would look for changing tempi and changing rhythms, and he would not allow to repeat any rhythm if it varied to some extent and if it did not have a direction in its sequence of variations.^[47]

Aphex Twin, a fan of Stockhausen, responded:

"I thought he should listen to a couple of tracks of mine: "Digeridoo", then he'd stop making abstract, random patterns you can't dance to".^[47]

ZX81 competition[link]

Richard claims to have produced sound on a Sinclair ZX81 (a machine with no sound hardware) at the age of 11:

When I was 11, I won 50 pounds in a competition for writing this program that made sound on a ZX81. You couldn't make sound on a ZX81, but I played around with machine code and found some codes that retuned the TV signal so that it made this really weird noise when you turned the volume up.^[2]

Discography[link]

Studio albums (as Aphex Twin)

• Selected Ambient Works 85–92 (1992)
• Selected Ambient Works Volume II (1994)
• ...I Care Because You Do (1995)
• Richard D. James Album (1996)
• Drukqs (2001)

References[link]

External links[link]

Wikimedia Commons has media related to: Aphex Twin

• Aphex Twin at Warp Records
• Aphex Twin at the Open Directory Project
• Aphex Twin discography at Discogs.

Carl Sagan
Sagan in 1980
Born	(1934-11-09)November 9, 1934 Brooklyn, New York, U.S.
Died	December 20, 1996(1996-12-20) (aged 62) Seattle, Washington, U.S.
Residence	United States[1]
Nationality	United States
Fields	Astronomy, astrophysics, cosmology, astrobiology, space science, planetary science
Institutions	Cornell University Harvard University Smithsonian Astrophysical Observatory University of California, Berkeley
Alma mater	University of Chicago (B.A.), (B.Sc.), (M.Sc.), (PhD)
Known for	Search for Extra-Terrestrial Intelligence (SETI) Cosmos: A Personal Voyage Cosmos Voyager Golden Record Pioneer plaque Contact Pale Blue Dot
Notable awards	NASA Distinguished Public Service Medal (1977) Pulitzer Prize for General Non-Fiction (1978) Oersted Medal (1990) National Academy of Sciences Public Welfare Medal (1994)

Carl Edward Sagan ( /ˈseɪɡɪn/; November 9, 1934 – December 20, 1996) was an American astronomer, astrophysicist, cosmologist, author, science popularizer, and science communicator in astronomy and natural sciences. He published more than 600 scientific papers^[2] and articles and was author, co-author or editor of more than 20 books. He advocated scientifically skeptical inquiry and the scientific method, pioneered exobiology and promoted the Search for Extra-Terrestrial Intelligence (SETI).

Sagan is known for his popular science books and for the award-winning 1980 television series Cosmos: A Personal Voyage, which he narrated and co-wrote.^[3] The book Cosmos was published to accompany the series. Sagan wrote the novel Contact, the basis for a 1997 film of the same name.

Early life[link]

Carl Sagan was born in Brooklyn, New York,^[4] to a Ukrainian Jewish family. His father, Sam Sagan, was an immigrant garment worker from Kamenets-Podolsk, Ukraine;^[5] his mother, Rachel Molly Gruber, a housewife. Carl was named in honor of Rachel's biological mother, Chaiya Clara, in Sagan's words, "the mother she never knew." Sagan graduated from Rahway High School in Rahway, New Jersey, in 1951.^[6]

He had a sister, Carol, and the family lived in a modest apartment near the Atlantic Ocean, in Bensonhurst, a Brooklyn neighborhood. According to Sagan, they were Reform Jews, the most liberal of the three main Jewish groups. Both Sagan and his sister agree that their father was not especially religious, but that their mother "definitely believed in God, and was active in the temple ... and served only Kosher meat."^[6]:12 During the height of the Depression, his father had to accept a job as a theater usher.

According to biographer Keay Davidson, Sagan's "inner war" was a result of his close relations with both his parents, who were in many ways "opposites." Sagan traced his later analytical urges to his mother, a woman who had known "extreme poverty as a child," and had grown up almost homeless in New York City during World War I and the 1920s.^[6]:2 She had her own intellectual ambitions as a young woman, but they were blocked by social restrictions, because of her poverty, her being a woman and wife, and her Jewish ethnicity. Davidson notes that she therefore "worshiped her only son, Carl. He would fulfill her unfulfilled dreams."^[6]:2

