Arizona is a state in the southwestern region of the United States. It is part of the Western and the Mountain states, it is the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona shares the Four Corners region with Utah and New Mexico. Arizona is the 48th state and last of the contiguous states to be admitted to the Union, achieving statehood on February 14, 1912, coinciding with Valentine's Day. Part of the territory of Alta California in New Spain, it became part of independent Mexico in 1821. After being defeated in the Mexican–American War, Mexico ceded much of this territory to the United States in 1848; the southernmost portion of the state was acquired in 1853 through the Gadsden Purchase. Southern Arizona is known for its desert climate, with hot summers and mild winters. Northern Arizona features forests of pine, Douglas fir, spruce trees. There are ski resorts in the areas of Flagstaff and Tucson. In addition to the Grand Canyon National Park, there are several national forests, national parks, national monuments.
About one-quarter of the state is made up of Indian reservations that serve as the home of 27 federally recognized Native American tribes, including the Navajo Nation, the largest in the state and the United States, with more than 300,000 citizens. Although federal law gave all Native Americans the right to vote in 1924, Arizona excluded those living on reservations in the state from voting until the state Supreme Court ruled in favor of Native American plaintiffs in Trujillo v. Garley; the state's name appears to originate from an earlier Spanish name, derived from the O'odham name alĭ ṣonak, meaning "small spring", which applied only to an area near the silver mining camp of Planchas de Plata, Sonora. To the European settlers, their pronunciation sounded like "Arissona"; the area is still known as alĭ ṣonak in the O'odham language. Another possible origin is the Basque phrase haritz ona, as there were numerous Basque sheepherders in the area. A native Mexican of Basque heritage established the ranchería of Arizona between 1734 and 1736 in the current Mexican state of Sonora, which became notable after a significant discovery of silver there, c.
1737. There is a misconception. For thousands of years before the modern era, Arizona was home to numerous Native American tribes. Hohokam and Ancestral Puebloan cultures were among the many that flourished throughout the state. Many of their pueblos, cliffside dwellings, rock paintings and other prehistoric treasures have survived, attracting thousands of tourists each year; the first European contact by native peoples was with Marcos de Niza, a Spanish Franciscan, in 1539. He explored parts of the present state and made contact with native inhabitants the Sobaipuri; the expedition of Spanish explorer Coronado entered the area in 1540–1542 during its search for Cíbola. Few Spanish settlers migrated to Arizona. One of the first settlers in Arizona was José Romo de Vivar. Father Kino was the next European in the region. A member of the Society of Jesus, he led the development of a chain of missions in the region, he converted many of the Indians to Christianity in the Pimería Alta in the 1690s and early 18th century.
Spain founded presidios at Tubac in 1752 and Tucson in 1775. When Mexico achieved its independence from the Kingdom of Spain and its Spanish Empire in 1821, what is now Arizona became part of its Territory of Nueva California known as Alta California. Descendants of ethnic Spanish and mestizo settlers from the colonial years still lived in the area at the time of the arrival of European-American migrants from the United States. During the Mexican–American War, the U. S. Army occupied the national capital of Mexico City and pursued its claim to much of northern Mexico, including what became Arizona Territory in 1863 and the State of Arizona in 1912; the Treaty of Guadalupe Hidalgo specified that, in addition to language and cultural rights of the existing inhabitants of former Mexican citizens being considered as inviolable, the sum of US$15 million dollars in compensation be paid to the Republic of Mexico. In 1853, the U. S. acquired the land south below the Gila River from Mexico in the Gadsden Purchase along the southern border area as encompassing the best future southern route for a transcontinental railway.
What is now known as the state of Arizona was administered by the United States government as part of the Territory of New Mexico until the southern part of that region seceded from the Union to form the Territory of Arizona. This newly established territory was formally organized by the Confederate States government on Saturday, January 18, 1862, when President Jefferson Davis approved and signed An Act to Organize the Territory of Arizona, marking the first official use of the name "Territory of Arizona"; the Southern territory supplied the Confederate government with men and equipment. Formed in 1862, Arizona scout companies served with the Confederate States Army duri
Titan is the largest moon of Saturn and the second-largest natural satellite in the Solar System. It is the only moon known to have a dense atmosphere, the only object in space, other than Earth, where clear evidence of stable bodies of surface liquid has been found. Titan is the sixth gravitationally rounded moon from Saturn. Described as a planet-like moon, Titan is 50% larger than Earth's moon and 80% more massive, it is the second-largest moon in the Solar System after Jupiter's moon Ganymede, is larger than the planet Mercury, but only 40% as massive. Discovered in 1655 by the Dutch astronomer Christiaan Huygens, Titan was the first known moon of Saturn, the sixth known planetary satellite. Titan orbits Saturn at 20 Saturn radii. From Titan's surface, Saturn subtends an arc of 5.09 degrees and would appear 11.4 times larger in the sky than the Moon from Earth. Titan is composed of ice and rocky material. Much as with Venus before the Space Age, the dense opaque atmosphere prevented understanding of Titan's surface until the Cassini–Huygens mission in 2004 provided new information, including the discovery of liquid hydrocarbon lakes in Titan's polar regions.
