1.
Hubble Space Telescope
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The Hubble Space Telescope is a space telescope that was launched into low Earth orbit in 1990 and remains in operation. Although not the first space telescope, Hubble is one of the largest and most versatile, with a 2. 4-meter mirror, Hubbles four main instruments observe in the near ultraviolet, visible, and near infrared spectra. Hubbles orbit outside the distortion of Earths atmosphere allows it to take extremely high-resolution images, Hubble has recorded some of the most detailed visible light images ever, allowing a deep view into space and time. Many Hubble observations have led to breakthroughs in astrophysics, such as determining the rate of expansion of the universe. The HST was built by the United States space agency NASA, the Space Telescope Science Institute selects Hubbles targets and processes the resulting data, while the Goddard Space Flight Center controls the spacecraft. Space telescopes were proposed as early as 1923, Hubble was funded in the 1970s, with a proposed launch in 1983, but the project was beset by technical delays, budget problems, and the Challenger disaster. When finally launched in 1990, Hubbles main mirror was found to have been ground incorrectly, the optics were corrected to their intended quality by a servicing mission in 1993. Hubble is the telescope designed to be serviced in space by astronauts. After launch by Space Shuttle Discovery in 1990, five subsequent Space Shuttle missions repaired, upgraded, the fifth mission was canceled on safety grounds following the Columbia disaster. However, after spirited public discussion, NASA administrator Mike Griffin approved the fifth servicing mission, the telescope is operating as of 2017, and could last until 2030–2040. Its scientific successor, the James Webb Space Telescope, is scheduled for launch in 2018, the history of the Hubble Space Telescope can be traced back as far as 1946, to the astronomer Lyman Spitzers paper Astronomical advantages of an extraterrestrial observatory. In it, he discussed the two advantages that a space-based observatory would have over ground-based telescopes. First, the resolution would be limited only by diffraction, rather than by the turbulence in the atmosphere. Second, a telescope could observe infrared and ultraviolet light. Spitzer devoted much of his career to pushing for the development of a space telescope, space-based astronomy had begun on a very small scale following World War II, as scientists made use of developments that had taken place in rocket technology. An orbiting solar telescope was launched in 1962 by the United Kingdom as part of the Ariel space program, oAO-1s battery failed after three days, terminating the mission. It was followed by OAO-2, which carried out observations of stars and galaxies from its launch in 1968 until 1972. The continuing success of the OAO program encouraged increasingly strong consensus within the community that the LST should be a major goal
2.
Constellation
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A constellation is formally defined as a region of the celestial sphere, with boundaries laid down by the International Astronomical Union. The constellation areas mostly had their origins in Western-traditional patterns of stars from which the constellations take their names, in 1922, the International Astronomical Union officially recognized the 88 modern constellations, which cover the entire sky. They began as the 48 classical Greek constellations laid down by Ptolemy in the Almagest, Constellations in the far southern sky are late 16th- and mid 18th-century constructions. 12 of the 88 constellations compose the zodiac signs, though the positions of the constellations only loosely match the dates assigned to them in astrology. The term constellation can refer to the stars within the boundaries of that constellation. Notable groupings of stars that do not form a constellation are called asterisms, when astronomers say something is “in” a given constellation they mean it is within those official boundaries. Any given point in a coordinate system can unambiguously be assigned to a single constellation. Many astronomical naming systems give the constellation in which an object is found along with a designation in order to convey a rough idea in which part of the sky it is located. For example, the Flamsteed designation for bright stars consists of a number, the word constellation seems to come from the Late Latin term cōnstellātiō, which can be translated as set of stars, and came into use in English during the 14th century. It also denotes 88 named groups of stars in the shape of stellar-patterns, the Ancient Greek word for constellation was ἄστρον. Colloquial usage does not draw a distinction between constellation in the sense of an asterism and constellation in the sense of an area surrounding an asterism. The modern system of constellations used in astronomy employs the latter concept, the term circumpolar constellation is used for any constellation that, from a particular latitude on Earth, never sets below the horizon. From the North Pole or South Pole, all constellations south or north of the equator are circumpolar constellations. In the equatorial or temperate latitudes, the term equatorial constellation has sometimes been used for constellations that lie to the opposite the circumpolar constellations. They generally include all constellations that intersect the celestial equator or part of the zodiac, usually the only thing the stars in a constellation have in common is that they appear near each other in the sky when viewed from the Earth. In galactic space, the stars of a constellation usually lie at a variety of distances, since stars also travel on their own orbits through the Milky Way, the star patterns of the constellations change slowly over time. After tens to hundreds of thousands of years, their familiar outlines will become unrecognisable, the terms chosen for the constellation themselves, together with the appearance of a constellation, may reveal where and when its constellation makers lived. The earliest direct evidence for the constellations comes from inscribed stones and it seems that the bulk of the Mesopotamian constellations were created within a relatively short interval from around 1300 to 1000 BC
3.