However, his "sense of wonder" came from his father, who was a "quiet and soft-hearted escapee from the Czar." In his free time, he gave apples to the poor, or helped soothe labor-management tensions within New York's "tumultuous" garment industry.^[6]:2 Although he was "awed" by Carl's "brilliance, his boyish chatter about stars and dinosaurs," he took his son's inquisitiveness in stride, as part of his growing up.^[6]:2 In his later years as a writer and scientist, Sagan would often draw on his childhood memories to illustrate scientific points, as he did in his book, Shadows of Forgotten Ancestors.^[6]:9 Sagan describes his parents' influence on his later thinking:

My parents were not scientists. They knew almost nothing about science. But in introducing me simultaneously to skepticism and to wonder, they taught me the two uneasily cohabiting modes of thought that are central to the scientific method.^[7]

1939 World's Fair[link]

Sagan recalls that one of his best experiences was when he was four or five years old, his parents took him to the 1939 New York World's Fair. The exhibits became a turning point in his life. He later recalled the moving map of the "America of Tomorrow" exhibit: "It showed beautiful highways and cloverleaves and little General Motors cars all carrying people to skyscrapers, buildings with lovely spires, flying buttresses—and it looked great!"^[6]:14 At other exhibits, he remembered how a flashlight that shined on a photoelectric cell created a cracking sound, and how the sound from a tuning fork became a wave on an oscilloscope. He also witnessed the future media technology that would replace radio: television. Sagan wrote:

Plainly, the world held wonders of a kind I had never guessed. How could a tone become a picture and light become a noise?^[6]:14

He also saw one of the Fair's most publicized events, the burial of a time capsule at Flushing Meadows, which contained mementos of the 1930s to be recovered by Earth's descendants in a future millennium. "The time capsule thrilled Carl," writes Davidson. As an adult, Sagan and his colleagues created similar time capsules, but ones that would be sent out into the galaxy. These were the Pioneer plaque and the Voyager Golden Record records, all of which were spinoffs of Sagan's memories of the World Fair.^[6]:15

World War II[link]

During World War II, Sagan's family worried about the fate of their European relatives. Sagan, however, was generally unaware of the details of the ongoing war. He writes, "Sure, we had relatives who were caught up in the Holocaust. Hitler was not a popular fellow in our household ... But on the other hand, I was fairly insulated from the horrors of the war." His sister, Carol, said that their mother "above all wanted to protect Carl ... She had an extraordinarily difficult time dealing with World War II and the Holocaust."^[6]:15 Sagan's book, The Demon-Haunted World (1996), included his memories of this conflicted period, when his family dealt with the realities of the war in Europe, but tried to prevent it from undermining his optimistic spirit.^[7]

Inquisitiveness about nature[link]

Soon after entering elementary school, he began to express a strong inquisitiveness about nature. Sagan recalled taking his first trips to the public library alone, at the age of five, when his mother got him a library card. He wanted to learn what stars were, since none of his friends or their parents could give him a clear answer:

I went to the librarian and asked for a book about stars ... And the answer was stunning. It was that the Sun was a star but really close. The stars were suns, but so far away they were just little points of light ... The scale of the universe suddenly opened up to me. It was a kind of religious experience. There was a magnificence to it, a grandeur, a scale which has never left me. Never ever left me.^[6]:18

About the time he was six or seven, he and a close friend took trips to the American Museum of Natural History in New York City. While there, they went to the Hayden Planetarium and walked around the museum's exhibits of space objects, such as meteorites, and displays of dinosaurs and animals in natural settings. Sagan writes about those visits:

I was transfixed by the dioramas—lifelike representations of animals and their habitats all over the world. Penguins on the dimly lit Antarctic ice; ... a family of gorillas, the male beating his chest, ... an American grizzly bear standing on his hind legs, ten or twelve feet tall, and staring me right in the eye.^[6]:18

His parents helped nurture his growing interest in science by buying him chemistry sets and reading materials.^[8] His interest in space, however, was his primary focus, especially after reading science fiction stories by writers such as Edgar Rice Burroughs, which stirred his imagination about life on other planets, such as Mars. According to biographer Ray Spangenburg, these early years as Sagan tried to understand the mysteries of the planets, became a "driving force in his life, a continual spark to his intellect, and a quest that would never be forgotten."^[7]

Education and scientific career[link]

He attended the University of Chicago, where he participated in the Ryerson Astronomical Society,^[9] received a bachelor of arts in self-proclaimed "nothing" with general and special honors in 1954, a bachelor of science in physics in 1955, and a master of science in physics in 1956 before earning a PhD in astronomy and astrophysics in 1960.^[10][11][12] During his time as an honors program undergraduate, Sagan worked in the laboratory of the geneticist H. J. Muller and wrote a thesis on the origins of life with physical chemist H.C. Urey. From 1960 to 1962 Sagan was a Miller Fellow at the University of California, Berkeley. From 1962 to 1968, he worked at the Smithsonian Astrophysical Observatory in Cambridge, Massachusetts.