The geologically young surface is smooth, with few impact craters, although mountains and several possible cryovolcanoes have been found. The atmosphere of Titan is nitrogen; the climate—including wind and rain—creates surface features similar to those of Earth, such as dunes, lakes and deltas, is dominated by seasonal weather patterns as on Earth. With its liquids and robust nitrogen atmosphere, Titan's methane cycle is analogous to Earth's water cycle, at the much lower temperature of about 94 K. Titan was discovered on March 25, 1655, by the Dutch astronomer Christiaan Huygens. Huygens was inspired by Galileo's discovery of Jupiter's four largest moons in 1610 and his improvements in telescope technology. Christiaan, with the help of his older brother Constantijn Huygens, Jr. began building telescopes around 1650 and discovered the first observed moon orbiting Saturn with one of the telescopes they built. It was the sixth moon discovered, after Earth's Moon and the Galilean moons of Jupiter.
Huygens named his discovery Saturni Luna, publishing in the 1655 tract De Saturni Luna Observatio Nova. After Giovanni Domenico Cassini published his discoveries of four more moons of Saturn between 1673 and 1686, astronomers fell into the habit of referring to these and Titan as Saturn I through V. Other early epithets for Titan include "Saturn's ordinary satellite". Titan is numbered Saturn VI because after the 1789 discoveries the numbering scheme was frozen to avoid causing any more confusion. Numerous small moons have been discovered closer to Saturn since then; the name Titan, the names of all seven satellites of Saturn known, came from John Herschel, in his 1847 publication Results of Astronomical Observations Made during the Years 1834, 5, 6, 7, 8, at the Cape of Good Hope. He suggested the names of the mythological Titans and sisters of Cronus, the Greek Saturn. In Greek mythology, the Titans were a race of powerful deities, descendants of Gaia and Uranus, that ruled during the legendary Golden Age.
Titan orbits Saturn once 22 hours. Like the Moon and many of the satellites of the giant planets, its rotational period is identical to its orbital period; because of this, there is a sub-Saturnian point on its surface, from which the planet would always appear to hang directly overhead. Longitudes on Titan are measured westward, starting from the meridian passing through this point, its orbital eccentricity is 0.0288, the orbital plane is inclined 0.348 degrees relative to the Saturnian equator. Viewed from Earth, Titan reaches an angular distance of about 20 Saturn radii from Saturn and subtends a disk 0.8 arcseconds in diameter. The small, irregularly shaped satellite Hyperion is locked in a 3:4 orbital resonance with Titan. A "slow and smooth" evolution of the resonance—in which Hyperion migrated from a chaotic orbit—is considered unlikely, based on models. Hyperion formed in a stable orbital island, whereas the massive Titan absorbed or ejected bodies that made close approaches. Titan is 5,149.46 kilometers in diameter, 1.06 times that of the planet Mercury, 1.48 that of the Moon, 0.40 that of Earth.
Before the arrival of Voyager 1 in 1980, Titan was thought to be larger than Ganymede and thus the largest moon in the Solar System. Titan's diameter and mass are similar to those of the Jovian moons Callisto. Based on its bulk density of 1.88 g/cm3, Titan's composition is half water ice and half rocky material. Though similar in composition to Dione and Enceladus, it is denser due to gravitational compression, it has a mass 1/4226 that of Saturn, making it the largest moon of the gas giants relative to the ma
California is a state in the Pacific Region of the United States. With 39.6 million residents, California is the most populous U. S. the third-largest by area. The state capital is Sacramento; the Greater Los Angeles Area and the San Francisco Bay Area are the nation's second and fifth most populous urban regions, with 18.7 million and 9.7 million residents respectively. Los Angeles is California's most populous city, the country's second most populous, after New York City. California has the nation's most populous county, Los Angeles County, its largest county by area, San Bernardino County; the City and County of San Francisco is both the country's second-most densely populated major city after New York City and the fifth-most densely populated county, behind only four of the five New York City boroughs. California's $3.0 trillion economy is larger than that of any other state, larger than those of Texas and Florida combined, the largest sub-national economy in the world. If it were a country, California would be the 5th largest economy in the world, the 36th most populous as of 2017.
