Karen Hill

The USSR’s Martian program did not meet expectations, whereas its 1985 Vega probes to Venus and Halley’s comet were unmitigated successes. By 1985, international relations had eased to the point where the USSR, the United States, Europe, Brazil, and Australia all shared information on this venture. Vega 1 and Vega 2 were launched in December … Read more

Since telescopes were first used by Galileo in the early seventeenth century, astronomers have dreamed of placing them where Earth’s atmosphere would not get in the way of viewing the universe. The Hubble Space Telescope (HST) fulfills that dream. The Hubble Space Telescope, a reflecting telescope, is not the largest telescope made on Earth. Its … Read more

An international fleet of probes were launched to intercept the orbit of Halley’s comet in 1986. The Soviet Vega 1 probe was the first to reach its destination, on March 6, coming within 5,000 miles (8,000 km) of the comet’s nucleus. Vega 2 arrived to take photos from a distance of 13,000 miles (21,000 km) … Read more

NASA spent some 30 years thinking about, designing, creating, and testing a telescope that would be launched into orbit. The result, the Hubble Space Telescope, was ready for launch in 1985. Its mission would be to observe the solar system and the galaxies beyond it without the interference of Earth’s atmosphere. Early in 1986, however, … Read more

Fortunately, NASA made plans for repairing the Hubble Space Telescope throughout its projected 15-year orbit. Two months after the Hubble Space Telescope’s launch in 1990, it was discovered that the primary mirror had not been ground properly, among other problems. The telescope could not be focused. While this was a major embarrassment, the dangerous and … Read more

The idea of colonies of humans on the Moon or Mars lies not only between the pages of science fiction paperbacks. NASA has been planning a lunar base since the 1960s. Investment in the space shuttle program drew attention away from this goal, but interest has been revived. In 1991, veteran astronauts described some likely … Read more

Plans change all the time, due to budgetary and governmental constraints, but the next planned space spectacular is an extended trip around Saturn and a landing on its moon Titan. The mission is a collaborative effort between the ESA and NASA. The spacecraft Cassini, as it is called, has been partly developed from Mariner, Viking, … Read more

Voyager 2 was launched first, on August 20, 1977, but Voyager 1, launched on September 5, 1977, beat it to Jupiter. Voyager 1 made its closest pass on March 5, 1979, and collected detailed information about the planet and its moons. Voyager 2 got to Jupiter in July 1979. In November 1980, Voyager 1 transmitted … Read more

Mariner probes had already orbited Mars, but NASA’s Viking program was designed specifically to land on the planet in search of, among other things, life. Viking 1 went into orbit around Mars on June 19, 1976. NASA planned to send a module to land on the surface on Independence Day, to celebrate the U.S. bicentennial, … Read more

Launched on November 6, 1996, NASA’s Mars Global Surveyor probe was designed primarily to study past and present climate patterns, carry out studies of geology and natural resources to determine the possibility of Mars supporting manned missions; and, of course, to look for life. Many astronomers believe that signs of life on the planet point … Read more

The Soviet Venera program focused on landing a probe on Venus, and ten Venera probes successfully landed on the planet. The first probes sent back data and images from within the planet’s atmosphere before being burned up by the incredible temperatures or crushed by the monumental atmospheric pressure. Venera 7 touched down on July 22, … Read more

The USSR’s Mars program, which had probes named after the planet, had more than its fair share of misfortune, including failed launches, unsuccessful attempts to leave Earth’s orbit, completely missing Mars, and even death. Scientists set out to investigate the failed launch of an early probe; it exploded, killing most of the team. Out of … Read more

The Soviet Phobos program from 1988-1989 was intended to erase the bad memories of the largely disastrous Mars program of the 1970s. Designed to orbit Mars and land on the planet’s moon Phobos, two Phobos probes were launched in July 1988. An incorrect command sent to Phobos I shut the probe down and it was … Read more