Cosmic distance ladder
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The cosmic distance ladder is the succession of methods by which astronomers determine the distances to celestial objects. A real direct distance measurement of an object is possible only for those objects that are close enough to Earth. The techniques for determining distances to more distant objects are all based on various measured correlations between methods that work at distances and methods that work at larger distances. Several methods rely on a candle, which is an astronomical object that has a known luminosity. The ladder analogy arises because no single technique can measure distances at all ranges encountered in astronomy, instead, one method can be used to measure nearby distances, a second can be used to measure nearby to intermediate distances, and so on. Each rung of the ladder provides information that can be used to determine the distances at the next higher rung, at the base of the ladder are fundamental distance measurements, in which distances are determined directly, with no physical assumptions about the nature of the object in question. The precise measurement of stellar positions is part of the discipline of astrometry, direct distance measurements are based upon the astronomical unit, which is the distance between the Earth and the Sun. Historically, observations of transits of Venus were crucial in determining the AU, in the first half of the 20th century, observations of asteroids were also important. Keplers laws provide precise ratios of the sizes of the orbits of objects orbiting the Sun, radar is used to measure the distance between the orbits of the Earth and of a second body. From that measurement and the ratio of the two sizes, the size of Earths orbit is calculated. The Earths orbit is known with a precision of a few meters, the most important fundamental distance measurements come from trigonometric parallax. As the Earth orbits the Sun, the position of stars will appear to shift slightly against the more distant background. These shifts are angles in a triangle, with 2 AU making the base leg of the triangle. The amount of shift is small, measuring 1 arcsecond for an object at the 1 parsec distance of the nearest stars. Astronomers usually express distances in units of parsecs, light-years are used in popular media, because parallax becomes smaller for a greater stellar distance, useful distances can be measured only for stars whose parallax is larger than a few times the precision of the measurement. Parallax measurements typically have an accuracy measured in milliarcseconds, the Hubble telescope WFC3 now has the potential to provide a precision of 20 to 40 microarcseconds, enabling reliable distance measurements up to 5,000 parsecs for small numbers of stars. By the early 2020s, the GAIA space mission will provide similarly accurate distances to all bright stars. Stars have a velocity relative to the Sun that causes proper motion, for a group of stars with the same spectral class and a similar magnitude range, a mean parallax can be derived from statistical analysis of the proper motions relative to their radial velocities
4.