Sagan lectured and did research at Harvard University until 1968, when he moved to Cornell University in Ithaca, New York. He became a full Professor at Cornell in 1971, and he directed the Laboratory for Planetary Studies there. From 1972 to 1981, Sagan was the Associate Director of the Center for Radio Physics and Space Research at Cornell.

Sagan was associated with the US space program from its inception. From the 1950s onward, he worked as an advisor to NASA, where one of his duties included briefing the Apollo astronauts before their flights to the Moon. Sagan contributed to many of the robotic spacecraft missions that explored the solar system, arranging experiments on many of the expeditions. He conceived the idea of adding an unalterable and universal message on spacecraft destined to leave the solar system that could potentially be understood by any extraterrestrial intelligence that might find it. Sagan assembled the first physical message that was sent into space: a gold- anodized plaque, attached to the space probe Pioneer 10, launched in 1972. Pioneer 11, also carrying another copy of the plaque, was launched the following year. He continued to refine his designs; the most elaborate message he helped to develop and assemble was the Voyager Golden Record that was sent out with the Voyager space probes in 1977. Sagan often challenged the decisions to fund the Space Shuttle and Space Station at the expense of further robotic missions.^[13]

Sagan taught a course on critical thinking at Cornell University until he died in 1996 from pneumonia, a few months after finding that he was in remission of myelodysplastic syndrome.

Scientific achievements[link]

Sagan's contributions were central to the discovery of the high surface temperatures of the planet Venus. In the early 1960s no one knew for certain the basic conditions of that planet's surface, and Sagan listed the possibilities in a report later depicted for popularization in a Time-Life book, Planets. His own view was that Venus was dry and very hot as opposed to the balmy paradise others had imagined. He had investigated radio emissions from Venus and concluded that there was a surface temperature of 500 °C (900 °F). As a visiting scientist to NASA's Jet Propulsion Laboratory, he contributed to the first Mariner missions to Venus, working on the design and management of the project. Mariner 2 confirmed his conclusions on the surface conditions of Venus in 1962.

Sagan was among the first to hypothesize that Saturn's moon Titan might possess oceans of liquid compounds on its surface and that Jupiter's moon Europa might possess subsurface oceans of water. This would make Europa potentially habitable.^[14] Europa's subsurface ocean of water was later indirectly confirmed by the spacecraft Galileo. The mystery of Titan's reddish haze was also solved with Sagan's help. The reddish haze was revealed to be due to complex organic molecules constantly raining down onto Titan's surface.^[15]

He further contributed insights regarding the atmospheres of Venus and Jupiter as well as seasonal changes on Mars. Sagan established that the atmosphere of Venus is extremely hot and dense with pressures increasing steadily all the way down to the surface. He also perceived global warming as a growing, man-made danger and likened it to the natural development of Venus into a hot, life-hostile planet through a kind of runaway greenhouse effect. Sagan and his Cornell colleague Edwin Ernest Salpeter speculated about life in Jupiter's clouds, given the planet's dense atmospheric composition rich in organic molecules. He studied the observed color variations on Mars' surface and concluded that they were not seasonal or vegetational changes as most believed but shifts in surface dust caused by windstorms.

Sagan is best known, however, for his research on the possibilities of extraterrestrial life, including experimental demonstration of the production of amino acids from basic chemicals by radiation.^[16]

He is also the 1994 recipient of the Public Welfare Medal, the highest award of the National Academy of Sciences for "distinguished contributions in the application of science to the public welfare."^[17] He was denied membership in the Academy, reportedly because his media activities made him unpopular with many other scientists.^[18]

Scientific advocacy[link]

Planetary Society members at the organization's founding. Carl Sagan is seated on the right.

Sagan's ability to convey his ideas allowed many people to better understand the cosmos—simultaneously emphasizing the value and worthiness of the human race, and the relative insignificance of the Earth in comparison to the universe. He delivered the 1977 series of Royal Institution Christmas Lectures in London.^[19] He hosted and, with Ann Druyan, co-wrote and co-produced the highly popular thirteen-part PBS television series Cosmos: A Personal Voyage modeled on Jacob Bronowski's The Ascent of Man.