The Greater Los Angeles Area and the San Francisco Bay Area are the nation's second- and third-largest urban economies, after the New York metropolitan area. The San Francisco Bay Area PSA had the nation's highest GDP per capita in 2017 among large PSAs, is home to three of the world's ten largest companies by market capitalization and four of the world's ten richest people. California is considered a global trendsetter in popular culture, innovation and politics, it is considered the origin of the American film industry, the hippie counterculture, fast food, the Internet, the personal computer, among others. The San Francisco Bay Area and the Greater Los Angeles Area are seen as global centers of the technology and entertainment industries, respectively. California has a diverse economy: 58% of the state's economy is centered on finance, real estate services and professional, scientific and technical business services. Although it accounts for only 1.5% of the state's economy, California's agriculture industry has the highest output of any U.
S. state. California is bordered by Oregon to the north and Arizona to the east, the Mexican state of Baja California to the south; the state's diverse geography ranges from the Pacific Coast in the west to the Sierra Nevada mountain range in the east, from the redwood–Douglas fir forests in the northwest to the Mojave Desert in the southeast. The Central Valley, a major agricultural area, dominates the state's center. Although California is well-known for its warm Mediterranean climate, the large size of the state results in climates that vary from moist temperate rainforest in the north to arid desert in the interior, as well as snowy alpine in the mountains. Over time and wildfires have become more pervasive features. What is now California was first settled by various Native Californian tribes before being explored by a number of European expeditions during the 16th and 17th centuries; the Spanish Empire claimed it as part of Alta California in their New Spain colony. The area became a part of Mexico in 1821 following its successful war for independence but was ceded to the United States in 1848 after the Mexican–American War.
The western portion of Alta California was organized and admitted as the 31st state on September 9, 1850. The California Gold Rush starting in 1848 led to dramatic social and demographic changes, with large-scale emigration from the east and abroad with an accompanying economic boom; the word California referred to the Baja California Peninsula of Mexico. The name derived from the mythical island California in the fictional story of Queen Calafia, as recorded in a 1510 work The Adventures of Esplandián by Garci Rodríguez de Montalvo; this work was the fifth in a popular Spanish chivalric romance series that began with Amadis de Gaula. Queen Calafia's kingdom was said to be a remote land rich in gold and pearls, inhabited by beautiful black women who wore gold armor and lived like Amazons, as well as griffins and other strange beasts. In the fictional paradise, the ruler Queen Calafia fought alongside Muslims and her name may have been chosen to echo the title of a Muslim leader, the Caliph. It's possible.
Know ye that at the right hand of the Indies there is an island called California close to that part of the Terrestrial Paradise, inhabited by black women without a single man among them, they lived in the manner of Amazons. They were robust of body with great virtue; the island itself is one of the wildest in the world on account of the craggy rocks. Shortened forms of the state's name include CA, Cal. Calif. and US-CA. Settled by successive waves of arrivals during the last 10,000 years, California was one of the most culturally and linguistically diverse areas in pre-Columbian North America. Various estimates of the native population range from 100,000 to 300,000; the Indigenous peoples of California included more than 70 distinct groups of Native Americans, ranging from large, settled populations living on the coast to groups in the interior. California groups were diverse in their political organization with bands, villages, on the resource-rich coasts, large chiefdoms, such as the Chumash and Salinan.
Trade, intermarriage a
Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System after Mercury. In English, Mars carries a name of the Roman god of war, is referred to as the "Red Planet" because the reddish iron oxide prevalent on its surface gives it a reddish appearance, distinctive among the astronomical bodies visible to the naked eye. Mars is a terrestrial planet with a thin atmosphere, having surface features reminiscent both of the impact craters of the Moon and the valleys and polar ice caps of Earth; the days and seasons are comparable to those of Earth, because the rotational period as well as the tilt of the rotational axis relative to the ecliptic plane are similar. Mars is the site of Olympus Mons, the largest volcano and second-highest known mountain in the Solar System, of Valles Marineris, one of the largest canyons in the Solar System; the smooth Borealis basin in the northern hemisphere covers 40% of the planet and may be a giant impact feature. Mars has two moons and Deimos, which are small and irregularly shaped.