Galaxy morphological classification
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Galaxy morphological classification is a system used by astronomers to divide galaxies into groups based on their visual appearance. The Hubble sequence is a classification scheme for galaxies invented by Edwin Hubble in 1926. It is often known colloquially as the “Hubble tuning-fork” because of the shape in which it is traditionally represented, Hubble’s scheme divides galaxies into three broad classes based on their visual appearance, Elliptical galaxies have smooth, featureless light distributions and appear as ellipses in images. They are denoted by the letter E, followed by an integer n representing their degree of ellipticity on the sky. Spiral galaxies consist of a disk, with stars forming a spiral structure, and a central concentration of stars known as the bulge. They are given the symbol S, roughly half of all spirals are also observed to have a bar-like structure, extending from the central bulge. These barred spirals are given the symbol SB and these broad classes can be extended to enable finer distinctions of appearance and to encompass other types of galaxies, such as irregular galaxies, which have no obvious regular structure. The Hubble sequence is represented in the form of a two-pronged fork, with the ellipticals on the left. Lenticular galaxies are placed between the ellipticals and the spirals, at the point where the two meet the “handle”. To this day, the Hubble sequence is the most commonly used system for classifying galaxies, the de Vaucouleurs system for classifying galaxies is a widely used extension to the Hubble sequence, first described by Gérard de Vaucouleurs in 1959. In particular, he argued that rings and lenses are important structural components of spiral galaxies, the de Vaucouleurs system retains Hubble’s basic division of galaxies into ellipticals, lenticulars, spirals and irregulars. For example, a barred spiral galaxy with loosely wound arms. Visually, the de Vaucouleurs system can be represented as a version of Hubble’s tuning fork, with stage on the x-axis, family on the y-axis. De Vaucouleurs also assigned numerical values to each class of galaxy in his scheme, values of the numerical Hubble stage T run from −6 to +10, with negative numbers corresponding to early-type galaxies and positive numbers to late types. Elliptical galaxies are divided into three stages, compact ellipticals, normal ellipticals and late types, lenticulars are similarly subdivided into early, intermediate and late types. Irregular galaxies can be of type magellanic irregulars or compact, the use of numerical stages allows for more quantitative studies of galaxy morphology. Created by American astronomer William Wilson Morgan, together with Philip Keenan, Morgan developed the MK system for the classification of stars through their spectra. The Yerkes scheme uses the spectra of stars in the galaxy, the shape, real and apparent, thus, for example, the Andromeda Galaxy is classified as kS5. H
5.
Atlas of Peculiar Galaxies
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The Atlas of Peculiar Galaxies is a catalog of peculiar galaxies produced by Halton Arp in 1966. A total of 338 galaxies are presented in the atlas, which was published in 1966 by the California Institute of Technology. The primary goal of the catalog was to present photographs of examples of the different kinds of structures found among nearby galaxies. Arp realized that the reason why galaxies formed into spiral or elliptical shapes was not well understood and he perceived peculiar galaxies as small experiments that astronomers could use to understand the physical processes that distort spiral or elliptical galaxies. With this atlas, astronomers had a sample of galaxies that they could study in more detail. The atlas does not present an overview of every peculiar galaxy in the sky. Because little was known at the time of publication about the processes that caused the different shapes. Objects 1–101 are individual peculiar spiral galaxies or spiral galaxies that apparently have small companions, objects 102–145 are elliptical and elliptical-like galaxies. Individual or groups of galaxies with neither elliptical nor spiral shapes are listed as objects 146–268, finally, objects that simply do not fit into any of the above categories are listed as objects 332–338. Most objects are best known by their other designations, but a few galaxies are best known by their Arp numbers, today, the physical processes that lead to the peculiarities seen in the Arp atlas are well understood. A large number of the objects are interacting galaxies, including M51, Arp 220, a few of the galaxies are simply dwarf galaxies that do not have enough mass to produce enough gravity to allow the galaxies to form any cohesive structure. NGC1569 is an example of one of the galaxies in the atlas. A few other galaxies are radio galaxies and these objects contain active galactic nuclei that produce powerful jets of gas called radio jets. The atlas includes the nearby radio galaxies M87 and Centaurus A and these are mostly dwarf galaxies or poorly defined spiral galaxies that have low surface brightnesses. Low surface brightness galaxies are quite common. The exception is NGC2857, which is an Sc spiral galaxy and this category contains spiral galaxies with arms that split into two separate parts. This category contains spiral galaxies with arms that appear to be segmented, some spiral arm segments may appear detached because dust lanes in the spiral arms obscure the arms starlight. Other spiral arms may appear segmented because of the presence of star clusters in the spiral arms
6.