Cosmos covered a wide range of scientific subjects including the origin of life and a perspective of our place in the universe. The series was first broadcast by the Public Broadcasting Service in 1980, winning an Emmy and a Peabody Award. It has been broadcast in more than 60 countries and seen by over 500 million people,^[3][20] making it the most widely watched PBS program in history.^[21] In addition, Time magazine ran a cover story about Sagan soon after the show broadcast, referring to him as "creator, chief writer and host-narrator of the new public television series Cosmos, [and] takes the controls of his fantasy spaceship."^[22]

Sagan was a proponent of the search for extraterrestrial life. He urged the scientific community to listen with radio telescopes for signals from potential intelligent extraterrestrial life-forms. Sagan was so persuasive that by 1982 he was able to get a petition advocating SETI published in the journal Science and signed by 70 scientists including seven Nobel Prize winners. This was a tremendous increase in the respectability of this controversial field. Sagan also helped Dr. Frank Drake write the Arecibo message, a radio message beamed into space from the Arecibo radio telescope on November 16, 1974, aimed at informing potential extraterrestrials about Earth.

Sagan was chief technology officer of the professional planetary research journal Icarus for twelve years. He co-founded the Planetary Society, the largest space-interest group in the world, with over 100,000 members in more than 149 countries, and was a member of the SETI Institute Board of Trustees. Sagan served as Chairman of the Division for Planetary Science of the American Astronomical Society, as President of the Planetology Section of the American Geophysical Union, and as Chairman of the Astronomy Section of the American Association for the Advancement of Science.

At the height of the Cold War, Sagan became involved in public awareness efforts for the effects of nuclear war when a mathematical climate model suggested that a substantial nuclear exchange could upset the delicate balance of life on Earth. He was one of five authors—the "S" of the "TTAPS" report as the research paper came to be known. He eventually co-authored the scientific paper hypothesizing a global nuclear winter following nuclear war.^[23] He also co-authored the book A Path Where No Man Thought: Nuclear Winter and the End of the Arms Race, a comprehensive examination of the phenomenon of nuclear winter.

Sagan also wrote books to popularize science which reflected and expanded upon some of the themes of A Personal Voyage, and became the best-selling science book ever published in English;^[24] The Dragons of Eden: Speculations on the Evolution of Human Intelligence, which won a Pulitzer Prize; and Broca's Brain: Reflections on the Romance of Science. Sagan also wrote the best-selling science fiction novel Contact in 1985, based on a film treatment he wrote with his wife in 1979, but he did not live to see the book's 1997 motion picture adaptation, which starred Jodie Foster and won the 1998 Hugo Award for Best Dramatic Adaption.

Pale Blue Dot: Earth is a bright pixel when photographed from "Voyager 1" six billion kilometers out (past Pluto). Sagan encouraged NASA to generate this image.

He wrote a sequel to Cosmos, Pale Blue Dot: A Vision of the Human Future in Space, which was selected as a notable book of 1995 by The New York Times. He appeared on PBS' Charlie Rose program in January 1995.^[25] Sagan also wrote an introduction for the bestselling book by Stephen Hawking, A Brief History of Time. Sagan was also known for his popularization of science, his efforts to increase scientific understanding among the general public, and his positions in favor of scientific skepticism and against pseudoscience, such as his debunking of the Betty and Barney Hill abduction. To mark the tenth anniversary of Sagan's death, David Morrison, a former student of Sagan, recalled "Sagan's immense contributions to planetary research, the public understanding of science, and the skeptical movement" in Skeptical Inquirer.^[26]

Sagan hypothesized in January 1991 that enough smoke from the 1991 Kuwaiti oil fires "might get so high as to disrupt agriculture in much of South Asia ..." He later conceded in The Demon-Haunted World that this prediction did not turn out to be correct: "it was pitch black at noon and temperatures dropped 4°–6 °C over the Persian Gulf, but not much smoke reached stratospheric altitudes and Asia was spared."^[27] A 2007 study noted that modern computer models have been applied to the Kuwait oil fires, finding that individual smoke plumes are not able to loft smoke into the stratosphere, but that smoke from fires covering a large area, like some forest fires or the burning of cities that would be expected to follow a nuclear strike, would loft significant amounts of smoke into the stratosphere.^{[28][29][30][31]}

In his later years Sagan advocated the creation of an organized search for near Earth objects that might impact the Earth.^[32] When others suggested creating large nuclear bombs that could be used to alter the orbit of a NEO that was predicted to hit the Earth, Sagan proposed the Deflection Dilemma: If we create the ability to deflect an asteroid away from the Earth, then we also create the ability to deflect an asteroid towards the Earth—providing an evil power with a true doomsday bomb.^[33][34]

Billions and billions[link]

Sagan with a model of the Viking Lander probes which would land on Mars. Sagan examined possible landing sites for Viking along with Mike Carr and Hal Masursky.