These may be captured asteroids, similar to a Mars trojan. There are ongoing investigations assessing the past habitability potential of Mars, as well as the possibility of extant life. Future astrobiology missions are planned, including the Mars 2020 and ExoMars rovers. Liquid water cannot exist on the surface of Mars due to low atmospheric pressure, less than 1% of the Earth's, except at the lowest elevations for short periods; the two polar ice caps appear to be made of water. The volume of water ice in the south polar ice cap, if melted, would be sufficient to cover the entire planetary surface to a depth of 11 meters. In November 2016, NASA reported finding a large amount of underground ice in the Utopia Planitia region of Mars; the volume of water detected has been estimated to be equivalent to the volume of water in Lake Superior. Mars can be seen from Earth with the naked eye, as can its reddish coloring, its apparent magnitude reaches −2.94, surpassed only by Jupiter, the Moon, the Sun.
Optical ground-based telescopes are limited to resolving features about 300 kilometers across when Earth and Mars are closest because of Earth's atmosphere. Mars is half the diameter of Earth with a surface area only less than the total area of Earth's dry land. Mars is less dense than Earth, having about 15% of Earth's volume and 11% of Earth's mass, resulting in about 38% of Earth's surface gravity; the red-orange appearance of the Martian surface is caused by rust. It can look like butterscotch. Like Earth, Mars has differentiated into a dense metallic core overlaid by less dense materials. Current models of its interior imply a core with a radius of about 1,794 ± 65 kilometers, consisting of iron and nickel with about 16–17% sulfur; this iron sulfide core is thought to be twice as rich in lighter elements as Earth's. The core is surrounded by a silicate mantle that formed many of the tectonic and volcanic features on the planet, but it appears to be dormant. Besides silicon and oxygen, the most abundant elements in the Martian crust are iron, aluminum and potassium.
The average thickness of the planet's crust is about 50 km, with a maximum thickness of 125 km. Earth's crust averages 40 km. Mars is a terrestrial planet that consists of minerals containing silicon and oxygen and other elements that make up rock; the surface of Mars is composed of tholeiitic basalt, although parts are more silica-rich than typical basalt and may be similar to andesitic rocks on Earth or silica glass. Regions of low albedo suggest concentrations of plagioclase feldspar, with northern low albedo regions displaying higher than normal concentrations of sheet silicates and high-silicon glass. Parts of the southern highlands include detectable amounts of high-calcium pyroxenes. Localized concentrations of hematite and olivine have been found. Much of the surface is covered by finely grained iron oxide dust. Although Mars has no evidence of a structured global magnetic field, observations show that parts of the planet's crust have been magnetized, suggesting that alternating polarity reversals of its dipole field have occurred in the past.
This paleomagnetism of magnetically susceptible minerals is similar to the alternating bands found on Earth's ocean floors. One theory, published in 1999 and re-examined in October 2005, is that these bands suggest plate tectonic activity on Mars four billion years ago, before the planetary dynamo ceased to function and the planet's magnetic field faded, it is thought that, during the Solar System's formation, Mars was created as the result of a stochastic process of run-away accretion of material from the protoplanetary disk that orbited the Sun. Mars has many distinctive chemical features caused by its position in the Solar System. Elements with comparatively low boiling points, such as chlorine and sulphur, are much more common on Mars than Earth. After the formation of the planets, all were subjected to the so-called "Late Heavy Bombardment". About 60% of the surface of Mars shows a record of impacts from that era, whereas much of the remaining surface is underlain by immense impact basins caused by those events.
There is evidence of an enormous impact basin in the northern hemisphere of Mars, spanning 10,600 by 8,500 km, or four times the size of the Moon's South Pole – Aitk
The Solar System is the gravitationally bound planetary system of the Sun and the objects that orbit it, either directly or indirectly. Of the objects that orbit the Sun directly, the largest are the eight planets, with the remainder being smaller objects, such as the five dwarf planets and small Solar System bodies. Of the objects that orbit the Sun indirectly—the moons—two are larger than the smallest planet, Mercury; the Solar System formed 4.6 billion years ago from the gravitational collapse of a giant interstellar molecular cloud. The vast majority of the system's mass is in the Sun, with the majority of the remaining mass contained in Jupiter; the four smaller inner planets, Venus and Mars, are terrestrial planets, being composed of rock and metal. The four outer planets are giant planets, being more massive than the terrestrials; the two largest and Saturn, are gas giants, being composed of hydrogen and helium. All eight planets have circular orbits that lie within a nearly flat disc called the ecliptic.