Galaxy
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A galaxy is a gravitationally bound system of stars, stellar remnants, interstellar gas, dust, and dark matter. The word galaxy is derived from the Greek galaxias, literally milky, Galaxies range in size from dwarfs with just a few billion stars to giants with one hundred trillion stars, each orbiting its galaxys center of mass. Galaxies are categorized according to their morphology as elliptical, spiral. Many galaxies are thought to have holes at their active centers. The Milky Ways central black hole, known as Sagittarius A*, has a four million times greater than the Sun. Recent estimates of the number of galaxies in the observable universe range from 200 billion to 2 trillion or more, most of the galaxies are 1,000 to 100,000 parsecs in diameter and separated by distances on the order of millions of parsecs. The space between galaxies is filled with a gas having an average density of less than one atom per cubic meter. The majority of galaxies are organized into groups, clusters. At the largest scale, these associations are generally arranged into sheets and filaments surrounded by immense voids. In Greek mythology, Zeus places his son born by a mortal woman, the infant Heracles, on Heras breast while she is asleep so that the baby will drink her divine milk and will thus become immortal. Hera wakes up while breastfeeding and then realizes she is nursing a baby, she pushes the baby away, some of her milk spills and. In the astronomical literature, the capitalized word Galaxy is often used to refer to our galaxy, the Milky Way, to distinguish it from the other galaxies in our universe. The English term Milky Way can be traced back to a story by Chaucer c. 1380, See yonder, lo, the Galaxyë Which men clepeth the Milky Wey, For hit is whyt. However, the word Universe was later understood to mean the entirety of existence, so this expression fell into disuse and the objects instead became known as galaxies. Tens of thousands of galaxies have been catalogued, but only a few have well-established names, such as the Andromeda Galaxy, the Magellanic Clouds, the Whirlpool Galaxy, and the Sombrero Galaxy. Astronomers work with numbers from certain catalogues, such as the Messier catalogue, the NGC, the IC, the CGCG, all of the well-known galaxies appear in one or more of these catalogues but each time under a different number. For example, Messier 109 is a galaxy having the number 109 in the catalogue of Messier, but also codes NGC3992, UGC6937, CGCG 269-023, MCG +09-20-044. One of the arguments to do so is that these impressive objects deserve better than uninspired codes, for instance, Bodifee and Berger propose the informal, descriptive name Callimorphus Ursae Majoris for the well-formed barred galaxy Messier 109 in Ursa Major
7.
Dwight D. Eisenhower
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Dwight David Ike Eisenhower was an American politician and Army general who served as the 34th President of the United States from 1953 until 1961. He was a general in the United States Army during World War II. He was responsible for planning and supervising the invasion of North Africa in Operation Torch in 1942–43, in 1951, he became the first Supreme Commander of NATO. Eisenhower was of mostly Pennsylvania Dutch ancestry and was raised in a family in Kansas by parents with a strong religious background. He graduated from West Point in 1915 and later married Mamie Doud, after World War II, Eisenhower served as Army Chief of Staff under President Harry S. Truman and then accepted the post of President at Columbia University. Eisenhower entered the 1952 presidential race as a Republican to counter the non-interventionism of Senator Robert A. Taft, campaigning against communism, Korea and he won in a landslide, defeating Democratic candidate Adlai Stevenson and temporarily upending the New Deal Coalition. Eisenhower was the first U. S. president to be constitutionally term-limited under the 22nd Amendment, Eisenhowers main goals in office were to keep pressure on the Soviet Union and reduce federal deficits. He ordered coups in Iran and Guatemala, Eisenhower gave major aid to help the French in the First Indochina War, and after the French were defeated he gave strong financial support to the new state of South Vietnam. Congress agreed to his request in 1955 for the Formosa Resolution, after the Soviet Union launched Sputnik in 1957, Eisenhower authorized the establishment of NASA, which led to the space race. During the