From Cosmos and his frequent appearances on The Tonight Show Starring Johnny Carson, Sagan became associated with the catchphrase "billions and billions". Sagan stated that he never actually used the phrase in the Cosmos series.^[35] The closest that he ever came was in the book Cosmos, where he talked of "billions upon billions":^[36]

A galaxy is composed of gas and dust and stars—billions upon billions of stars.

—Carl Sagan, Cosmos, chapter 1, page 3^[37]

However, his frequent use of the word billions, and distinctive delivery emphasizing the "b" (which he did intentionally, in place of more cumbersome alternatives such as "billions with a 'b'", in order to distinguish the word from "millions" in viewers' minds),^[35] made him a favorite target of comic performers, including Johnny Carson,^[38] Gary Kroeger, Mike Myers, Bronson Pinchot, Penn Jillette, Harry Shearer, and others. Frank Zappa satirized the line in the song "Be In My Video", noting as well "atomic light". Sagan took this all in good humor, and his final book was entitled Billions and Billions, which opened with a tongue-in-cheek discussion of this catchphrase, observing that Carson was an amateur astronomer and that Carson's comic caricature often included real science.^[35]

Similarly he is also known for expressing wonderment at the vastness of space and time, as in his phrase "The total number of stars in the Universe is larger than all the grains of sand on all the beaches of the planet Earth."

Sagan units[link]

As a humorous tribute to him, a sagan has been defined as a unit of measurement equal to at least four billion, since the smallest number that may be described as billions and billions must be two billion plus two billion.^[39][40]

Social concerns[link]

Sagan believed that the Drake equation, on substitution of reasonable estimates, suggested that a large number of extraterrestrial civilizations would form, but that the lack of evidence of such civilizations highlighted by the Fermi paradox suggests technological civilizations tend to self-destruct. This stimulated his interest in identifying and publicizing ways that humanity could destroy itself, with the hope of avoiding such a cataclysm and eventually becoming a spacefaring species. Sagan's deep concern regarding the potential destruction of human civilization in a nuclear holocaust was conveyed in a memorable cinematic sequence in the final episode of Cosmos, called "Who Speaks for Earth?" Sagan had already resigned from the Air Force Scientific Advisory Board and voluntarily surrendered his top secret clearance in protest over the Vietnam War.^[41] Following his marriage to his third wife (novelist Ann Druyan) in June 1981, Sagan became more politically active—particularly in opposing escalation of the nuclear arms race under President Ronald Reagan.

In March 1983, Reagan announced the Strategic Defense Initiative—a multi-billion dollar project to develop a comprehensive defense against attack by nuclear missiles, which was quickly dubbed the "Star Wars" program. Sagan spoke out against the project, arguing that it was technically impossible to develop a system with the level of perfection required, and far more expensive to build than for an enemy to defeat through decoys and other means—and that its construction would seriously destabilize the nuclear balance between the United States and the Soviet Union, making further progress toward nuclear disarmament impossible.

When Soviet leader Mikhail Gorbachev declared a unilateral moratorium on the testing of nuclear weapons, which would begin on August 6, 1985—the 40th anniversary of the atomic bombing of Hiroshima—the Reagan administration dismissed the dramatic move as nothing more than propaganda, and refused to follow suit. In response, US anti-nuclear and peace activists staged a series of protest actions at the Nevada Test Site, beginning on Easter Sunday in 1986 and continuing through 1987. Hundreds of people were arrested, including Sagan, who was arrested on two separate occasions as he climbed over a chain-link fence at the test site.^[42]

Personal life and beliefs[link]

Sagan was married three times—in 1957, to biologist Lynn Margulis, mother of Dorion Sagan and Jeremy Sagan; in 1968, to artist Linda Salzman, mother of Nick Sagan; and in 1981, to author Ann Druyan, mother of Alexandra Rachel (Sasha) Sagan and Samuel Democritus Sagan. His marriage to Druyan continued until his death in 1996.

Isaac Asimov described Sagan as one of only two people he ever met whose intellect surpassed his own. The other, he claimed, was the computer scientist and artificial intelligence expert Marvin Minsky.^[43]

Sagan wrote frequently about religion and the relationship between religion and science, expressing his skepticism about the conventional conceptualization of God as a sapient being. For example:

"Some people think God is an outsized, light-skinned male with a long white beard, sitting on a throne somewhere up there in the sky, busily tallying the fall of every sparrow. Others—for example Baruch Spinoza and Albert Einstein—considered God to be essentially the sum total of the physical laws which describe the universe. I do not know of any compelling evidence for anthropomorphic patriarchs controlling human destiny from some hidden celestial vantage point, but it would be madness to deny the existence of physical laws."^[44]

In another description of his view of God, Sagan emphatically writes:

"The idea that God is an oversized white male with a flowing beard who sits in the sky and tallies the fall of every sparrow is ludicrous. But if by God one means the set of physical laws that govern the universe, then clearly there is such a God. This God is emotionally unsatisfying... it does not make much sense to pray to the law of gravity."^[45]

On atheism, Sagan commented in 1981:

"An atheist is someone who is certain that God does not exist, someone who has compelling evidence against the existence of God. I know of no such compelling evidence. Because God can be relegated to remote times and places and to ultimate causes, we would have to know a great deal more about the universe than we do now to be sure that no such God exists. To be certain of the existence of God and to be certain of the nonexistence of God seem to me to be the confident extremes in a subject so riddled with doubt and uncertainty as to inspire very little confidence indeed".^[46]

In reply to a question in 1996 about his religious beliefs, Sagan answered, "I'm agnostic."^[47] Sagan's views on religion have been interpreted as a form of pantheism comparable to Einstein's belief in Spinoza's God.^[48] Sagan maintained that the idea of a creator of the universe was difficult to prove or disprove and that the only conceivable scientific discovery that could challenge it would be an infinitely old universe.^[49] According to his last wife, Ann Druyan, he was not a believer:

When my husband died, because he was so famous and known for not being a believer, many people would come up to me—it still sometimes happens—and ask me if Carl changed at the end and converted to a belief in an afterlife. They also frequently ask me if I think I will see him again. Carl faced his death with unflagging courage and never sought refuge in illusions. The tragedy was that we knew we would never see each other again. I don't ever expect to be reunited with Carl.^[50]

In 2006, Ann Druyan edited Sagan's 1985 Glasgow Gifford Lectures in Natural Theology into a book, The Varieties of Scientific Experience: A Personal View of the Search for God, in which he elaborates on his views of divinity in the natural world.

Carl Sagan (center) speaks with CDC employees in 1988.

Sagan is also widely regarded as a freethinker or skeptic; one of his most famous quotations, in Cosmos, was, "Extraordinary claims require extraordinary evidence"^[51] (called the "Sagan Standard" by some^[52]). This was based on a nearly identical statement by fellow founder of the Committee for the Scientific Investigation of Claims of the Paranormal, Marcello Truzzi, "An extraordinary claim requires extraordinary proof."^[53][54] This idea originated with Pierre-Simon Laplace (1749–1827), a French mathematician and astronomer who said, "The weight of evidence for an extraordinary claim must be proportioned to its strangeness."^[55]

Late in his life, Sagan's books elaborated on his skeptical, naturalistic view of the world. In The Demon-Haunted World: Science as a Candle in the Dark, he presented tools for testing arguments and detecting fallacious or fraudulent ones, essentially advocating wide use of critical thinking and the scientific method. The compilation Billions and Billions: Thoughts on Life and Death at the Brink of the Millennium, published in 1997 after Sagan's death, contains essays written by Sagan, such as his views on abortion, and his widow Ann Druyan's account of his death as a skeptic, agnostic, and freethinker.

Sagan warned against humans' tendency towards anthropocentrism. He was the faculty adviser for the Cornell Students for the Ethical Treatment of Animals. In the Cosmos chapter "Blues For a Red Planet", Sagan wrote, "If there is life on Mars, I believe we should do nothing with Mars. Mars then belongs to the Martians, even if the Martians are only microbes."^[56]

Sagan was a user and advocate of marijuana. Under the pseudonym "Mr. X", he contributed an essay about smoking cannabis to the 1971 book Marihuana Reconsidered.^[57][58] The essay explained that marijuana use had helped to inspire some of Sagan's works and enhance sensual and intellectual experiences. After Sagan's death, his friend Lester Grinspoon disclosed this information to Sagan's biographer, Keay Davidson. The publishing of the biography, Carl Sagan: A Life, in 1999 brought media attention to this aspect of Sagan's life.^[59][60][61] Not long after his death, widow Ann Druyan had gone on to preside over the board of directors of NORML, a foundation dedicated to reforming cannabis laws.^[62]