The Solar System contains smaller objects. The asteroid belt, which lies between the orbits of Mars and Jupiter contains objects composed, like the terrestrial planets, of rock and metal. Beyond Neptune's orbit lie the Kuiper belt and scattered disc, which are populations of trans-Neptunian objects composed of ices, beyond them a newly discovered population of sednoids. Within these populations are several dozen to tens of thousands of objects large enough that they have been rounded by their own gravity; such objects are categorized as dwarf planets. Identified dwarf planets include the trans-Neptunian objects Pluto and Eris. In addition to these two regions, various other small-body populations, including comets and interplanetary dust clouds travel between regions. Six of the planets, at least four of the dwarf planets, many of the smaller bodies are orbited by natural satellites termed "moons" after the Moon; each of the outer planets is encircled by planetary rings of dust and other small objects.
The solar wind, a stream of charged particles flowing outwards from the Sun, creates a bubble-like region in the interstellar medium known as the heliosphere. The heliopause is the point at which pressure from the solar wind is equal to the opposing pressure of the interstellar medium; the Oort cloud, thought to be the source for long-period comets, may exist at a distance a thousand times further than the heliosphere. The Solar System is located in the Orion Arm, 26,000 light-years from the center of the Milky Way galaxy. For most of history, humanity did not understand the concept of the Solar System. Most people up to the Late Middle Ages–Renaissance believed Earth to be stationary at the centre of the universe and categorically different from the divine or ethereal objects that moved through the sky. Although the Greek philosopher Aristarchus of Samos had speculated on a heliocentric reordering of the cosmos, Nicolaus Copernicus was the first to develop a mathematically predictive heliocentric system.
In the 17th century, Galileo discovered that the Sun was marked with sunspots, that Jupiter had four satellites in orbit around it. Christiaan Huygens followed on from Galileo's discoveries by discovering Saturn's moon Titan and the shape of the rings of Saturn. Edmond Halley realised in 1705 that repeated sightings of a comet were recording the same object, returning once every 75–76 years; this was the first evidence that anything other than the planets orbited the Sun. Around this time, the term "Solar System" first appeared in English. In 1838, Friedrich Bessel measured a stellar parallax, an apparent shift in the position of a star created by Earth's motion around the Sun, providing the first direct, experimental proof of heliocentrism. Improvements in observational astronomy and the use of unmanned spacecraft have since enabled the detailed investigation of other bodies orbiting the Sun; the principal component of the Solar System is the Sun, a G2 main-sequence star that contains 99.86% of the system's known mass and dominates it gravitationally.
The Sun's four largest orbiting bodies, the giant planets, account for 99% of the remaining mass, with Jupiter and Saturn together comprising more than 90%. The remaining objects of the Solar System together comprise less than 0.002% of the Solar System's total mass. Most large objects in orbit around the Sun lie near the plane of Earth's orbit, known as the ecliptic; the planets are close to the ecliptic, whereas comets and Kuiper belt objects are at greater angles to it. All the planets, most other objects, orbit the Sun in the same direction that the Sun is rotating. There are exceptions, such as Halley's Comet; the overall structure of the charted regions of the Solar System consists of the Sun, four small inner planets surrounded by a belt of rocky asteroids, four giant planets surrounded by the Kuiper belt of icy objects. Astronomers sometimes informally divide this structure into separate regions; the inner Solar System includes the asteroid belt. The outer Solar System is including the four giant planets.
Since the discovery of the Kuiper belt, the outermost parts of the Solar Sys
Yerkes Observatory is an astronomical observatory in Williams Bay, Wisconsin operated by the University of Chicago Department of Astronomy and Astrophysics. It closed public operations in 2018; the observatory, which called itself "the birthplace of modern astrophysics", was founded in 1897 by astronomer George Ellery Hale and financed by businessman Charles T. Yerkes, it represented a shift in the thinking about observatories, from their being mere housing for telescopes and observers, to the early-20th-century concept of observation equipment integrated with laboratory space for physics and chemistry. The observatory houses a 40-inch diameter doublet lens refracting telescope, the largest successfully used for astronomy, a collection of over 170,000 photographic plates. Notable astronomers who conducted research at Yerkes include Edwin Hubble, Subrahmanyan Chandrasekhar, Russian-American astronomer Otto Struve, Dutch-American astronomer Gerard Kuiper, the twentieth-century popularizer of astronomy Carl Sagan.
