The Outer Solar System and Space Exploration – Flashcards

there are four giant planets made almost entirely of gases and ice. They have no solid surfaces on which we could land a space ship because they are essentially giant spheres of swirling gas. But they do have thick atmospheres, many moons, and all of them have rings. Together they make up about 99 percent of the mass that orbits the Sun. The major planets of the outer solar system are Jupiter, Saturn, Uranus, and Neptune

is the largest planet in the solar system and is at least 300 times more massive than Earth. Jupiter is made mostly of gaseous hydrogen and helium. Its most famous feature is the Great Red Spot, which can be seen from telescopes on Earth. Notice how Jupiter has bands of swirling clouds and how the Great Red Spot is also in motion. It is an extremely powerful storm that has been brewing on Jupiter for at least 275 years, maybe longer. Jupiter has more natural satellites, or moons, than any other planet in the solar system. The four largest moons, shown here, are collectively called the Galilean moons

Saturn is the sixth planet from the Sun and second largest in the solar system. It is made of hydrogen and helium gases and is most well known for its prominent rings. All of the gas giant planets actually have rings, but only Saturn's are easily discerned. The rings are mostly composed of countless particles of ice that orbit the planet. Saturn has 62 known moons, the largest of which is Titan.

the seventh planet from the Sun. Like Neptune beyond it, Uranus is made mostly of ice, including ices of water, methane, and ammonia gas. Uranus is the only planet to orbit the Sun on its side. It has a ring system, and 27 moons. In this picture, solid lines represent rings and dashed lines represent the orbits of some of those moons. The rings of Uranus are not made of ice, like Saturn's rings. They are made of extremely dark material, the composition of which is not yet known. In this picture you see six of Uranus' moons, the largest of which is named Titania, shown here as the second from the right.

eighth planet from the Sun. Neptune, like Uranus, is covered with ice. Its blue appearance comes from traces of methane in its atmosphere. Neptune has an active weather system and the strongest winds of any planet in the solar system. It has two massive storms known as the Great Dark Spot and the Small Dark Spot. Neptune has 13 known moons, the largest of which is Triton. We know very little about the northern polar end of Triton, but its southern polar cap is made of frozen nitrogen and methane and is seen in this picture. Triton also has geysers that spew out liquid nitrogen.

It includes many small objects that orbit the Sun, which are not categorized as planets. One of these is Pluto, which actually was listed as the ninth planet until 2006. Among the transNeptunian objects, Pluto, Haumea, Makemake, and Eris are now formally classified as dwarf planets. They, and several other objects of the Trans-neptunian region, are shown here. Notice the elongated shape of Haumea-it is believed to be a result of a giant collision with some other object in space. Many trans-neptunian objects have multiple satellites. Pluto, for example, has three satellites-Charon, Nix, and Hydra

several moons and rings

jupiter

ice

massive storm

Neptune

Mars

dwarf planets

*Ganymeade; Jupiter

-simply satisfying our curiosity about what is out there -finding out about the laws of the universe -protecting our country from the military power of other countries -gaining new knowledge

The German V-2 Rocket, like the one you see here, was the first man-made object in space. Germany mostly used them to demonstrate military power, and sent off hundreds of them in the 1940s, during World War II. After the war, the U.S. took possession of many of the V-2 rockets and began studying them for both military and scientific uses. The results of the studies of the V-2 rockets paved the way for U.S. space exploration. In 1947, the U.S. sent fruit flies into space aboard a V-2 rocket, and later corn seeds, in order to test survivability before sending humans into space.

The early V-2 Rockets could only go about 100 kilometers up and were not able to orbit Earth; thus their use was limited. In October 1957, the Soviets were the first to get an object to orbit Earth. This was the Sputnik satellite, and you see an artist's depiction of it here. This marked what many call the dawn of the Space Age. It was able to go much higher than the old V- 2 rockets and it stayed in orbit for several months. As it was above Earth, it sent out radio signals to try to understand the temperature and density of space. Sputnik's success led the U.S. to rush to begin its own space exploration program

This dog, named Laika, was the first dog in space. She was sent into orbit aboard a second Sputnik craft by the Soviets. Animals were sent into space before humans so we could see if living organisms could survive the launch into space and the conditions of weightlessness.

Moon exploration began in 1959 when the Russians landed the unmanned spacecraft, Luna 2, on the Moon. In the 1960s, U.S. President John Kennedy initiated a race to put a U.S. citizen on the surface of the Moon before the Soviets could get a Soviet citizen there. Under the Apollo Program, several U.S. missions were made to the Moon. On June 20, 1969, two U.S. astronauts, Buzz Aldrin and Neil Armstrong, became the first humans to contact the surface of the Moon. Their spacecraft, the Apollo 11, and other Apollo flights conducted experiments on the Moon and brought back rocks and data from the Moon. Five other Apollo missions also landed astronauts on the Moon, the last one in 1972. No humans have been on the Moon since then.

After the Apollo missions of the 1960s and early 1970s, the U.S. turned its space interests toward establishing a permanent space station—somewhere where astronauts could stay for long periods of time and conduct research over long time periods. In 1968, the U.S. began the U.S. Space Shuttle Program. This program was designed to create re-usable spacecraft that could carry crews into outer space and deliver satellites to space for exploratory trips. A key component of the space shuttle program was to develop several spacecraft that could be re-used, or sent back into space about 10 times each. Since 1968, space shuttles have launched into space and sent several crews to space stations where space station research is carried out. The shuttles also successfully set up satellites, which are used to protect us militarily and establish technologies to observe the universe and learn about its nature. Under U.S. law, the Space Shuttle program is set to expire in 2010. Its last mission will likely be in late 2010 or early 2011.