In 1994, engineers at Apple Computer code-named the Power Macintosh 7100 "Carl Sagan" in the hope that Apple would make "billions and billions" with the sale of the PowerMac 7100.^[4] The name was only used internally, but Sagan was concerned that it would become a product endorsement and sent Apple a cease and desist letter. Apple complied, but engineers retaliated by changing the internal codename to "BHA" for "Butt-Head Astronomer".^[63][64] Sagan then sued Apple for libel, a form of defamation, in federal court. The court granted Apple's motion to dismiss Sagan's claims and opined in dicta that a reader aware of the context would understand Apple was "clearly attempting to retaliate in a humorous and satirical way", and that "It strains reason to conclude that Defendant was attempting to criticize Plaintiff's reputation or competency as an astronomer. One does not seriously attack the expertise of a scientist using the undefined phrase 'butt-head'."^[63][65] Sagan then sued for Apple's original use of his name and likeness, but again lost.^[66] Sagan appealed the ruling.^[66] In November 1995, an out of court settlement was reached and Apple's office of trademarks and patents released a conciliatory statement that "Apple has always had great respect for Dr. Sagan. It was never Apple's intention to cause Dr. Sagan or his family any embarrassment or concern."^[67]

Sagan briefly served as an adviser on Stanley Kubrick's film 2001: A Space Odyssey.^[6] Sagan proposed that the film would suggest, rather than depict, extraterrestrial superintelligence.^[68]

Sagan and UFOs[link]

Sagan had some interest in UFO reports from at least August 3, 1952 when he wrote a letter to U.S. Secretary of State Dean Acheson to ask how the U.S. would respond if flying saucers turned out to be extraterrestrial.^[69] He later had several conversations on the subject in 1964 with Jacques Vallee.^[70] Though quite skeptical of any extraordinary answer to the UFO question, Sagan thought scientists should study the phenomenon, at least because there was widespread public interest in UFO reports.

Stuart Appelle notes that Sagan "wrote frequently on what he perceived as the logical and empirical fallacies regarding UFOs and the abduction experience. Sagan rejected an extraterrestrial explanation for the phenomenon but felt there were both empirical and pedagogical benefits for examining UFO reports and that the subject was, therefore, a legitimate topic of study."^[71]

In 1966, Sagan was a member of the Ad Hoc Committee to Review Project Blue Book, the U.S. Air Force's UFO investigation project. The committee concluded Blue Book had been lacking as a scientific study, and recommended a university-based project to give the UFO phenomenon closer scientific scrutiny. The result was the Condon Committee (1966–1968), led by physicist Edward Condon, and in their final report they formally concluded that UFOs, regardless of what any of them actually were, did not behave in a manner consistent with a threat to national security.

Ron Westrum writes that "The high point of Sagan's treatment of the UFO question was the AAAS's symposium in 1969. A wide range of educated opinions on the subject were offered by participants, including not only proponents such as James McDonald and J. Allen Hynek but also skeptics like astronomers William Hartmann and Donald Menzel. The roster of speakers was balanced, and it is to Sagan's credit that this event was presented in spite of pressure from Edward Condon".^[70] With physicist Thornton Page, Sagan edited the lectures and discussions given at the symposium; these were published in 1972 as UFOs: A Scientific Debate. Some of Sagan's many books examine UFOs (as did one episode of Cosmos) and he claimed a religious undercurrent to the phenomenon.

Sagan again revealed his views on interstellar travel in his 1980 Cosmos series. In one of his last written works, Sagan argued that the chances of extraterrestrial spacecraft visiting Earth are vanishingly small. However, Sagan did think it plausible that Cold War concerns contributed to governments misleading their citizens about UFOs, and that "some UFO reports and analyses, and perhaps voluminous files, have been made inaccessible to the public which pays the bills ... It's time for the files to be declassified and made generally available." He cautioned against jumping to conclusions about suppressed UFO data and stressed that there was no strong evidence that aliens were visiting the Earth either in the past or present.^[72]

Death[link]

Stone dedicated to Carl Sagan in the Celebrity Path of the Brooklyn Botanic Garden

After a long and difficult fight with myelodysplasia, which included three bone marrow transplants, Sagan died of pneumonia at the age of 62 at the Fred Hutchinson Cancer Research Center in Seattle, Washington, on December 20, 1996.^[73] He was buried at Lakeview Cemetery in Ithaca, New York.^[74]

Posthumous recognition[link]

The 1997 movie Contact, based on Sagan's novel of the same name and finished after his death, ends with the dedication "For Carl".

In 1997, the Sagan Planet Walk was opened in Ithaca, New York. It is a walking scale model of the solar system, extending 1.2 km from the center of The Commons in downtown Ithaca to the Sciencenter, a hands-on museum. The exhibition was created in memory of Carl Sagan, who was an Ithaca resident and Cornell Professor. Professor Sagan had been a founding member of the museum's advisory board.^[75]

The landing site of the unmanned Mars Pathfinder spacecraft was renamed the Carl Sagan Memorial Station on July 5, 1997. Asteroid 2709 Sagan is named in his honor.