Suez Crisis of 1956, Eisenhower condemned the Israeli, British and French invasion of Egypt and he also condemned the Soviet invasion during the Hungarian Revolution of 1956 but took no action. Eisenhower sent 15,000 U. S. troops to Lebanon to prevent the government from falling to a Nasser-inspired revolution during the 1958 Lebanon crisis. Near the end of his term, his efforts to set up a meeting with the Soviets collapsed because of the U-2 incident. On the domestic front, he covertly opposed Joseph McCarthy and contributed to the end of McCarthyism by openly invoking executive privilege and he otherwise left most political activity to his Vice President, Richard Nixon. Eisenhower was a conservative who continued New Deal agencies and expanded Social Security. Eisenhowers two terms saw considerable economic prosperity except for a decline in 1958. Voted Gallups most admired man twelve times, he achieved widespread popular esteem both in and out of office, since the late 20th century, consensus among Western scholars has consistently held Eisenhower as one of the greatest U. S. Presidents. The Eisenhauer family migrated from Karlsbrunn in the Saarland, to North America, first settling in York, Pennsylvania, in 1741, accounts vary as to how and when the German name Eisenhauer was anglicized to Eisenhower. Eisenhowers Pennsylvania Dutch ancestors, who were farmers, included Hans Nikolaus Eisenhauer of Karlsbrunn
8.
Nuclear power
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Nuclear power is the use of nuclear reactions that release nuclear energy to generate heat, which most frequently is then used in steam turbines to produce electricity in a nuclear power plant. The term includes nuclear fission, nuclear decay and nuclear fusion, since all electricity supplying technologies use cement, etc. during construction, emissions are yet to be brought to zero. Each result is contrasted with coal and fossil gas at 820 and 490 g CO2 eq/kWh, there is a social debate about nuclear power. Proponents, such as the World Nuclear Association and Environmentalists for Nuclear Energy, contend that nuclear power is a safe, opponents, such as Greenpeace International and NIRS, contend that nuclear power poses many threats to people and the environment. These include the Chernobyl disaster which occurred in 1986, the Fukushima Daiichi nuclear disaster, there have also been some nuclear submarine accidents. Energy production from coal, petroleum, natural gas and hydroelectricity has caused a number of fatalities per unit of energy generated due to air pollution. In 2015, Ten new reactors were connected to the grid, seven reactors were permanently shut down. 441 reactors had a net capacity of 382,855 megawatts of electricity. 67 new nuclear reactors were under construction, Most of the new activity is in China where there is an urgent need to control pollution from coal plants. In October 2016, Watts Bar 2 became the first new United States reactor to enter commercial operation since 1996. The same year, his doctoral student James Chadwick discovered the neutron, further work by Enrico Fermi in the 1930s focused on using slow neutrons to increase the effectiveness of induced radioactivity. Experiments bombarding uranium with neutrons led Fermi to believe he had created a new, transuranic element and they determined that the relatively tiny neutron split the nucleus of the massive uranium atoms into two roughly equal pieces, contradicting Fermi. Numerous scientists, including Leó Szilárd, who was one of the first, recognized that if fission reactions released additional neutrons, a self-sustaining nuclear chain reaction could result. In the United States, where Fermi and Szilárd had both emigrated, this led to the creation of the first man-made reactor, known as Chicago Pile-1, which achieved criticality on December 2,1942. In 1945, the pocketbook The Atomic Age heralded the untapped atomic power in everyday objects and depicted a future where fossil fuels would go unused. One science writer, David Dietz, wrote that instead of filling the gas tank of a car two or three times a week, people travel for a year on a pellet of atomic energy the size of a vitamin pill. The United Kingdom, Canada, and the USSR proceeded over the course of the late 1940s, electricity was generated for the first time by a nuclear reactor on December 20,1951, at the EBR-I experimental station near Arco, Idaho, which initially produced about 100 kW. Work was also researched in the US on nuclear marine propulsion
9.