NASA developed a number of Orbital Solar Observatories (OSO), which were launched between 1962 and 1975. Their purpose was to observe the Sun’s ultraviolet, gamma, and X rays throughout an 11-year sunspot cycle. From 1973 to 1974, a special Apollo Telescope Mount (ATM) was attached to Skylab for observation of the Sun. The successor to … Read more

Once the race to the Moon was over, attention could be refocused on long-range missions. The idea of a permanently manned, international space station came into favor. Funding was short and NASA’s first priority became the space shuttle, but in 1984, President Reagan announced in his inaugural speech that such a station would be next … Read more

Space probes are unmanned spacecraft fitted with instruments to gather and transmit data and images from space. Because the probes are self-sufficient, they can be sent where no person could survive: into orbit around the Sun, to the other planets, or even out beyond the solar system. The downside of unmanned probes is that malfunctions … Read more

Advances in understanding and technology, as well as the failure of some probes to perform their tasks, make it important to send probes time and again to the same planet. We don’t know what we will find when we receive information from a distant probe. Every probe sent to Jupiter, for example, raises more questions … Read more

Mariner 2, the first successful planetary probe launch, was sent into Earth’s orbit on August 27, 1962. From there a rocket fired it on a 4-month journey to Venus. On November 28, 1965, Mariner 4 came within 540 miles (870 km) of Mars and sent back the first pictures of the planet’s surface. Mariner 6 … Read more

Pioneer 10 (1972-1973) was designed to send radio signals back to Earth from Jupiter. It took the probe 21 months to reach the gas giant. While it had no cameras, it was also able to scan part of Jupiter’s surface and send back clearer images than had ever been taken from Earth. Pioneer 11 (1973-1974) … Read more

Most industrialized countries probably have some kind of space program. This is not to say that they all put people into space. Most concentrate on launching communications and/or surveillance satellites. Manned space flight is becoming more and more a cooperative international effort. For example, the Freedom space station, announced in President Ronald Reagan’s 1984 State … Read more

The USSR developed and built the space shuttle Buran in the late 1970s and 1980s. Buran looks very much like the U.S. space shuttle. The USSR space shuttle took off on its maiden voyage in November 1988. Unlike the U.S. space shuttle, which takes off under its own power, Buran was rocketed into orbit and … Read more

A joint space mission between NASA and the European Space Agency (ESA), Spacelab was first launched in November 1983. Spacelab is not a spacecraft in and of itself. It consists of varying modules that travel attached to the space shuttle for the purposes of conducting specific research. Spacelab allowed scientists to perform experiments in microgravity … Read more

Cosmonauts wear space suits now, at least during takeoff, landing, and docking. Originally, space suits were not required, and some cosmonauts flew in their underwear. But on June 29, 1971, when the three cosmonauts in Soyuz 11 undocked from the space station Salyut 1, an air release valve suddenly opened. Without the life-support systems of … Read more

Space suits on the space shuttles are required only for launch and landing. There are so many astronauts now, space suits are no longer individually tailored to each one. The different parts, arms, legs, torso, etc., come in different sizes and need only be attached to each other for a customized fit. A layer of … Read more

What Is the Function of a Space Station and What Is the Difference Between a Space Station and a Spacecraft? A space station is an orbiting satellite that is meant to accommodate a crew of astronauts over an extended period of time, weeks or even months. Space stations are used to study the effects of … Read more

On April 19, 1971, the USSR launched the first manned space station, Salyut 1, into orbit around Earth. The station consisted of four compartments, and was meant to house three crew members for up to 4 weeks. The entry compartment had the docking equipment for the spacecraft that would carry cosmonauts to and from the … Read more

The first U.S. version of a space station, Skylab, was launched on May 14, 1973. The astronauts on the first mission had to spend a great deal of time repairing the station, which had seriously malfunctioned from the time it took off. They were able to fix it and complete their planned experiments within 28 … Read more