Yerkes Observatory's 40 in refracting telescope has a lens produced by the optical firm Alvan Clark & Sons and a mounting by the Warner & Swasey Company. It is the largest refracting telescope used for astronomical research; the mounting and tube for the 40-inch telescope was exhibited at the 1893 World's Columbian Exposition in Chicago before being installed in the observatory. The grinding of the lens was completed later; the observatory houses 40 in and 24 in reflecting telescopes. Several smaller telescopes are used for educational purposes. Both telescopes are available on Skynet Junior Scholars, the 40-inch reflector helped pioneer the field of adaptive optics. Research conducted at Yerkes in the last decade includes work on the interstellar medium, globular cluster formation, infrared astronomy, near-Earth objects; until the University of Chicago maintained an engineering center in the observatory, dedicated to building and maintaining scientific instruments. In 2012 the engineers completed work on the High-resolution Airborne Wideband Camera, part of the Stratospheric Observatory for Infrared Astronomy.
Researchers use the Yerkes collection of over 170,000 archival photographic plates that date back to the 1890s. The past few years have seen astronomical research replaced by educational outreach and astronomical tourism activities. In March 2005, the University of Chicago announced plans to sell the observatory and its land on the shore of Geneva Lake. Two purchasers had expressed an interest: Mirbeau, an East Coast developer that wanted to build luxury homes, Aurora University, which has a campus straddling the Williams Bay property; the Geneva Lake Conservancy, a regional conservation and land trust organization, maintained that it was critical to save the historic Yerkes Observatory structures and telescopes for education and research, as well as to conserve the rare undeveloped, wooded lakefront and deep forest sections of the 77-acre site. On June 7, 2006, the University announced it would sell the facility to Mirbeau for US$8 million with stipulations to preserve the observatory, the surrounding 30 acres, the entire shoreline of the site.
Under the Mirbeau plan, a 100-room resort with a large spa operation and attendant parking and support facilities was to be located on the 9-acre virgin wooded Yerkes land on the lakeshore—the last such undeveloped, natural site on Geneva Lake's 21-mile shoreline. About 70 homes were to be developed on the upper Yerkes property surrounding the historic observatory; these grounds had been designed more than 100 years by John Charles Olmsted, the nephew and adopted son of famed landscape architect Frederick Law Olmsted. Williams Bay's refusal to change the zoning from education to residential caused Mirbeau to abandon its development plans. In view of the public controversy surrounding the development proposals, the university suspended these plans in January 2007; the university's department of astronomy and astrophysics formed a study group, including representatives from the faculty and observatory and a wide range of other involved parties, to plan for the operation of a regional center for science education at the observatory.
The study group began its work in February 2007 and issued its final report November 30, 2007. The report recommended creating a formal business plan to ensure the financial viability of the proposed science education center, establishing ownership of the proposed center before initiating plans for creating it, forming a partnership between the University of Chicago and local interests to plan for the center, it suggested that some lakefront and woods parcels could be sold for residential development. In March 2018, the University of Chicago announced that it would no longer operate the observatory after October 1, 2018, would be seeking a new owner. In May 2018, the Yerkes Future Foundation, a group of concerned local residents, submitted an expression of interest to the University of Chicago with a proposal that would seek to maintain public access to the site and continuation of the educational programs. No successor operator had been identified by the end of August, plans were put in place to close the facility on October 1.
As of September 14, 2018 the University's talks continue with the Yerkes Future Foundation, but no long term plans have been announced by the University of Chicago for Yerkes Observatory aft
The Apollo program known as Project Apollo, was the third United States human spaceflight program carried out by the National Aeronautics and Space Administration, which succeeded in landing the first humans on the Moon from 1969 to 1972. First conceived during Dwight D. Eisenhower's administration as a three-man spacecraft to follow the one-man Project Mercury which put the first Americans in space, Apollo was dedicated to President John F. Kennedy's national goal of "landing a man on the Moon and returning him safely to the Earth" by the end of the 1960s, which he proposed in an address to Congress on May 25, 1961, it was the third US human spaceflight program to fly, preceded by the two-man Project Gemini conceived in 1961 to extend spaceflight capability in support of Apollo. Kennedy's goal was accomplished on the Apollo 11 mission when astronauts Neil Armstrong and Buzz Aldrin landed their Apollo Lunar Module on July 20, 1969, walked on the lunar surface, while Michael Collins remained in lunar orbit in the command and service module, all three landed safely on Earth on July 24.