Nuclear weapon
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A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission or a combination of fission and fusion. Both reactions release vast quantities of energy from small amounts of matter. The first test of a bomb released the same amount of energy as approximately 20,000 tons of TNT. The first thermonuclear bomb test released the same amount of energy as approximately 10 million tons of TNT, a thermonuclear weapon weighing little more than 2,400 pounds can produce an explosive force comparable to the detonation of more than 1.2 million tons of TNT. A nuclear device no larger than traditional bombs can devastate a city by blast, fire. Nuclear weapons are considered weapons of destruction, and their use. Nuclear weapons have been used twice in nuclear warfare, both times by the United States against Japan near the end of World War II, the bombings resulted in the deaths of approximately 200,000 civilians and military personnel from acute injuries sustained from the explosions. The ethics of the bombings and their role in Japans surrender remain the subject of scholarly, since the atomic bombings of Hiroshima and Nagasaki, nuclear weapons have been detonated on over two thousand occasions for the purposes of testing and demonstration. Only a few nations possess such weapons or are suspected of seeking them, israel is also believed to possess nuclear weapons, though in a policy of deliberate ambiguity, it does not acknowledge having them. Germany, Italy, Turkey, Belgium and the Netherlands are nuclear weapons sharing states, south Africa is the only country to have independently developed and then renounced and dismantled its nuclear weapons. Modernisation of weapons continues to occur, all existing nuclear weapons derive some of their explosive energy from nuclear fission reactions. Weapons whose explosive output is exclusively from fission reactions are commonly referred to as bombs or atom bombs. This has long noted as something of a misnomer, as their energy comes from the nucleus of the atom. The latter approach is considered more sophisticated than the former and only the approach can be used if the fissile material is plutonium. A major challenge in all nuclear weapon designs is to ensure that a significant fraction of the fuel is consumed before the weapon destroys itself. The amount of energy released by fission bombs can range from the equivalent of just under a ton to upwards of 500,000 tons of TNT, all fission reactions necessarily generate fission products, the radioactive remains of the atomic nuclei split by the fission reactions. Many fission products are highly radioactive or moderately radioactive. Fission products are the radioactive component of nuclear fallout
10.
Black hole
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A black hole is a region of spacetime exhibiting such strong gravitational effects that nothing—not even particles and electromagnetic radiation such as light—can escape from inside it. The theory of relativity predicts that a sufficiently compact mass can deform spacetime to form a black hole. The boundary of the region from which no escape is possible is called the event horizon, although the event horizon has an enormous effect on the fate and circumstances of an object crossing it, no locally detectable features appear to be observed. In many ways a black hole acts like a black body. Moreover, quantum theory in curved spacetime predicts that event horizons emit Hawking radiation. This temperature is on the order of billionths of a kelvin for black holes of stellar mass, objects whose gravitational fields are too strong for light to escape were first considered in the 18th century by John Michell and Pierre-Simon Laplace. Black holes were considered a mathematical curiosity, it was during the 1960s that theoretical work showed they were a generic prediction of general relativity. The discovery of neutron stars sparked interest in gravitationally collapsed compact objects as a possible astrophysical reality, black holes of stellar mass are expected to form when very massive stars collapse at the end of their life cycle. After a black hole has formed, it can continue to grow by absorbing mass from its surroundings, by absorbing other stars and merging with other black holes, supermassive black holes of millions of solar masses may form. There is general consensus that supermassive black holes exist in the centers of most galaxies, despite its invisible interior, the presence of a black hole can be inferred through its interaction with other matter and with electromagnetic radiation such as visible light. Matter that falls onto a black hole can form an accretion disk heated by friction. If there are other stars orbiting a black hole, their orbits can be used to determine the black holes mass, such observations can be used to exclude possible alternatives such as neutron stars.3 million solar masses. On 15 June 2016, a detection of a gravitational wave event from colliding black holes was announced. The idea of a body so massive that light could not escape was briefly proposed by astronomical pioneer John Michell in a letter published in 1783-4. Michell correctly noted that such supermassive but non-radiating bodies might be detectable through their effects on nearby visible bodies. In 1915, Albert Einstein developed his theory of general relativity, only a few months later, Karl Schwarzschild found a solution to the Einstein field equations, which describes the gravitational field of a point mass and a spherical mass. A few months after Schwarzschild, Johannes Droste, a student of Hendrik Lorentz, independently gave the solution for the point mass. This solution had a peculiar behaviour at what is now called the Schwarzschild radius, the nature of this surface was not quite understood at the time
11.