Originally, the space shuttle was meant to be a transport system to and from a space station. Due to financial cutbacks and shifts in priority at NASA, the space station never materialized back then, but the space shuttle did. The space shuttle became an orbiting laboratory as well a reusable spacecraft for transportation into space. … Read more

The USSR launched five missions (Zond 4-8) between 1968 and 1970, apparently as tests for a manned Moon landing, but the exact purpose of the missions has never been fully revealed to the scientific community. The Soviet lunar program was dropped 3 years after U.S. astronauts Armstrong and Aldrin made it to the Moon and … Read more

Traveling in space is dangerous. No possibility of life exists beyond the support functions brought from Earth. Getting off and back onto Earth requires the use of highly volatile and dangerous materials. Space travelers are face-to-face not only with the laws of physics, but also their own mortality. The first fatal accident occurred on January … Read more

Space suits are required by astronauts because body fluids would boil under the natural pressure in space. Even pilots of high-flying aircraft need pressurized suits, and NASA developed space suits for the Mercury astronauts from those originally worn by U.S. Navy jet pilots. Space suits have come a long way since Soviet cosmonauts flew in … Read more

In 1972, the United States and USSR agreed to meet in space. Three years later, Soyuz 19 and an Apollo capsule, the last to be used in the space program, docked and for 2 days exchanged crews and good will. In preparation for this historic, albeit mostly symbolic, mission, many problems had to be overcome. … Read more

When astronauts began walking in space, their suits had to be further altered to give more mobility and comfort while providing more protection from micrometeorites and accidental rips and tears. The Gemini space suits were airtight casings enclosed by a layer of woven fishnet fabric that prevented ballooning when the suit was pressurized. A layer … Read more

Experience showed that overheating was a problem in the Gemini space suits. The Apollo space suits had a layer of fabric made of tubing through which cool liquid flowed. A layer of linen provided some comfort, and the use of rubber, nylon, and aluminum ensured protection. Life support had to be mobile, so a backpack … Read more

The first attempt by the USSR to crash-land a satellite on the Moon, in 1959, came close to succeeding. No one as yet had the technology for a safe, soft landing. The satellite, Lunik I, also known as Mechta or Luna, flew by the Moon at a distance of only 3,300 miles (5,280 km). Lunik … Read more

After ten Apollo test missions, both manned and unmanned, Apollo 11 was launched on July 16, 1969. The astronauts on board were Commander Neil Armstrong, Lunar Module Pilot Edwin “Buzz” Aldrin, and Command Module Pilot Michael Collins. On July 20, 1969, Armstrong and Aldrin landed the lunar module Eagle on the Moon’s surface in the … Read more

There were three astronauts who could claim to be the first to orbit the Moon. On December 24, 1968, Frank Borman, William Anders, and James Lovell went into lunar orbit for 20 hours aboard Apollo 8. After their successful mission, the next step of the space program would be the one actually taken on the … Read more

The 1960s saw a great debate among scientists and the U.S. government as to what kind of vehicle would work best for all three stages of the Apollo mission. The mission required a launch, a visit to the Moon, and a return to Earth. In the end, NASA decided to launch one spacecraft to orbit … Read more

The Apollo lunar module had two main functions, to land safely on the Moon and take off again. The module was shaped something like a four-legged, octagonal spider, and was also known as the Lunar Excursion Module, or LEM. With legs fully extended in landing position, it stood about 23 feet (7 m) tall and … Read more

The Apollo spacecraft that sent American astronauts to the moon had two modules, the command module and the service module. The command module, where the three astronauts spent their time, measured 10 feet (3 m) x 12.5 feet (3.8 m). It had five windows and contained three couches for the astronauts; storage facilities; navigation, instrument, … Read more

Saturn rockets, based on missiles developed by the U.S. Department of Defense, launched most of the Apollo missions. The Saturn rocket boosters were developed by a team of German rocket scientists led by Wernher von Braun to launch heavy payloads into space. They were originally meant as a military satellite launcher, but they were adopted … Read more