Since the Apollo missions of the 1960s and early 1970s, the U.S. has sent several satellites and other spacecraft into space. While none involved a human physically contacting another planet or other object, we have landed spacecraft on other planets and the moons of other planets. Using robotic spacecraft, we have collected soil samples from Venus and Mars in efforts to understand conditions on those planets. We have also conducted numerous "flyby" missions, in which spacecraft are sent to photograph views of the universe that we could not otherwise see. Here you see a photo of Jupiter's moon, Io; it is an image captured by the flyby mission of the Galileo spacecraft.

Construction on the International Space Station began in 1998. It is an international research facility in low Earth orbit. Though not the first space station to be built, it is the largest and it is actually still under construction as of 2010. It is a satellite, about 350 kilometers above the surface of Earth, and it travels at a speed of about 27,700 kilometers per hour. The ISS has been continuously occupied since November 2000, employing astronauts from several countries, including the U.S., China, Russia, Japan, Canada, and several European countries. Being able to perform long-term studies is the main advantage of the space station. The crew conducts research in biology, physics, astronomy, and meteorology. One thing they particularly focus on is the effects of long-term exposure to space on the human body. Scientists are studying how the body's muscles and bones respond to long periods in space in order to see if very long spaceflights to other planets could be possible. Astronauts stay at the space station for about six months at a time.

One of the major goals of the early twenty-first century is to send a human to Mars. In April 2010, U.S. President Barack Obama said that he would like the U.S. to continue exploring the Moon, but feels that since we have already been there, we should focus more attention on exploring Mars. He hopes to have a human land on Mars by 2030. A trip to Mars would take about two years, and could have yet unknown impacts on the human body. Right now, we think a trip to Mars would make the human heart too weak to pump blood, due to the effects of weightlessness, so more research is needed on how to make the trip successful. Most of the spacecraft that have been designed for Mars exploration have failed before completing their missions, but new research to improve them and to help us reach our goal is being done everyday.

-New knowledge and technologies that come from space exploration can be used in other parts of life. For example, space exploration has led to new knowledge in robotics, advances in heating and cooling technologies, and better understanding of the universe. -Medical advantages, such as heart pacemakers and advances in blood pressure reading technology, came from knowledge gained as scientists studied the effects of space on the human body. -The technology involved in space exploration may give the U.S. military advantage over other countries. -Agreements between countries involved in the ISS may generate cooperation and goodwill between people of different nationalities. -Space exploration simply expands our awareness and satisfies our curiosity, which some argue is a human need. Some say that the Moon landings of the 1960s created a change in society that sparked the environmental movement, because humans began to understand that we all live on the same Earth

From medical imaging devices to video game joysticks, there are numerous technologies that we value and use everyday that were first developed as part of the space exploration program. Check out this page from NASA that explains how the space program affects our modern lifestyle.

On the other hand, there are risks associated with space exploration. People who oppose space exploration, or at least oppose the amount of money that we spend on space exploration each year, give the following as some of their reasons: Some argue that it is just too expensive or that it takes research money away from programs to fight disease or make life better for those suffering from illness, poverty, and natural disasters on Earth. It is dangerous. Space exploration has not been without tragedy. The U.S. has lost 14 astronauts to shuttle explosions in two separate disasters. In January 1986, the Challenger space shuttle exploded just a few seconds after launch. In February 2003, the Columbia space shuttle exploded just before landing on Earth. In both cases, all astronauts on board were killed.

On January 26, 1986, the Space Shuttle Challenger took off from the Kennedy Space Center just east of Orlando, Florida. Aboard the shuttle were six NASA crew members and one civilian teacher, Christa McAuliffe. McAuliffe was the first teacher invited aboard the shuttle as part of a new project, Teachers in Space. Tragically, 73 seconds into its flight, the Challenger shuttle broke apart. All seven crew members died. Because this was a special launch, one that included a civilian teacher, many people watched the tragedy unfold live on television. United States President Ronald Regan appointed a special commission to investigate the Challenger disaster. The investigation halted the shuttle program for 32 months. Engineers eventually determined that an O?ring seal in the right rocket booster failed during the liftoff of the Challenger space shuttle. As a result of the investigation into the causes of the Challenger disaster, NASA implemented nine recommendations regarding the safety of shuttle flights and communication and organization within NASA. The Challenger disaster has remained a focal discussion point for issues surrounding workplace safety and ethics.

Any object that orbits a planet is a satellite. Natural satellites are a planet's moons. Artificial satellites are spacecraft that humans send into a planet's orbit to observe and study that planet

. The main goals of the shuttle program was to build spacecraft that could be re-used and sent into space multiple times, to send satellites on exploratory missions, and to take astronauts to a permanent space station. The goals of the International Space Station are to research the effects on the human body of staying in space for long periods of time and to conduct research on astronomy and physics. Flyby missions use satellites to fly past celestial bodies and capture photographs or images of them so we can study areas of the solar system that we could not otherwise see. For example, we have been able to see the dark side of the Moon through flyby missions. From Earth we would never otherwise be able to see that side of the Moon.