MPG/ESO telescope
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The MPG/ESO telescope is a 2. 2-metre ground-based telescope at the European Southern Observatory in La Silla, Chile. It was built by Zeiss and has been operating since 1984 and it was on indefinite loan to the European Southern Observatory from the Max Planck Institute for Astronomy. In October 2013 it was returned to the MPIA, telescope time is shared between MPIA and MPE observing programmes, while the operation and maintenance of the telescope are ESOs responsibility. In November 2010 it was used to discover HIP13044 b, marking the first time a planetary system in a stellar stream of extragalactic origin has been detected
12.
European Southern Observatory
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The European Southern Observatory is a 16-nation intergovernmental research organization for ground-based astronomy. Created in 1962, ESO has provided astronomers with state-of-the-art research facilities, the organisation employs about 730 staff members and receives annual member state contributions of approximately €131 million. Its observatories are located in northern Chile, ESO has built and operated some of the largest and most technologically advanced telescopes. The Atacama Large Millimeter Array observes the universe in the millimetre and submillimetre wavelength ranges and it was completed in March 2013 in an international collaboration by Europe, North America, East Asia and Chile. Currently under construction is the European Extremely Large Telescope and it will use a 39. 3-metre-diameter segmented mirror, and become the worlds largest optical reflecting telescope when operational in 2024. ESOs observing facilities have made discoveries and produced several astronomical catalogues. Its findings include the discovery of the most distant gamma-ray burst, in 2004, the VLT allowed astronomers to obtain the first picture of an extrasolar planet orbiting a brown dwarf 173 light-years away. The idea that European astronomers should establish a large observatory was broached by Walter Baade. It was pursued by Oort, who gathered a group of astronomers in Leiden to consider it on June 21 that year, immediately thereafter, the subject was further discussed at the Groningen conference in the Netherlands. On January 26,1954, an ESO declaration was signed by astronomers from six European countries expressing the wish that a joint European observatory be established in the southern hemisphere. At the time, all reflector telescopes with an aperture of 2 metres or more were located in the northern hemisphere. The decision to build the observatory in the southern hemisphere resulted from the necessity of observing the southern sky, although it was initially planned to set up telescopes in South Africa, tests from 1955 to 1963 demonstrated that a site in the Andes was preferable. On November 15,1963 Chile was chosen as the site for ESOs observatory, the decision was preceded by the ESO Convention, signed 5 October 1962 by Belgium, Germany, France, the Netherlands and Sweden. Otto Heckmann was nominated as the organisations first director general on 1 November 1962, a preliminary proposal for a convention of astronomy organisations in these five countries was drafted in 1954. Although some amendments were made in the document, the convention proceeded slowly until 1960 when it was discussed during that years committee meeting. The new draft was examined in detail, and a member of CERN highlighted the need for a convention between governments. The convention and government involvement became pressing due to rising costs of site-testing expeditions. The final 1962 version was adopted from the CERN convention
. Bibcode:2005MNRAS.359..223F. doi:10.1111/j.1365-2966.2005.08891.x.