Sagan's son, Nick Sagan, wrote several episodes in the Star Trek franchise. In an episode of Star Trek: Enterprise entitled "Terra Prime", a quick shot is shown of the relic rover Sojourner, part of the Mars Pathfinder mission, placed by a historical marker at Carl Sagan Memorial Station on the Martian surface. The marker displays a quote from Sagan: "Whatever the reason you're on Mars, I'm glad you're there, and I wish I was with you." Sagan's student Steve Squyres led the team that landed the Spirit Rover and Opportunity Rover successfully on Mars in 2004.

On November 9, 2001, on what would have been Sagan's 67th birthday, the NASA Ames Research Center dedicated the site for the Carl Sagan Center for the Study of Life in the Cosmos. "Carl was an incredible visionary, and now his legacy can be preserved and advanced by a 21st century research and education laboratory committed to enhancing our understanding of life in the universe and furthering the cause of space exploration for all time", said NASA Administrator Daniel Goldin. Ann Druyan was at the Center as it opened its doors on October 22, 2006.

Sagan has at least three awards named in his honor:

• The Carl Sagan Memorial Award presented jointly since 1997 by the American Astronomical Society (AAS) and the Planetary Society,
• The Carl Sagan Medal for Excellence in Public Communication in Planetary Science presented since 1998 by the American Astronomical Society's Division for Planetary Sciences (AAS/DPS) for outstanding communication by an active planetary scientist to the general public—Carl Sagan was one of the original organizing committee members of the DPS, and
• The Carl Sagan Award for Public Understanding of Science presented by the Council of Scientific Society Presidents (CSSP)—Sagan was the first recipient of the CSSP award in 1993.^[76]

In 2006, the Carl Sagan Medal was awarded to astrobiologist and author David Grinspoon, the son of Sagan's friend Lester Grinspoon.

On December 20, 2006, the tenth anniversary of Sagan's death, a blogger, Joel Schlosberg, organized a Carl Sagan "blog-a-thon" to commemorate Sagan's death, and the idea was supported by Nick Sagan.^[77] Many members of the blogging community participated.

August 2007 the Independent Investigative Group IIG awarded Sagan posthumously a Lifetime Achievement Award. This honor has also been awarded to Harry Houdini and James Randi.^[78]

Beginning in 2009, a musical project known as Symphony of Science sampled several excerpts of Sagan from his series Cosmos and remixed them to electronic music. To date, the videos have received over twenty-million views worldwide on the popular user generated website Youtube, and have exposed a new generation to the interconnected grandeur of the universe as Sagan described them in his documentary series.^[79]

Awards and honors[link]

NASA Distinguished Public Service Medal

• Annual Award for Television Excellence—1981—Ohio State University—PBS series Cosmos
• Apollo Achievement Award—National Aeronautics and Space Administration
• NASA Distinguished Public Service Medal—National Aeronautics and Space Administration (twice)
• Emmy—Outstanding Individual Achievement—1981—PBS series Cosmos
• Emmy—Outstanding Informational Series—1981—PBS series Cosmos
• Exceptional Scientific Achievement Medal—National Aeronautics and Space Administration
• Helen Caldicott Leadership Award – Awarded by Women's Action for Nuclear Disarmament
• Hugo Award—1981—Cosmos
• Humanist of the Year—1981—Awarded by the American Humanist Association
• In Praise of Reason Award—1987—Committee for the Scientific Investigation of Claims of the Paranormal
• Isaac Asimov Award—1994—Committee for the Scientific Investigation of Claims of the Paranormal
• John F. Kennedy Astronautics Award—American Astronautical Society
• John W. Campbell Memorial Award—1974—The Cosmic Connection: An Extraterrestrial Perspective
• Joseph Priestley Award—"For distinguished contributions to the welfare of mankind"
• Klumpke-Roberts Award of the Astronomical Society of the Pacific—1974
• Konstantin Tsiolkovsky Medal—Awarded by the Soviet Cosmonauts Federation
• Locus Award 1986—Contact
• Lowell Thomas Award—Explorers Club—75th Anniversary
• Masursky Award—American Astronomical Society
• Miller Research Fellowship—Miller Institute (1960–1962)
• Oersted Medal—1990—American Association of Physics Teachers
• Peabody Award—1980—PBS series Cosmos
• Prix Galbert—The international prize of Astronautics
• Public Welfare Medal—1994—National Academy of Sciences^[80]
• Pulitzer Prize for General Non-Fiction—1978—The Dragons of Eden
• SF Chronicle Award—1998—Contact
• Named the "99th Greatest American" on the June 5, 2005, Greatest American show on the Discovery Channel
• Named an honorary member of the Demosthenian Literary Society on November 10, 2011
• 2009 New Jersey Hall of Fame inductee.^[81]