Five subsequent Apollo missions landed astronauts on the Moon, the last in December 1972. In these six spaceflights, twelve men walked on the Moon. Apollo ran from 1961 to 1972, with the first manned flight in 1968, it achieved its goal of manned lunar landing, despite the major setback of a 1967 Apollo 1 cabin fire that killed the entire crew during a prelaunch test. After the first landing, sufficient flight hardware remained for nine follow-on landings with a plan for extended lunar geological and astrophysical exploration. Budget cuts forced the cancellation of three of these. Five of the remaining six missions achieved successful landings, but the Apollo 13 landing was prevented by an oxygen tank explosion in transit to the Moon, which destroyed the service module's capability to provide electrical power, crippling the CSM's propulsion and life support systems; the crew returned to Earth safely by using the lunar module as a "lifeboat" for these functions. Apollo used Saturn family rockets as launch vehicles, which were used for an Apollo Applications Program, which consisted of Skylab, a space station that supported three manned missions in 1973–74, the Apollo–Soyuz Test Project, a joint US-Soviet Union Earth-orbit mission in 1975.
Apollo set several major human spaceflight milestones. It stands alone in sending manned missions beyond low Earth orbit. Apollo 8 was the first manned spacecraft to orbit another celestial body, while the final Apollo 17 mission marked the sixth Moon landing and the ninth manned mission beyond low Earth orbit; the program returned 842 pounds of lunar rocks and soil to Earth contributing to the understanding of the Moon's composition and geological history. The program laid the foundation for NASA's subsequent human spaceflight capability and funded construction of its Johnson Space Center and Kennedy Space Center. Apollo spurred advances in many areas of technology incidental to rocketry and manned spaceflight, including avionics, telecommunications, computers; the Apollo program was conceived during the Eisenhower administration in early 1960, as a follow-up to Project Mercury. While the Mercury capsule could only support one astronaut on a limited Earth orbital mission, Apollo would carry three astronauts.
Possible missions included ferrying crews to a space station, circumlunar flights, eventual manned lunar landings. The program was named after Apollo, the Greek god of light and the sun, by NASA manager Abe Silverstein, who said that "I was naming the spacecraft like I'd name my baby." Silverstein chose the name at home one evening, early in 1960, because he felt "Apollo riding his chariot across the Sun was appropriate to the grand scale of the proposed program."In July 1960, NASA Deputy Administrator Hugh L. Dryden announced the Apollo program to industry representatives at a series of Space Task Group conferences. Preliminary specifications were laid out for a spacecraft with a mission module cabin separate from the command module, a propulsion and equipment module. On August 30, a feasibility study competition was announced, on October 25, three study contracts were awarded to General Dynamics/Convair, General Electric, the Glenn L. Martin Company. Meanwhile, NASA performed its own in-house spacecraft design studies led by Maxime Faget, to serve as a gauge to judge and monitor the three industry designs.
In November 1960, John F. Kennedy was elected president after a campaign that promised American superiority over the Soviet Union in the fields of space exploration and missile defense. Up to the election of 1960, Kennedy had been speaking out against the "missile gap" that he and many other senators felt had developed between the Soviet Union and United States due to the inaction of President Eisenhower. Beyond military power, Kennedy used aerospace technology as a symbol of national prestige, pledging to make the US not "first but, first and, first if, but first period." Despite Kennedy's rhetoric, he did not come to a decision on the status of the Apollo program once he became president. He knew little about the technical details of the space program, was put off by the massive financial commitment required by a manned Moon landing; when Kennedy's newly appointed NASA Administrator James E. Webb requested a 30 percent budget increase for his agency, Kennedy supported an acceleration of NASA's large booster program but deferred a decision on the broader issue.
On April 12, 1961, Soviet cosmonaut Yuri Gagarin became the first person to fly in space, reinforcing American fears about being left behind in a technological competition with the Soviet Union. At a meeting of the US House Committee on Science and Astronaut