On March 18, 1965, Alexei Leonov stepped out into space from his Vokshod 2 spacecraft, while his comrade Pavel Belyayev commanded the flight. Leonov wore a space suit and was connected to Vokshod 2 by a tether and radio communication. His space walk was successful, but Leonov’s space suit had expanded, and he was forced … Read more

The United States began its Pioneer program in 1958 under the auspices of the Department of Defense. Its purpose was to send a satellite into orbit around the Moon, but it never made it. NASA took over the program with the second attempted launch, on October 11, 1958, but had no better success. The closest … Read more

During the final 13 minutes before it crashed into the Moon, Ranger 7 sent back 4,316 photographs of the lunar surface. In 1965, two more Ranger satellites took pictures of the Moon before crashing, providing a total of more than 17,000 photographs. In February 1966, the USSR’s Luna 9 didn’t crash, but landed safely on … Read more

No one had ever landed on the Moon, and in 1961, when NASA’s Surveyor program began, some thought no one could. Controlling a safe landing on the Moon was critical to sending anyone up there. Surveyor 1 was launched on May 30, 1966, and became the first U.S. spacecraft to make a controlled landing on … Read more

Surveyor 7, launched on January 6, 1968, was the fifth and final spacecraft of in NASA’s Surveyor program to achieve a lunar soft landing. The spacecraft carried out equipments to test the Moon’s soil. Surveyor 7 scooped up lunar dust and rocks, and performed more than fifteen experiments on the soil, including tests to determine … Read more

John Glenn wasn’t the first person in space. The honor went to Soviet cosmonaut Yuri Gagarin, on April 21, 1961, almost a year before Glenn orbited the earth. The USSR reported a completely successful 1-hour and 48-minute orbit of the manned capsule Vostok 1. Later it was learned that trouble upon reentry caused the capsule’s … Read more

The USSR continued to use its Vostok capsule to send cosmonauts into orbit for increasingly long periods of time. Early in the 1960s, no one knew for sure whether people could survive space travel without serious side effects. Testing the limits of human endurance in space was an important process. Launched on August 6, 1961, … Read more

Project Gemini was NASA’s second human spaceflight program, and consisted of 10 manned flights between 1965 and 1966. The American Gemini spacecraft were the first to carry two people into space. NASA used the Gemini program to develop techniques for advanced space travel, and to prepare for the Apollo missions, whose objective was to land … Read more

NASA’s Gemini 3, carrying Virgil Grissom and John Young, was launched on March 23, 1965. It was the first manned Gemini flight, the seventh American flight into space, and the 17th manned spaceflight from Earth of all time. The test flight gave the astronauts a chance to try out maneuvers necessary to get to and … Read more

On July, 28, 1973, two spiders Arabella and Anita, were launched toward Skylab and fame. Their mission was to spin webs in outer space. They boarded Skylab 3 with three NASA astronauts. Arabella was put to work immediately. The spiders produced rather sloppy webs at first, but they adapted quickly. It took her about 2 … Read more

The USSR felt that they were lagging behind in the space race since the United States had sent two men, not just one, into space aboard Gemini 3. They converted the Vostok capsule, which had been designed for one cosmonaut, an astronaut in the Soviet, now Russian, space program, into a very cramped three-person spacecraft. … Read more

Sixty-five Explorer satellites, all unmanned, were launched from Earth between 1958 and 1984, seven failed to launch successfully. They were all sent into space to collect data and conduct experiments on specific phenomena. The areas of study included radiation belts, magnetic fields, solar wind, electromagnetic rays, the ionosphere, and Halley’s comet. In the aftermath of … Read more

After the Soviet space program’s launch of the world’s first artificial satellite on October 4, 1957, the U.S. Congress, alarmed by the threat to national security and technological leadership, urged immediate and swift action. In 1958, President Dwight D. Eisenhower established the National Aeronautics and Space Administration, or NASA for short, to run the country’s … Read more

On September 13, 1961, a Mercury capsule was launched into orbit and, after one complete revolution, landed safely. On board was a simulation of an astronaut. Afterwards, a Mercury capsule successfully carried the chimpanzee Enos twice around Earth. Despite the astronauts’ test pilot experience NASA first intended for them to be “minor participants” during their … Read more

Project Mercury was the first human spaceflight program of the United States and ran from 1959 through 1963 at a cost of $384 million dollars. Four of the Project Mercury spaceflights included monkeys, or non-human primates. Sam, a Rhesus macaque, was launched on 4 December 1959 on Little Joe 2 to 85 km altitude. Miss … Read more

Astronaut John Glenn Jr. was the first American to orbit the Earth. After numerous delays, his Mercury capsule, named Friendship 7, took off on February 20, 1962, and kept him in orbit for 5 hours. During reentry, NASA suspected that the capsule’s heat shield, protection against the deadly heat of friction caused by falling through … Read more

In 1926, Robert Goddard, a rocket engineer, fired the first rocket propelled by liquid fuel, solid fuel had already been discounted as not powerful enough to send anything into space. The first flight of a vehicle powered by a liquid-rocket took place on March 16, 1926 at Auburn, Massachusetts. Goddard’s rocket reached a velocity of … Read more

Rockets launch spacecraft into space. Without a good rocket, a satellite or space capsule isn’t going anywhere. The basic workings of a rocket begin with a store of liquid fuel and one of liquid oxygen. The two liquids are funneled into a combustion chamber where they interact, causing the fuel to burn. The gas produced … Read more

On October 4, 1957, Sputnik 1 was launched in the former Soviet Union, in Kazakhstan, near the town of Leninsk. This represented the first successful space launch. Sputnik 1 was little more than a radio transmitter, but its 90-minute orbit of the Earth ushered in the space age. Apart from being a technological first, Sputnik … Read more

In short, the space race was, and for some still is, a contest of power between Russia, formerly the Soviet Union (USSR), and the United States. It began with the USSR launching Sputnik 1. The march of history has limited, if not eliminated, the idea of a race, but it played a great part in … Read more

The USSR launched two more Sputniks, one in 1957 and one in 1958. Sputnik 2 carried a dog, named Laika, into orbit. She was the first living creature to travel in space. Laika did not seem to suffer from the launch, or from the weightlessness in orbit. The USSR, however, had not created a method … Read more

The Soviet launch of Sputnik spurred the United States to get its first satellite, Explorer 1, into orbit. The National Advisory Committee on Aeronautics (NACA), the predecessor of the National Aeronautics and Space Administration (NASA), adopted a U.S. Navy plan called Vanguard to launch the country’s first satellite. However, the satellite’s test run, in December … Read more

The planet Pluto’s perihelion, or closest point to the sun is 4.4 billion miles (7 billion km) from the Sun. Its aphelion, or farthest point is 7.4 billion miles (11.8 billion km). This usually makes Pluto the farthest planet from the Sun, but not always. Pluto’s orbit crosses the path of Neptune’s orbit, and for … Read more

Since the tiny Pluto crosses the gas giant’s path, it is reasonable to think that the two would collide. Perhaps Pluto would get caught by the larger planet’s gravitational force and become a satellite. This doesn’t happen because Pluto’s orbital inclination, the angle of its orbital plane is 17°, while Neptune’s is 1.8°. The two … Read more

Pluto is very dense, so astronomers believe it is mostly rock, unlike its neighboring gas giants. It seems to be covered with ice, perhaps composed of methane and nitrogen. Bright and dark areas appear on the surface, and Pluto has polar ice caps. Most astronomers expect that Pluto’s internal structure is differentiated, with the rocky … Read more

In 1988, when Pluto occulted, or passed in front of a star, astronomers were able to detect an atmosphere. If there were no atmosphere, the star would have blinked out like a light as soon as it was behind the planet’s surface. But first, the star’s light dimmed, as if passing behind a film. That … Read more

The planet Pluto has three known natural satellites, Charon, Nix and Hydra. Charon was first discovered by astronomer James Christy in 1978. We know little about Pluto, and we know less about its only moon, Charon. Pluto’s moon is about one-half the size of its host planet: 739 miles (1,182 km) in diameter. It orbits … Read more

Why Pluto is so different is not well understood, but it is obviously a unique planet. It is the farthest planet from the Sun, the smallest planet, and resembles the terrestrial planets more than its Jovian neighbors. Pluto has a peculiar orbit. It crosses Neptune’s orbital path so that at certain times Neptune is actually … Read more

Many astronomers believe that Pluto was an escaped moon of Neptune, knocked out of orbit by its largest current moon, Triton. This hypothesis has been heavily criticised because Pluto never comes near Neptune in its orbit. The discovery of Pluto made headlines across the globe, and its name was proposed by Venetia Burney, an eleven-year-old … Read more

Pluto is the smallest planet in the solar system. The dwarf planet has a diameter of 1,425 miles (2,280 km), which is less than half the width of the United States. It is about 50 percent of the size of Mercury, and 66 percent the size of Earth’s moon. Pluto’s moon, Charon, has a diameter … Read more

When astronomer William Herschel identified Uranus in 1781, astronomers determined that there must be at least one more planet beyond it to cause the idiosyncracies of its orbit. This led to the discovery of the planet Neptune in 1846. But even Neptune’s existence did not justify the peculiarities of Uranus’s orbit. Another planet had to … Read more

When Uranus was discovered in 1781, astronomers concluded that yet another, more distant, planet had to exist. Something, they figured, was exerting a strong gravitational influence on Uranus’s orbit. They called that something Planet X. The search for Planet X led to the identification of Neptune, but Neptune was not strong enough alone to so … Read more

Some astronomers have questioned whether Pluto should be classified as a planet, rather than an errant moon or an asteroid. The does not generate light; it is less massive than a star; it wanders through constellations; and it orbits the Sun, just like the other planets. Pluto’s orbit, however, is decidedly peculiar. Pluto’s distance from … Read more

Neptune’s Great Dark Spot, like Jupiter’s Great Red Spot and Saturn’s Great White Spot, indicates an atmospheric storm. It is an anticyclone, a cyclone rotating in a counterclockwise direction, about the size of Earth that travels eastward about 8° south of the equator at a pace of 100 feet (30 m) per second. The Great … Read more

Neptune’s internal structure is very similar to that of the planet Uranus. Neptune and Uranus are often considered a sub-class of gas giant termed “ice giants”, due to their smaller size and higher concentrations of volatiles relative to the gas giants Jupiter and Saturn. The planet Neptune has a partly rocky, but mostly icy, core … Read more

The weather on the planet Neptune is characterized by extremely dynamic storm systems. The winds around Neptune’s equator blow at a rate of almost 1,500 feet (450 m) per second, or just over 1,000 miles (1,600 km) per hour, making the smallest gas giant also one of the windiest. The equatorial winds blow in the … Read more

Neptune is over 1 billion miles (1.6 billion km) farther away from the Sun than Uranus, but the two planets are close in temperature: –365°F (-220°C) on Neptune; –355°F (-214°C) on Uranus. This results from Neptune’s interior, which is not as solid as Uranus’s. A partially fluid core will experience more movement than a solid … Read more

Neptune has at least five discernible rings made of microscopic particles of dust. They are so thin, diffuse, and uneven that all but one disappear at some point. The system begins about 10,000 miles (16,000 km) above Neptune’s clouds and extends for 13,000 miles (21,000 km). The widest ring, called the Plateau, stretches for almost … Read more